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As filed with the Securities and Exchange Commission on April 5, 2023
Registration No. 333-     
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM S-4
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
ADAPTIMMUNE THERAPEUTICS PLC
(Exact name of registrant as specified in its charter)
England and Wales
2836
Not Applicable
(State or other jurisdiction of
incorporation or organization)
(Primary Standard Industrial
Classification Code Number)
(I.R.S. Employer
Identification No.)
60 Jubilee Avenue, Milton Park
Abingdon, Oxfordshire OX14 4RX
(44) 1235 430000
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)
Adrian Rawcliffe
Chief Executive Officer
Adaptimmune Therapeutics plc
60 Jubilee Avenue, Milton Park
Abingdon, Oxfordshire OX14 4RX
United Kingdom
(44) 1235 430000
(Name, address, including zip code, and telephone number, including area code, of agent for service)
Copies of communications to:
Jackie Cohen
Ropes & Gray LLP
1211 Avenue of the Americas
New York, NY 10036-8704
(212) 596-9000
David S. Bakst, Esq.
Mayer Brown LLP
1221 Avenue of the Americas
New York, New York 10020
Telephone: (212) 506-2500
Garry E. Menzel
President and Chief Executive
Officer
TCR2 Therapeutics Inc.
100 Binney Street, Suite 710
Cambridge, Massachusetts 02142
(617) 949-5200
Mitchell S. Bloom
Robert Masella
Andrew H. Goodman
Tevia K. Pollard
Goodwin Procter LLP
100 Northern Avenue
Boston, MA 02110
(617) 570-1055
Approximate date of commencement of the proposed sale of the securities to the public: As soon as practicable after the effective date of this Registration Statement and upon consummation of the transactions described herein.
If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. ☐
If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer”, “accelerated filer”, “non-accelerated filer”, “smaller reporting company”, and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):
Large accelerated filer
Accelerated Filer
Non-accelerated filer
Smaller reporting company
Emerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐
If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:
Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) ☐
Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) ☐
The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment that specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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The information in this joint proxy statement/prospectus is not complete and may be changed. We may not issue these securities until the registration statement filed with the Securities and Exchange Commission is effective. This joint proxy statement/prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state or jurisdiction where the offer or sale is not permitted.
PRELIMINARY JOINT PROXY STATEMENT/PROSPECTUS — SUBJECT TO COMPLETION — DATED APRIL 5, 2023
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MERGER PROPOSED — YOUR VOTE IS VERY IMPORTANT
Adaptimmune Therapeutics PLC
Registered office: 60 Jubilee Avenue, Milton Park
Abingdon, Oxfordshire OX14 4RX, U.K.
Incorporated in England & Wales with registered no. 09338148
[•], 2023
Dear Adaptimmune Therapeutics plc Shareholder:
This letter, the notice of the general meeting (the “Adaptimmune general meeting”) set out in this document (the “Notice”) and associated materials for the Adaptimmune general meeting are being sent or supplied to you because, as of [•], 2023, you are registered as a holder of ordinary shares in the register of members of Adaptimmune Therapeutics plc (“Adaptimmune”). However, this letter, the Notice and associated materials will also be available to holders of Adaptimmune American Depositary Shares (“Adaptimmune ADSs”) and contain information relevant to holders of Adaptimmune ADSs.
As previously announced, on March 5, 2023, Adaptimmune entered into an Agreement and Plan of Merger, as it may be amended from time to time (the “merger agreement”), with TCR2 Therapeutics Inc. (“TCR2”), and CM Merger Sub, Inc., a Delaware corporation (“Merger Sub”), pursuant to which Merger Sub will be merged with and into TCR2 (the “merger”), with TCR2 surviving the merger as a wholly-owned direct subsidiary of CM Intermediate Sub II, Inc., a Delaware corporation and wholly-owned subsidiary of Adaptimmune (“CM Intermediate”).
If the merger is completed, each issued and outstanding share of TCR2 common stock, par value $0.0001 per share (“TCR2 Common Stock”) (other than shares of TCR2 Common Stock held by TCR2 as treasury stock, or shares of TCR2 Common Stock owned by Adaptimmune, Merger Sub or any direct or indirect wholly-owned subsidiaries of Adaptimmune), including shares of TCR2 Common Stock underlying TCR2 restricted stock units that immediately vest upon a change of control of TCR2, will be converted into the right to receive 1.5117 (the “Exchange Ratio”) Adaptimmune ADSs.
In connection with the merger, each option to acquire shares of TCR2 Common Stock granted under a TCR2 equity plan or otherwise set forth in the merger agreement that is outstanding and unexercised, whether or not vested, will be assumed and substituted for an award of options to purchase a number of ordinary shares of Adaptimmune, par value £0.001 per share (the “Adaptimmune ordinary shares”) or Adaptimmune ADSs based on a calculation equal to the product of (i) the total number of shares of TCR2 Common Stock subject to such TCR2 option immediately prior to the effective time of the merger (the “Effective Time”) multiplied by (ii) six times the Exchange Ratio (the “Ordinary Share Exchange Ratio”), in the case of Adaptimmune ordinary shares or the Exchange Ratio, in the case of Adaptimmune ADSs, as applicable, with any fractional Adaptimmune ordinary shares or Adaptimmune ADSs rounded down to the nearest whole ordinary share or ADS, as applicable. Each award of restricted stock units with respect to shares of TCR2 Common Stock (“TCR2 restricted stock units”) granted under a TCR2 equity plan or otherwise set forth in the merger agreement (other than restricted stock units that immediately vest upon a change of control of TCR2) will be assumed and substituted for an award of a restricted stock unit-style option to purchase a number of Adaptimmune ordinary shares or Adaptimmune ADSs based on a calculation equal to the product of (i) the total number of shares of TCR2 Common Stock subject to such TCR2 restricted stock unit multiplied by (ii) the Ordinary Share Exchange Ratio or the Exchange Ratio, as applicable, with any fractional shares rounded down to the nearest whole Adaptimmune ordinary share or Adaptimmune ADS, as applicable.
Adaptimmune ADSs are listed on the Nasdaq Global Select Market (“Nasdaq”) under the symbol “ADAP.” Shares of TCR2 Common Stock are listed on Nasdaq under the symbol “TCRR.”
The merger is conditioned upon, among other things, the affirmative vote of a majority of the votes cast by shareholders of issued Adaptimmune ordinary shares in favor of (a) authorizing the Adaptimmune Board of Directors (the “Adaptimmune Board”) (or a duly authorized committee thereof) to allot all

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Adaptimmune ordinary shares to be issued in connection with the merger (to be represented by Adaptimmune ADSs) and (b) approving the issuance of Adaptimmune ordinary shares to be represented by Adaptimmune ADSs in connection with the merger at the Adaptimmune general meeting to be held on [•], 2023.
I am pleased to confirm that the Adaptimmune general meeting will take place at [] London time ([] Eastern Time) on [], 2023 at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX. The Notice is set out in this document and it contains the resolutions to be proposed at the Adaptimmune general meeting (the “Resolutions”).
Action to be taken by holders of Adaptimmune ordinary shares
If you are a holder of Adaptimmune ADSs, please ignore this section and refer instead to the section below — “Holders of Adaptimmune ADSs”.
If you are a holder of Adaptimmune ordinary shares and are planning to attend the Adaptimmune general meeting in person (or by way of corporate representative) it would be helpful if you could inform Morrow Sodali, Adaptimmune’s proxy solicitor, by calling toll-free at 1 (800) 662-5200. Banks, brokerage firms and other nominees may call collect at 1 (203) 658-9400.
If you are unable to attend the Adaptimmune general meeting, you can still vote on the Resolutions by appointing a proxy. A form of proxy for use at the Adaptimmune general meeting is enclosed or is being sent to you by email if you have opted to receive information by email. You are able to submit your proxy vote online at www.investorcentre.co.uk/eproxy (see instructions on form of proxy) to arrive by no later than [] London time ([] Eastern Time) on [], 2023.
Alternatively, if you have received a printed form of proxy and prefer to return it by post, you are advised to complete and return the form of proxy in accordance with the instructions printed on it and so as to arrive at Adaptimmune’s registrar, Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England as soon as possible but in any event by no later than [] London time ([] Eastern Time) on [], 2023. CREST members may appoint a proxy by using the CREST electronic proxy appointment service. The return of a form of proxy or the electronic appointment of a proxy does not preclude you from attending and voting at the Adaptimmune general meeting if you so wish.
In order to attend and vote at the Adaptimmune general meeting as a holder of Adaptimmune ordinary shares or for your form of proxy to remain valid, you must continue to be registered as a holder of Adaptimmune ordinary shares in Adaptimmune’s register of members as of [] London time ([] Eastern Time) on [], 2023.
Therefore, if you sell or transfer your Adaptimmune ordinary shares on or prior to [], 2023, your form of proxy can no longer be used and if submitted (whether before or after you sell or transfer your Adaptimmune ordinary shares) will be treated as invalid. Please pass this document to the person who arranged the sale or transfer for delivery to the purchaser or transferee. The purchaser or transferee should contact Morrow Sodali, Adaptimmune’s proxy solicitor, to request a new form of proxy for its use.
Should you elect to convert your holding of ordinary shares in the capital of Adaptimmune into an interest in the capital of Adaptimmune represented by ADSs before the Adaptimmune general meeting, you will cease to be a holder of Adaptimmune ordinary shares in your own name and will not be entitled to vote at the Adaptimmune general meeting as a holder of Adaptimmune ordinary shares. You will also not be able to use the form of proxy that has been sent to you. However, you may be able to exercise your vote as a holder of Adaptimmune ADSs representing Adaptimmune ordinary shares — please refer to the next section — “Holders of Adaptimmune ADSs”.
Holders of Adaptimmune ADSs
In order to exercise your vote as a holder of Adaptimmune ADSs, you or your bank, broker or nominee must be registered as a holder of Adaptimmune ADSs in the Adaptimmune ADS register by [] Eastern Time on [], 2023 (the record date for holders of Adaptimmune ADSs).
If you hold Adaptimmune ADSs through a bank, broker or nominee on [], 2023, the materials for holders of Adaptimmune ADSs, which include the notice of the Adaptimmune general meeting from Citibank, N.A. as depositary bank (the “depositary bank”), the Adaptimmune general meeting documentation, and the Adaptimmune ADS proxy card, will be sent to your bank, broker or nominee who should forward the materials to you. Please reach out to your bank, broker or nominee to provide your voting instructions.

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Please note that Adaptimmune ADS proxy cards submitted by holders of Adaptimmune ADSs must be received by the depositary bank by no later than [] Eastern Time on [], 2023.
Contact for Holders of Adaptimmune ADSs
If you have queries about how you can deliver voting instructions, please contact Citibank, N.A. —  ADR Shareholder Services at tel: +1-877-248-4237 (toll free within the United States) or +1-781-575-4555 (for international callers) or by email: citibank@shareholders-online.com or at Citibank Shareholder Services, P.O. Box 43099, Providence, RI 02940-5000.
Contact at Adaptimmune
If at any point you have any queries, please contact Morrow Sodali, Adaptimmune’s proxy solicitor, by calling toll free at 1 (800) 662-5200.
Your vote is very important, regardless of the number of shares of Adaptimmune ordinary shares or Adaptimmune ADSs you own. Whether or not you expect to attend the Adaptimmune general meeting in person, please vote or otherwise submit a proxy to vote your shares as promptly as possible so that your shares may be represented and voted at the Adaptimmune general meeting.
THE ADAPTIMMUNE BOARD HAS (I) UNANIMOUSLY DETERMINED THAT THE TERMS OF THE MERGER AND THE OTHER TRANSACTIONS CONTEMPLATED BY THE MERGER AGREEMENT ARE MOST LIKELY TO PROMOTE THE SUCCESS OF ADAPTIMMUNE FOR THE BENEFIT OF ADAPTIMMUNE SHAREHOLDERS AS A WHOLE; (II) UNANIMOUSLY APPROVED, ADOPTED AND DECLARED ADVISABLE THE MERGER AGREEMENT AND THE TRANSACTIONS CONTEMPLATED BY THE MERGER AGREEMENT, INCLUDING THE MERGER; (III) UNANIMOUSLY RESOLVED TO RECOMMEND THAT ADAPTIMMUNE SHAREHOLDERS APPROVE (A) AUTHORIZATION OF THE ADAPTIMMUNE BOARD TO ALLOT ALL ADAPTIMMUNE ORDINARY SHARES TO BE ISSUED IN CONNECTION WITH THE MERGER AND (B) ISSUANCE OF ADAPTIMMUNE ORDINARY SHARES (AND, ACCORDINGLY ADAPTIMMUNE ADSs); AND (IV) UNANIMOUSLY DETERMINED THAT SUCH PROPOSALS BE SUBMITTED TO ADAPTIMMUNE SHAREHOLDERS FOR APPROVAL AT A MEETING OF ADAPTIMMUNE SHAREHOLDERS DULY CALLED AND HELD FOR SUCH PURPOSES. THE ADAPTIMMUNE BOARD MADE ITS DETERMINATION AFTER CONSIDERING A NUMBER OF REASONS MORE FULLY DESCRIBED IN THIS JOINT PROXY STATEMENT/PROSPECTUS.
THE ADAPTIMMUNE BOARD RECOMMENDS THAT YOU VOTE “FOR” THE AUTHORIZATION OF THE ADAPTIMMUNE BOARD (OR A DULY AUTHORIZED COMMITTEE THEREOF) TO ALLOT ALL ADAPTIMMUNE ORDINARY SHARES TO BE ISSUED IN CONNECTION WITH THE MERGER (TO BE REPRESENTED BY ADAPTIMMUNE ADSs) AND “FOR” THE APPROVAL OF THE ISSUANCE OF ADAPTIMMUNE ORDINARY SHARES (AND ACCORDINGLY, ADAPTIMMUNE ADSs) TO BE ISSUED IN CONNECTION WITH THE MERGER.
For a discussion of risk factors that you should consider in evaluating the transaction, see the section of this joint proxy statement/prospectus titled, “Risk Factors” beginning on page 29 of this joint proxy statement/prospectus.
We urge you to read this joint proxy statement/prospectus carefully and in its entirety.
Sincerely,
David M. Mott
Chairman of the Board
Adaptimmune Therapeutics plc
Neither the Securities and Exchange Commission nor any state or provincial securities commission or regulatory authority has approved or disapproved of these securities or passed upon the adequacy or accuracy of this joint proxy statement/prospectus. Any representation to the contrary is a criminal offense.
This joint proxy statement/prospectus is dated [•], 2023 and is first being mailed to Adaptimmune shareholders on or about [•], 2023.

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Adaptimmune Therapeutics PLC
60 Jubilee Avenue, Milton Park
Abingdon, Oxfordshire X14 4RX,
United Kingdom
NOTICE OF GENERAL MEETING OF SHAREHOLDERS
TO BE HELD ON [], 2023
NOTICE is hereby given that a general meeting of shareholders of Adaptimmune Therapeutics plc (“Adaptimmune”), a public limited company incorporated under the laws of England and Wales, will be held at [•] London time ([•] Eastern Time) on [•], 2023, at Adaptimmune’s corporate headquarters, located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, (the “Adaptimmune general meeting”), for the following purposes:
Ordinary resolutions
1.
Allotment Proposal.   Without prejudice to all existing authorities (which will remain in full force and effect), to authorize Adaptimmune’s directors generally and unconditionally, for the purposes of section 551 of the U.K. Companies Act 2006 (the “Companies Act 2006”), to allot ordinary shares in Adaptimmune, and grant rights to subscribe for or to convert any security into ordinary shares in Adaptimmune, up to a maximum aggregate nominal amount of £[•] in connection with the transactions contemplated by the Agreement and Plan of Merger, dated as of March 5, 2023, as amended, by and among Adaptimmune, TCR2 Therapeutics Inc. (“TCR2”) and CM Merger Sub, Inc. (the “merger”) for a period expiring (unless previously renewed, varied or revoked by resolution of Adaptimmune) at the conclusion of Adaptimmune’s annual general meeting in 2024, provided that Adaptimmune may make offers or agreements before this authority expires which would or might require ordinary shares in Adaptimmune to be allotted, or rights to subscribe for or convert any security into ordinary shares in Adaptimmune to be granted, after this authority has expired and the directors of Adaptimmune may allot ordinary shares in Adaptimmune and grant rights in pursuance of those offers or agreements as if this authority had not expired (the “Allotment Proposal”); and
2.
Share Issuance Proposal.   Subject to and conditional upon the passing of the Allotment Proposal, to approve the issuance of ordinary shares of Adaptimmune, par value £0.001 per share (the “Adaptimmune ordinary shares”) to be represented by Adaptimmune American Depositary Shares (“Adaptimmune ADSs”) in connection with the merger for purposes of applicable Nasdaq rules (the “Share Issuance Proposal”).
Proposals 1 and 2 will be proposed as ordinary resolutions and under English law, assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution.
The results of any polls taken on the resolutions at the Adaptimmune general meeting and any other information required by the Companies Act 2006 will be made available on the Adaptimmune website (https://www.adaptimmune.com) as soon as reasonably practicable following the Adaptimmune general meeting and for the required period thereafter.
 

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BY ORDER OF THE BOARD Registered office
60 Jubilee Avenue, Milton Park,
Margaret Henry
Company Secretary
[•], 2023
Abingdon,
Oxfordshire OX14 4RX, United Kingdom
Registered in England and Wales
No 09338148
Notes
(a)
Only those members registered in the register of members of Adaptimmune at [•] London time ([•] Eastern Time) on [•], 2023 will be entitled to attend and vote at the Adaptimmune general meeting in respect of the number of ordinary shares registered in their name at the time. Changes to entries on the relevant register after that deadline will be disregarded in determining the rights of any person to attend and vote at the Adaptimmune general meeting. Should the Adaptimmune general meeting be adjourned to a time not more than 48 hours after the deadline, the same deadline will also apply for the purpose of determining the entitlement of members to attend and vote (and for the purpose of determining the number of votes they may cast) at the adjourned Adaptimmune general meeting. Should the Adaptimmune general meeting be adjourned for a longer period, then to be so entitled, members must be entered on the register at the time which is 48 hours before the time fixed for the adjourned Adaptimmune general meeting or, if Adaptimmune gives notice of the adjourned Adaptimmune general meeting, at the time specified in the notice.
(b)
Any member may appoint a proxy to attend, speak and vote on his/her behalf. A member may appoint more than one proxy in relation to the Adaptimmune general meeting provided that each proxy is appointed to exercise the rights attached to a different share or shares of the member. A proxy need not be a member but must attend the meeting in person. Proxy forms should be lodged with Adaptimmune’s Registrar (Computershare) not later than [•] London time ([•] Eastern Time) on [•], 2023. Completion and return of the appropriate proxy form does not prevent a member from attending and voting in person if he/she is entitled to do so and so wishes. The attached joint proxy statement/prospectus explains proxy voting and the matters to be voted on in more detail. Please read the joint proxy statement/prospectus carefully. For specific information regarding the voting of your Adaptimmune ordinary shares, please refer to this joint proxy statement/prospectus under the section entitled “Questions and Answers About the Merger”.
(c)
Any corporation which is a member can appoint one or more corporate representatives who may exercise on its behalf all of its powers as a member provided that they do not do so in relation to the same shares.
(d)
In the case of joint holders, the vote of the senior who tenders the vote whether in person or by proxy will be accepted to the exclusion of the votes of any other joint holders. For these purposes, seniority shall be determined by the order in which the names stand in the Adaptimmune’s relevant register or members for the certificated or uncertificated shares of Adaptimmune (as the case may be) in respect of the joint holding.
(e)
CREST members who wish to appoint a proxy or proxies through the CREST electronic proxy appointment service may do so for the Adaptimmune general meeting and any adjournments of it by using the procedures described in the CREST Manual. CREST personal members or other CREST sponsored members, and those CREST members who have appointed voting service providers, should refer to their sponsors or voting service providers, who will be able to take the appropriate action on their behalf.
For a proxy appointment or instruction made using the CREST service to be valid, the appropriate CREST message (a “CREST Proxy Instruction”) must be properly authenticated in accordance with Euroclear’s specifications and must contain the information required for those instructions as described in the CREST Manual (available via www.euroclear.com). The message, regardless of whether it relates to the appointment of a proxy or to an amendment to the instruction given to the previously appointed proxy, must, to be valid, be transmitted so as to be received by Adaptimmune’s agent 3RA50 by [•] London time ([•] Eastern Time) on [•], 2023. For this purpose, the time of receipt will be taken to be the time (as determined by the timestamp applied to the message by the CREST Applications Host)
 

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from which Adaptimmune’s agent is able to retrieve the message by enquiry to CREST in the manner prescribed by CREST. After this time, any change of instructions to proxies appointed through CREST should be communicated to the appointee through other means.
CREST members and, where applicable, their CREST sponsors or voting service providers should note that Euroclear UK does not make available special procedures in CREST for any particular messages. Normal system timings and limitations will, therefore, apply in relation to the input of CREST Proxy Instructions. It is the responsibility of the CREST member concerned to take (or, if the CREST member is a CREST personal member or sponsored member or has appointed voting service providers, to procure that its CREST sponsors or voting service providers take) such action as shall be necessary to ensure that a message is transmitted by means of the CREST system by any particular time. In this connection, CREST members and, where applicable, their CREST sponsors or voting service providers are referred, in particular, to those sections of the CREST Manual concerning practical limitations of the CREST system and timings.
Adaptimmune may treat as invalid a CREST Proxy Instruction in the circumstances set out in Regulation 35(5)(a) of the Uncertificated Securities Regulations 2001.
(f)
As of [•], 2023 (being the last practicable date before circulation of this Notice), Adaptimmune’s issued ordinary share capital consisted of [•] Adaptimmune ordinary shares, carrying one vote each. Therefore, the total voting rights in Adaptimmune as of that date are [•].
(g)
Except as set out in the notes to this Notice, any communication with Adaptimmune in relation to the Adaptimmune general meeting, including in relation to proxies, should be sent to Adaptimmune’s Registrar, Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England. No other means of communication will be accepted. In particular, you may not use any electronic address provided either in this notice or in any related documents to communicate with Adaptimmune for any purpose other than those expressly stated.
 

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MERGER PROPOSED — YOUR VOTE IS VERY IMPORTANT
[•], 2023
To the Stockholders of TCR2 Therapeutics Inc.:
On March 5, 2023, TCR2 Therapeutics Inc. (“TCR2”), Adaptimmune Therapeutics plc (“Adaptimmune”) and CM Merger Sub, Inc., an indirect wholly-owned subsidiary of Adaptimmune (“Merger Sub”), entered into an Agreement and Plan of Merger (which, as it may be amended from time to time, the “merger agreement”) that provides for the merger described below. On the terms and subject to the conditions set forth in the merger agreement, Merger Sub will merge with and into TCR2 (the “merger”) with TCR2 surviving as an indirect wholly-owned subsidiary of Adaptimmune.
Upon completion of the merger, each share of common stock, par value $0.0001 per share, of TCR2 (the “TCR2 Common Stock”) issued and outstanding (other than certain excluded shares as described in the merger agreement), including shares of TCR2 Common Stock underlying TCR2 restricted stock units that vest upon a change of control, that you own will be converted into the right to receive 1.5117 (the “Exchange Ratio”) Adaptimmune American Depositary Shares (“Adaptimmune ADSs”) (which we collectively refer to as the “merger consideration”).
The Exchange Ratio is fixed and will not be adjusted to reflect changes in the price of shares of TCR2 Common Stock or Adaptimmune ADSs prior to the completion of the merger. The Adaptimmune ADSs, each of which represents the right to receive six ordinary shares of Adaptimmune, par value £0.001 per share (the “Adaptimmune ordinary shares”), issued in connection with the merger will be listed on the NASDAQ Global Select Market (“Nasdaq”). Based on the number of Adaptimmune and TCR2 securities outstanding on [•], 2023, using the treasury stock method, upon completion of the merger, we expect that former TCR2 securityholders would receive approximately 25% of the equity of the combined company. Adaptimmune ADSs are traded on Nasdaq under the symbol “ADAP”. Shares of TCR2 Common Stock are traded on Nasdaq under the symbol “TCRR”. We encourage you to obtain current quotes for Adaptimmune ADSs and shares of TCR2 Common Stock. This joint proxy statement/prospectus presents information on the basis of Adaptimmune ADSs, which are the securities issuable in connection with the merger.
Because the Exchange Ratio is fixed, the market value of the merger consideration to TCR2’s stockholders (the “TCR2 stockholders”) will fluctuate with the market price of the Adaptimmune ADSs and will not be known at the time that TCR2 stockholders vote on the merger. Based on the reference price of Adaptimmune ADSs of $1.76 on Nasdaq on March 3, 2023, the last full trading day before the public announcement of the merger agreement, the implied value of the merger consideration to TCR2 stockholders was approximately $2.66 per share of TCR2 Common Stock. The price quoted on Nasdaq for Adaptimmune ADSs to which Adaptimmune and TCR2 referred when fixing the Exchange Ratio is referred to in this joint proxy statement/prospectus as the “reference price.” On March 28, 2023, the closing price of Adaptimmune ADSs on Nasdaq was $1.06 per share, resulting in an implied value of the merger consideration to TCR2 stockholders of $1.60 per share of TCR2 Common Stock.
At the special meeting of TCR2 stockholders (the “TCR2 special meeting”), TCR2 stockholders will be asked to consider and vote on (1) a proposal to adopt the merger agreement (the “merger proposal”) and (2) a proposal to approve the adjournment or postponement of the TCR2 special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes at the time of the TCR2 special meeting to approve the merger proposal or to ensure that any supplement or amendment to this joint proxy statement/prospectus is timely provided to TCR2 stockholders. The board of directors of TCR2 recommends that TCR2 stockholders vote “FOR” each of the proposals to be considered at the TCR2 special meeting.
 

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We cannot complete the merger unless the merger proposal is approved by TCR2 stockholders. Your vote on these matters is very important, regardless of the number of shares you own. Whether or not you plan to attend the TCR2 special meeting, please promptly mark, sign and date the accompanying proxy card and return it in the enclosed postage-paid envelope or call the toll-free telephone number or use the Internet as described in the instructions included with your proxy card in order to authorize the individuals named on your proxy card to vote your shares at the TCR2 special meeting.
This joint proxy statement/prospectus provides you with important information about the TCR2 special meeting, the merger, and each of the proposals. We encourage you to read the entire document carefully, in particular the “Risk Factors” section beginning on page 29 of this joint proxy statement/prospectus for a discussion of risks relevant to the merger.
We look forward to the successful completion of the merger.
Sincerely,
                  
Garry E. Menzel
President and Chief Executive Officer
TCR2 Therapeutics Inc.
 

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100 Binney Street, Suite 710
Cambridge, Massachusetts 02142
NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON [], 2023
To the Stockholders of TCR2 Therapeutics Inc.:
Notice is hereby given that TCR2 Therapeutics Inc. (“TCR2”) will hold a special meeting of its stockholders (the “TCR2 special meeting”) virtually via the Internet on [•], 2023, beginning at [•], Eastern Time.
The TCR2 special meeting will be held in a virtual meeting format only, via live webcast, and there will not be a physical meeting location. You will be able to attend the TCR2 special meeting online and to vote your shares electronically at the meeting by visiting www.proxydocs.com/TCRR to register and entering your control number included on your proxy card or on the instructions that accompanied your proxy materials (the “special meeting website”).
The TCR2 special meeting will be held for the following purposes:

to consider and vote on a proposal to adopt the Agreement and Plan of Merger, dated as of March 5, 2023 (as it may be amended from time to time, the “merger agreement”) by and among TCR2, Adaptimmune Therapeutics plc (“Adaptimmune”) and CM Merger Sub, Inc., an indirect wholly-owned subsidiary of Adaptimmune (“Merger Sub”), pursuant to which Merger Sub will merge with and into TCR2 (the “merger”), with TCR2 surviving the merger as a wholly-owned direct subsidiary of CM Intermediate Sub II, Inc., a Delaware corporation and subsidiary of Adaptimmune (the “merger proposal”); and

to consider and vote on a proposal to approve the adjournment or postponement of the TCR2 special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes at the time of the TCR2 special meeting to approve the merger proposal or to ensure that any supplement or amendment to this joint proxy statement/prospectus is timely provided to TCR2 stockholders (the “TCR2 adjournment proposal”).
TCR2 will transact no other business at the TCR2 special meeting. The accompanying joint proxy statement/prospectus, including the merger agreement, as amended, attached thereto as Annex A, contains further information with respect to these matters.
Stockholders of record at the close of business on [•], 2023 (which we refer to as the “TCR2 Record Date”) will be entitled to notice of and to vote at the TCR2 special meeting or any adjournment or postponement of the TCR2 special meeting.
The TCR2 board of directors (the “TCR2 Board”) has (i) unanimously determined that the merger agreement and the other transactions contemplated thereby are advisable, fair to and in the best interests of TCR2 and its stockholders, (ii) unanimously approved, adopted and declared advisable the merger agreement and the transactions contemplated thereby, (iii) unanimously resolved, subject to Section 5.3(c) of the merger agreement, to recommended that the TCR2 stockholders adopt the merger agreement and the transactions contemplated thereby, and (iv) directed that the merger agreement and the transactions contemplated thereby be submitted to the TCR2 stockholders for adoption. The TCR2 Board recommends that TCR2 stockholders vote “FOR” the merger proposal and “FOR” the TCR2 adjournment proposal.
Your vote is very important, regardless of the number of shares of TCR2 Common Stock you own. The parties cannot complete the transactions contemplated by the merger agreement, including the merger,
 

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without approval of the merger proposal. Assuming a quorum is present, the approval of the merger proposal requires the affirmative vote of a majority of the outstanding shares of TCR2 Common Stock entitled to vote on the merger proposal.
Whether or not you plan to attend the TCR2 special meeting via the special meeting website, TCR2 urges you to please promptly mark, sign and date the accompanying proxy and return it in the enclosed postage-paid envelope, which requires no postage if mailed in the United States, or to submit your votes electronically by calling the toll-free telephone number or using the Internet as described in the instructions included with the accompanying proxy card, so that your shares may be represented and voted at the TCR2 special meeting. If you hold your shares through a broker, bank or other nominee in “street name” (instead of as a registered holder), please follow the instructions on the voting instruction form provided by your bank, broker or nominee to vote your shares. The list of TCR2 stockholders entitled to vote at the TCR2 special meeting will be available at TCR2’s headquarters for examination by any stockholder for any purpose germane to the meeting for a period of at least 10 days prior to the TCR2 special meeting. If you would like to examine the list of TCR2 stockholders of record, please contact TCR2’s Corporate Secretary by emailing corporatesecretary@tcr2.com, or by a written request addressed to TCR2 Therapeutics Inc., 100 Binney Street, Suite 710, Cambridge, Massachusetts 02142, Attention: Corporate Secretary or by calling 1-617-949-5200 to schedule an appointment or request access. The list of TCR2 stockholders will be made available for examination electronically upon request to TCR2’s Corporate Secretary, subject to TCR2’s satisfactory verification of stockholder status. The list of TCR2 stockholders entitled to vote at the TCR2 special meeting will also be available for examination by any TCR2 stockholder during the TCR2 special meeting via the special meeting website at www.proxydocs.com/TCRR.
If you have any questions about the merger, please contact TCR2 as indicated above.
If you have any questions about how to vote or direct a vote in respect of your shares of TCR2 Common Stock, you may contact TCR2’s proxy solicitor, Innisfree M&A Incorporated, toll-free at 1 (877) 750-8233. Banks and brokers may call collect at 1 (212) 750-5833.
By Order of the Board of Directors,
Garry E. Menzel
President and Chief Executive Officer
TCR2 Therapeutics Inc.
100 Binney Street
Suite 710
Cambridge, Massachusetts 02142
Dated: [•]
 

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ABOUT THIS JOINT PROXY STATEMENT/PROSPECTUS
This joint proxy statement/prospectus, which forms part of a registration statement on Form S-4, which constitutes a prospectus of Adaptimmune Therapeutics plc (“Adaptimmune”), under Section 5 of the Securities Act of 1933, as amended (the “Securities Act”), with respect to the Adaptimmune ordinary shares, par value £0.001 per share (the “Adaptimmune ordinary shares”), certain of which are represented by Adaptimmune ADSs, and the Adaptimmune American Depositary Shares (“Adaptimmune ADSs”) to be delivered pursuant to the Agreement and Plan of Merger, dated as of March 5, 2023, by and among Adaptimmune, TCR2 Therapeutics Inc. (“TCR2”) and CM Merger Sub, Inc. (“Merger Sub”), as amended by Amendment No. 1 to the Agreement and Plan of Merger, dated as of April 5, 2023, as it may be further amended from time to time (the “merger agreement”), pursuant to which Merger Sub will be merged with and into TCR2 (the “merger”), with TCR2 surviving the merger as a wholly-owned indirect subsidiary of Adaptimmune.
This document also constitutes a proxy statement under Section 14(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), of each of Adaptimmune and TCR2. This joint proxy statement/prospectus also constitutes a notice of meeting with respect to each of the general meeting of Adaptimmune shareholders (the “Adaptimmune general meeting”), at which Adaptimmune shareholders will be asked to consider and vote on (i) a proposal to authorize the Adaptimmune Board of Directors (“Adaptimmune Board”) (or a duly authorized committee thereof) to allot new shares or to grant rights to subscribe for or to convert any security into Adaptimmune ordinary shares up to a maximum aggregate nominal amount of £[•] in connection with the merger (the “Allotment Proposal”) and (ii) a proposal to approve the issuance of shares of Adaptimmune ordinary shares to be represented by Adaptimmune ADSs in connection with the merger for purposes of applicable Nasdaq Global Select Market (“Nasdaq”) rules (the “Share Issuance Proposal”), and the TCR2 special meeting, at which TCR2 stockholders will be asked to consider and vote on (i) a proposal to adopt the merger agreement (the “merger proposal”) and (ii) a proposal to adjourn or postpone the special meeting of TCR2 stockholders (the “TCR2 special meeting”), or any adjournments or postponements thereof, to another time or place, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement (the “TCR2 adjournment proposal”).
Adaptimmune has supplied all information contained or incorporated by reference in this joint proxy statement/prospectus relating to Adaptimmune and Merger Sub, and TCR2 has supplied all such information relating to TCR2. Adaptimmune and TCR2 have both contributed to such information relating to the merger.
You should rely only on the information contained or incorporated by reference into this joint proxy statement/prospectus. Neither Adaptimmune nor TCR2 authorized anyone to provide you with information that is different from that contained in, or incorporated by reference into, this document. This document is dated April 5, 2023. You should not assume that the information contained in this document is accurate as of any date other than that date. You should not assume that the information incorporated by reference into this document is accurate as of any date other than the date of such incorporated document. Neither the mailing of this joint proxy statement/prospectus to Adaptimmune shareholders nor the delivery by Adaptimmune of either Adaptimmune ADSs or Adaptimmune ordinary shares pursuant to the merger agreement will create any implication to the contrary.
This joint proxy statement/prospectus does not constitute a prospectus within the meaning of section 85 of the U.K. Financial Services and Markets Act 2000 (“FSMA”), and has not been drawn up in accordance with the Prospectus Regulation Rules published by the U.K. Financial Conduct Authority (“FCA”) and a copy has not, and will not be, approved or filed with the FCA. This joint proxy statement/prospectus does not constitute, and Adaptimmune is not making, an offer of transferable securities to the public in the United Kingdom within the meaning of section 102B of FSMA or otherwise.
 

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REFERENCES TO ADDITIONAL INFORMATION
Adaptimmune and TCR2 file annual and other reports and other information with the U.S. Securities and Exchange Commission (the “SEC”). This joint proxy statement/prospectus incorporates by reference important business and financial information about Adaptimmune and TCR2 from documents that are not included in or delivered with this joint proxy statement/prospectus. For a listing of documents incorporated by reference in this joint proxy statement/prospectus, please see the section of this joint proxy statement/prospectus titled “Where You Can Find More Information” beginning on page 214 of this joint proxy statement/prospectus. This information is available for you, without charge, to review through the SEC’s website at www.sec.gov. You also can obtain those documents incorporated by reference in this joint proxy statement/prospectus free of charge by requesting them in writing or by telephone from the appropriate company at the following addresses and telephone numbers:
For information about Adaptimmune:
For information about TCR2:
By Mail: Adaptimmune Therapeutics plc
60 Jubilee Avenue, Milton Park
Abington, Oxfordshire OX14 4RX,
United Kingdom
By Mail: TCR2 Therapeutics Inc.
100 Binney Street, Suite 710
Cambridge, Massachusetts 02142
By Telephone:
(44)
1235 430000
By Telephone:
(617) 949-5200
In addition, you also may obtain additional copies of this joint proxy statement/prospectus or the documents incorporated by reference into this joint proxy statement/prospectus free of charge by contacting Morrow Sodali LLC (“Morrow Sodali”), Adaptimmune’s proxy solicitor, by calling toll free at 1 (800) 662-5200, or Innisfree M&A Incorporated (“Innisfree”), TCR2’s proxy solicitor, by calling toll free at 1 (877) 750-8233. Banks, brokerage firms and other nominees may call collect at 1 (203) 658-9400 for Morrow Sodali, Adaptimmune’s proxy solicitor, or may call collect at 1 (212) 750-5833 for Innisfree, TCR2’s proxy solicitor.
In order for you to receive timely delivery of the documents in advance of the Adaptimmune general meeting to be held on [], 2023 or the TCR2 special meeting to be held on [], 2023, as applicable, please request the documents no later than [], 2023.
 

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
Statements and documents to which Adaptimmune and TCR2 refer you in this joint proxy statement/prospectus as well as oral statements made or to be made by Adaptimmune and TCR2, contain assumptions, expectations, projections, intentions or beliefs about future events that are intended as “forward-looking statements.” All statements included or incorporated by reference in this joint proxy statement/prospectus, other than statements that are historical facts, are forward-looking statements including, without limitation, statements related to (i) satisfaction of closing conditions to the merger, prospective performance and opportunities with respect to Adaptimmune or TCR2, post-closing operations and the outlook for the companies’ businesses; (ii) Adaptimmune’s, TCR2’s or the combined company’s targets, plans, objectives or goals for future operations, including those related to Adaptimmune’s and TCR2’s product candidates, research and development, product candidate introductions and product candidate approvals as well as cooperation in relation thereto; (iii) projections of or targets for revenues, costs, income (or loss), earnings per share, capital expenditures, dividends, capital structure, net financials and other financial measures; and (iv) future economic performance, future actions and outcome of contingencies such as legal proceedings; and the assumptions underlying or relating to such statements. These forward-looking statements are made on the basis of the current beliefs, expectations, and assumptions of management are not guarantees of performance and are subject to significant risks and uncertainty and are subject to change at any time. In the event such risks or uncertainties materialize, Adaptimmune’s, TCR2’s and/or the combined company’s results could be materially adversely affected. The risks and uncertainties include those set forth under “Risk Factors” beginning on page 29 of this joint proxy statement/prospectus and also include, but are not limited to, the following:

failure to consummate the merger as contemplated could negatively impact the price of Adaptimmune ordinary shares and the future business and financial results of the combined company;

the market price of the Adaptimmune ADSs will fluctuate prior to the merger, so TCR2 stockholders cannot be sure of the value of the Adaptimmune ADSs they will receive if the merger is consummated;

the merger remains subject to additional conditions, some of which Adaptimmune and TCR2 cannot control, which could result in the merger not being consummated or being delayed, either of which could negatively impact the share price and future business and operating results of Adaptimmune, TCR2, and/or the combined company;

lawsuits may in the future be filed against Adaptimmune, TCR2 and members of their respective boards of directors challenging the merger, and an adverse ruling in any such lawsuit may delay or prevent the completion of the merger or result in an award of damages against Adaptimmune or TCR2;

the directors and executive officers of TCR2 have interests in the merger that may be different from, or in addition to, those of other TCR2 stockholders, which could have influenced their decisions to support or approve the merger;

the merger agreement restricts Adaptimmune’s and TCR2’s ability to pursue alternatives to the merger, however, in specified circumstances, Adaptimmune or TCR2 may terminate the merger agreement to accept a superior proposal;

if the proposed merger is not completed, each of Adaptimmune and TCR2 will have incurred substantial costs that may adversely affect Adaptimmune’s and TCR2’s respective financial results;

uncertainties associated with the merger may cause a loss of employees and may otherwise affect the future business and operations of Adaptimmune, TCR2 and the combined company;

Adaptimmune and TCR2 may not successfully integrate;

future results of the combined company may differ materially from the unaudited pro forma condensed combined financial statements of Adaptimmune and TCR2 presented in this joint proxy statement/prospectus;

certain contractual counterparties may seek to modify contractual relationships with the combined company, which could have an adverse effect on the combined company’s business and operations;
 
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the market price of Adaptimmune ADSs may be affected by factors different from those affecting the market price of shares of TCR2 Common Stock;

TCR2 stockholders who receive Adaptimmune ADSs in the merger will have rights as holders of Adaptimmune ADSs that differ from their current rights as TCR2 stockholders;

if the merger is consummated, current Adaptimmune shareholders and TCR2 stockholders will have a reduced ownership percentage and voting interest and will exercise less influence over the management and policies of the combined company than they do over Adaptimmune and TCR2, as applicable; and

other risks and uncertainties detailed from time to time in Adaptimmune’s or TCR2’s filings with the SEC, including those risks outlined in “Item 1A: Risk Factors” in Adaptimmune’s Annual Report on Form 10-K for the year ended December 31, 2022, which was filed with the SEC on March 6, 2023 (the “Adaptimmune 10-K”), and in “Item 1A: Risk Factors” in TCR2’s Annual Report on Form 10-K for the year ended December 31, 2022, which was filed with the SEC on March 23, 2023, (the “TCR2 10-K”) and any subsequent filings with the SEC. See the section of this joint proxy statement/prospectus titled “Where You Can Find More Information.”
All forward-looking statements attributable to Adaptimmune, TCR2 or any person acting on their behalf are expressly qualified in their entirety by this cautionary statement. Readers are cautioned not to place undue reliance on these forward-looking statements that speak only as of the date hereof. Except to the extent otherwise required by applicable law, we do not undertake any obligation to republish revised forward-looking statements to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.
SEE ALSO THE SECTION OF THIS JOINT PROXY STATEMENT/PROSPECTUS TITLED “RISK FACTORS.” EXCEPT TO THE EXTENT REQUIRED BY APPLICABLE LAW OR REGULATION, ADAPTIMMUNE AND TCR2 UNDERTAKE NO OBLIGATION TO UPDATE THESE FORWARD-LOOKING STATEMENTS TO REFLECT EVENTS OR CIRCUMSTANCES AFTER THE DATE OF THIS JOINT PROXY STATEMENT/PROSPECTUS OR TO REFLECT THE OCCURRENCE OF UNANTICIPATED EVENTS.
 
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QUESTIONS AND ANSWERS ABOUT THE MERGER
The following questions and answers are intended to address briefly some commonly asked questions that you, as a Adaptimmune shareholder or TCR2 stockholder, may have regarding the merger, the merger agreement and the Adaptimmune general meeting or TCR2 special meeting, as applicable. These questions and answers may not address all questions that may be important to you as a Adaptimmune shareholder or TCR2 stockholder. Please refer to the section titled “Summary” beginning on page 19 of this joint proxy statement/prospectus and the more detailed information contained elsewhere in this joint proxy statement/prospectus, the annexes to this joint proxy statement/prospectus and the documents referred to in this joint proxy statement/prospectus, which you should read carefully and in their entirety. You may obtain the information incorporated by reference in this joint proxy statement/prospectus without charge by following the instructions under the section titled “Where You Can Find More Information” beginning on page 214 of this joint proxy statement/prospectus.
Questions Related to the Merger
Q.
WHAT IS THE PROPOSED MERGER AND WHAT EFFECT WILL IT HAVE ON ADAPTIMMUNE AND TCR2?
A.
The proposed merger is the merger of TCR2 with Merger Sub, an indirect wholly-owned subsidiary of Adaptimmune, pursuant to the merger agreement. If the Allotment Proposal and the Share Issuance Proposal are approved by Adaptimmune shareholders and the merger agreement is adopted by TCR2 stockholders, and the other closing conditions under the merger agreement have been satisfied or waived, Merger Sub will merge with and into TCR2, with TCR2 surviving the merger as a wholly-owned indirect subsidiary of Adaptimmune. As a result of the merger, TCR2 will become a wholly-owned subsidiary of Adaptimmune and will no longer be a publicly held corporation. In addition, following the merger, each issued and outstanding share of TCR2 common stock, par value $0.0001 per share (“TCR2 Common Stock”) will be delisted from Nasdaq and deregistered under the Exchange Act, and TCR2 will no longer file periodic reports with the SEC.
Q.
WHAT PERCENTAGE OF THE COMBINED COMPANY’S ORDINARY SHARES, INCLUDING THOSE REPRESENTED BY ADAPTIMMUNE ADSs, WILL BE ISSUED TO TCR2 STOCKHOLDERS IN CONNECTION WITH THE MERGER?
A.
Adaptimmune will issue Adaptimmune ADSs representing approximately 25% of the combined company’s ordinary shares following the closing of the merger in exchange for shares of TCR2 Common Stock. For a more detailed discussion of the assumptions on which this estimate is based, see the section of this joint proxy statement/prospectus titled “The Merger — Ownership of the Combined Company.
Q.
WHERE CAN I FIND OUT MORE INFORMATION ABOUT ADAPTIMMUNE AND TCR2?
A.
You can find out information about Adaptimmune and TCR2 from the sources described under the section of this joint proxy statement/prospectus titled “Where You Can Find More Information.”
Q.
WHEN IS THE MERGER EXPECTED TO BE COMPLETED?
A.
Adaptimmune and TCR2 intend to complete the merger as soon as possible. Assuming the satisfaction of certain closing conditions, including the (i) approval of the issuance of the Adaptimmune ADSs to be issued in the merger by the Adaptimmune shareholders and (ii) adoption of the merger agreement by TCR2 stockholders, Adaptimmune and TCR2 currently anticipate that the merger will be completed in the second quarter of 2023.
Q.
WHAT ARE THE CONDITIONS TO THE MERGER?
A.
The respective obligations of Adaptimmune, Merger Sub and TCR2 to consummate the merger are subject to the satisfaction or waiver of certain conditions, including, but not limited to, (i)(a) the approval of the Allotment Proposal and the Share Issuance Proposal and (b) the approval of the merger proposal; (ii) effectiveness of the registration statement on Form S-4 of which this joint proxy statement/prospectus is a part, and no stop orders suspending the effectiveness of the Form S-4 have been issued by the SEC and remain in effect; (iii) the absence of any orders, injunctions, judgments, decrees or rulings
 
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that would have the effect of enjoining, restraining, preventing or prohibiting consummation of the merger; (iv) accuracy of the other party’s representations and warranties (subject to certain materiality standards set forth in the merger agreement); (v) authorization for listing on Nasdaq of the Adaptimmune ADSs representing Adaptimmune ordinary shares issuable to TCR2 stockholders and to holders of options to acquire shares of TCR2 Common Stock granted under a TCR2’s equity plan (“TCR2 options”) and restricted stock units, subject to official notice of issuance; (vi) compliance by the other party in all material respects with such other party’s obligations under the merger agreement; (vii) the absence of a material adverse effect on the other party since March 5, 2023; (viii) satisfaction of certain regulatory clearances and (ix) certain contingent liabilities of TCR2 not exceeding $10 million. See the section of this joint proxy statement/prospectus titled “The Merger Agreement — Conditions to Completion of the Merger.
Q.
WHAT HAPPENS IF THE MERGER IS NOT COMPLETED?
A.
If the merger agreement is not adopted by the TCR2 stockholders, the Allotment Proposal or Share Issuance Proposal is not adopted by the Adaptimmune shareholders or if the merger is not completed for any other reason, TCR2 stockholders will not receive Adaptimmune ADSs for their shares of TCR2 Common Stock in connection with the merger. Instead, TCR2 will remain an independent public company and shares of TCR2 Common Stock will continue to be listed and traded on Nasdaq, subject to TCR2’s continued compliance with listing requirements. Under certain specified circumstances, Adaptimmune or TCR2 may be required to disburse a termination fee of $2.4 million to the other party in connection with the termination of the merger agreement, as described under the section titled “The Merger Agreement — Termination Fee.”
Q.
HAVE ANY STOCKHOLDERS COMMITTED TO VOTE FOR THE TRANSACTIONS CONTEMPLATED BY THE MERGER AGREEMENT?
A.
The officers, directors and certain stockholders or shareholders, as applicable, of TCR2 and Adaptimmune have committed to vote for certain proposals to be made at the TCR2 special meeting and the Adaptimmune general meeting, as applicable, pursuant to certain voting agreements, as described in more detail in this joint proxy statement/prospectus under the section entitled “The Voting Agreements.” The TCR2 stockholders who entered into voting agreements beneficially own, in the aggregate, approximately 23.82% of the issued and outstanding shares of TCR2 Common Stock as of March 3, 2023. The Adaptimmune shareholders who entered into voting agreements beneficially own, in the aggregate, approximately 11.7% of the issued and outstanding Adaptimmune ordinary shares, including those represented by Adaptimmune ADSs as of March 3, 2023.
Questions for Adaptimmune Shareholders
Q.
WHY HAVE I RECEIVED THESE MATERIALS?
A.
You are receiving this document because you are a holder of record of Adaptimmune ordinary shares and the Adaptimmune Board is soliciting your proxy to vote at the Adaptimmune general meeting. You are invited to attend the Adaptimmune general meeting to vote on the proposals described in this joint proxy statement/prospectus. However, you do not need to attend the Adaptimmune general meeting to vote your shares. Instead, please submit your proxy online at www.investorcentre.co.uk/eproxy (see instructions on form of proxy). Alternatively, you may simply complete, sign and return the enclosed form of proxy. CREST members may appoint a proxy by using the CREST electronic proxy appointment service. All proxies, however submitted, must be lodged with Adaptimmune’s registrar, Computershare Investor Services PLC (“Computershare”), by no later than [] London time ([] Eastern Time) on [], 2023.
Adaptimmune intends to send this joint proxy statement/prospectus and the accompanying form of proxy on or about [•], 2023 to all holders of record of Adaptimmune ordinary shares as of [•], 2023.
Materials for holders of Adaptimmune ADSs of record, which include the notice from Citibank, N.A. as depositary bank (the “depositary bank”) of the Adaptimmune general meeting, the Adaptimmune general meeting documentation, and an Adaptimmune ADS proxy card, will be mailed on or about [•], 2023 to all holders of Adaptimmune ADSs, including banks, brokers and nominees, who are registered
 
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as holders of Adaptimmune ADSs in the Adaptimmune ADS register by [•] Eastern Time on [•], 2023 (the record date for holders of Adaptimmune ADSs).
Q.
WHAT MATTERS ARE BEING VOTED?
A.
At the Adaptimmune general meeting, Adaptimmune shareholders will be asked to vote upon the following proposals:

Proposal 1 — The Allotment Proposal.   Authorize the Adaptimmune Board (or a duly authorized committee thereof) to allot all Adaptimmune ordinary shares to be issued in connection with the merger (to be represented by Adaptimmune ADSs); and

Proposal 2 — The Share Issuance Proposal.   Approve the issuance of Adaptimmune ordinary shares to be represented by Adaptimmune ADSs in connection with the merger for purposes of applicable Nasdaq rules.
Q.
DOES THE ADAPTIMMUNE BOARD SUPPORT THE MERGER?
A.
Yes. The Adaptimmune Board unanimously determined that the terms of the merger and the other transactions contemplated by the merger agreement are most likely to promote the success of Adaptimmune for the benefit of Adaptimmune shareholders as a whole. See the section of this joint proxy statement/prospectus titled “The Merger — Adaptimmune’s Reasons for the Merger; Recommendation of Adaptimmune’s Board” for more information. The Adaptimmune Board also unanimously resolved to recommend that you vote:

“FOR” the Allotment Proposal; and

“FOR” the Share Issuance Proposal.
Q.
WHAT VOTE IS REQUIRED FOR THE ALLOTMENT PROPOSAL AND THE SHARE ISSUANCE PROPOSAL?
A.
The Allotment Proposal and the Share Issuance Proposal are being proposed as ordinary resolutions. Under English law, assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution. If you fail to submit a proxy or vote in person at the Adaptimmune general meeting, or abstain, or you do not provide your bank, brokerage firm or other nominee with instructions, as applicable, your Adaptimmune ordinary shares will not be voted, and this will not have any effect on the Allotment Proposal and the Share Issuance Proposal.
Q.
WHEN AND WHERE WILL THE ADAPTIMMUNE GENERAL MEETINGS TAKE PLACE?
A.
The Adaptimmune general meeting will be held [•] London time ([•] Eastern Time) on [•], 2023, at Adaptimmune’s corporate headquarters, located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX.
Q.
WHO CAN VOTE AT THE ADAPTIMMUNE GENERAL MEETING?
A.
Holders of Adaptimmune ordinary shares
Only holders of record of Adaptimmune ordinary shares registered in the register of members at [•] London time ([•] Eastern Time) on [•], 2023 will be entitled to vote at the Adaptimmune general meeting.
Whether or not you plan to attend the Adaptimmune general meeting, we urge you to submit your proxy to ensure you count towards the quorum and your vote is counted. Please submit your proxy online at www.investorcentre.co.uk/eproxy (see instructions on form of proxy). Alternatively, please complete and return the enclosed form of proxy. CREST members may appoint a proxy by using the CREST electronic proxy appointment service.
 
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All proxies, however submitted, must be lodged with Adaptimmune’s registrar, Computershare, by no later than [] London time ([] Eastern Time) on [], 2023.
If you sell or transfer your Adaptimmune ordinary shares on or prior to [•], 2023, your form of proxy can no longer be used and if submitted (whether before or after you sell or transfer your Adaptimmune ordinary shares) will be treated as invalid. Please pass this document to the person who arranged the sale or transfer for delivery to the purchaser or transferee. The purchaser or transferee should contact Morrow Sodali, Adaptimmune’s proxy solicitor, to request a new form of proxy for its use.
Beneficial owners of ordinary shares which are registered in the name of a broker, bank or other agent
If, on [•], 2023, your Adaptimmune ordinary shares were held in an account at a brokerage firm, bank or other similar organization and you are the beneficial owner of shares, these proxy materials should be forwarded to you by that organization. The organization holding your account is considered the shareholder of record for purposes of voting at the Adaptimmune general meeting by proxy. You are encouraged to provide voting instructions to your broker or other agent so that they may submit a proxy.
Holders of Adaptimmune ADSs
In order to exercise your vote as a holder of Adaptimmune ADSs, you or your bank, broker or nominee must be registered as a holder of Adaptimmune ADSs in the Adaptimmune ADS register by []. Eastern Time on [], 2023 (the record date for holders of Adaptimmune ADSs).
If you hold Adaptimmune ADSs through a bank, broker or nominee on [], 2023, the materials for holders of Adaptimmune ADSs, which include the depositary bank’s notice of the Adaptimmune general meeting, the Adaptimmune general meeting documentation, and the Adaptimmune ADS proxy card, will be sent to your bank, broker or nominee who should forward the materials to you. Please reach out to your bank, broker or nominee to provide your voting instructions.
Adaptimmune ADS proxy cards submitted by holders of Adaptimmune ADSs must be received by the depositary bank by no later than [] Eastern Time on [], 2023. The depositary bank will collate all votes properly submitted by holders of Adaptimmune ADSs and submit a vote on behalf of all holders of Adaptimmune ADSs.
Contact for holders of Adaptimmune ADSs
If you have queries about how you can deliver voting instructions, please contact Citibank, N.A. — ADR Shareholder Services at tel: +1-877-248-4237 (toll free within the United States) or +1-781-575-4555 (for international callers) or by email: citibank@shareholders-online.com or at Citibank Shareholder Services, P.O. Box 43099, Providence, RI 02940-5000.
Contact at Adaptimmune
If at any point you have any queries, please contact Morrow Sodali, Adaptimmune’s proxy solicitor, by calling toll free at 1 (800) 662-5200.
Q.
HOW MANY VOTES DOES EACH ADAPTIMMUNE SHAREHOLDER HAVE?
A.
On a show of hands, each holder of record of Adaptimmune ordinary shares present in person, and each duly authorized representative present in person of a shareholder that is a corporation, has one vote. On a show of hands, each proxy present in person who has been duly appointed by one or more Adaptimmune shareholders has one vote, but a proxy has one vote for and one vote against a resolution if, in certain circumstances, the proxy is instructed by more than one shareholder to vote in different ways on a resolution. On a poll, each Adaptimmune shareholder present in person or by proxy or (being a corporation) by a duly authorized representative has one vote for each share held by the Adaptimmune shareholder.
Holders of Adaptimmune ADSs have the right, under the deposit agreement, to instruct the depositary bank to exercise the voting rights for the ordinary shares represented by a holder’s Adaptimmune ADSs.
 
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Q.
WHAT CONSTITUTES A QUORUM FOR THE ADAPTIMMUNE GENERAL MEETING?
A.
For the purposes of the Adaptimmune general meeting, a quorate meeting will be formed by two persons being present and between them holding (or being the proxy or corporative representative of the holders of) at least one-third in number of the issued Adaptimmune ordinary shares entitled to vote at the Adaptimmune general meeting.
If you are a holder of record of Adaptimmune ordinary shares, your shares will be counted towards the quorum only if you are present in person or represented by proxy at the Meeting. If you are a beneficial owner of ordinary shares held in an account at a brokerage firm, bank or other similar organization your shares will be counted towards the quorum if your broker or nominee submits a proxy for those shares and the proxy represents the holder at the Adaptimmune general meeting. A member represented by a proxy at the Adaptimmune general meeting will be counted towards the quorum requirement even where the proxy abstains from voting. If a form of proxy does not instruct the proxy how to vote, the proxy may vote as he or she sees fit or abstain in relation to any business of the Adaptimmune general meeting, but the member represented by that proxy at the Adaptimmune general meeting will be counted towards the quorum requirement. If there is no quorum, the Adaptimmune general meeting will stand adjourned to such time, date and place as may be fixed by the chairperson of the Adaptimmune general meeting (being not less than 10 days later), and, if a quorum is not present at the adjourned meeting, the Adaptimmune general meeting will be dissolved.
Where the depositary bank submits votes on behalf of any holders of Adaptimmune ADSs, the number of ordinary shares represented by the Adaptimmune ADSs held by the relevant holders of Adaptimmune ADSs will count towards the quorum.
Q.
HOW DOES AN ADAPTIMMUNE SHAREHOLDER VOTE?
A.
Shareholder of Record.   If you are a holder of record of Adaptimmune ordinary shares, you may have your Adaptimmune ordinary shares voted on matters presented at the Adaptimmune general meeting in any of the following ways:

by proxy — shareholders of record have a choice of voting by proxy:

by submitting the proxy online at www.investorcentre.co.uk/eproxy (see instructions on form of proxy);

by completing, signing and returning the enclosed form of proxy; or

if you are a CREST member, you may appoint a proxy by using the CREST electronic proxy appointment service using the procedures described in the CREST manual (available via www.euroclear.com).

in person — you may attend the Adaptimmune general meeting and cast your vote there.
If your Adaptimmune ordinary shares are held in an account at your bank, brokerage firm or other nominee, please refer to the instructions provided to you by that organization to see which of the above choices are available to you. Please note that if you wish to attend and vote at the Adaptimmune general meeting, your bank, brokerage firm or other nominee will need to appoint you as its proxy (or duly authorized representative).
If you are a holder of record of Adaptimmune ADSs, you can return your executed Adaptimmune ADS proxy card to the depositary bank for tabulation. If you hold your Adaptimmune ADSs through a broker, bank or other organization, that organization can return the Adaptimmune ADS proxy card to the depositary bank following your instruction. The depositary bank will submit your votes to Adaptimmune’s registrar, Computershare, for tabulation.
 
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Q.
HOW CAN I CHANGE MY VOTE OR REVOKE A PROXY?
A.
A registered holder of Adaptimmune ordinary shares can revoke his or her proxy, whether delivered over the internet or by mail, at any time before [•], London Time, on [•], 2023, by voting again through any of the methods available to him or her, by notifying Adaptimmune’s registrar, Computershare, in writing that he or she is revoking his or her proxy, which must be received by Computershare by not less than 48 hours (not including non-business days) before the time of the Adaptimmune general meeting to be effective, or by attending the Adaptimmune general meeting and voting in person. Written notice of revocation should be mailed to: Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England
If Adaptimmune ordinary shares are held in an account at a brokerage firm, bank or similar organization, voting instructions may be changed or revoked by contacting the broker, bank or other nominee holding the shares.
Q.
WHAT HAPPENS IF I SELL MY ADAPTIMMUNE ORDINARY SHARES BEFORE THE ADAPTIMMUNE GENERAL MEETING?
A.
If you sell or transfer your Adaptimmune ordinary shares on or prior to [•], 2023, your form of proxy can no longer be used and if submitted (whether before or after you sell or transfer your Adaptimmune ordinary shares) will be treated as invalid. Please pass this document to the person who arranged the sale or transfer for delivery to the purchaser or transferee. The purchaser or transferee should contact Morrow Sodali, Adaptimmune’s proxy solicitor, to request a new form of proxy for its use.
For holders of Adaptimmune ADSs, the depositary bank will fix the Adaptimmune ADS record date to determine the holders of Adaptimmune ADSs entitled to give instructions for the exercise of voting rights at the Adaptimmune general meeting. Only holders of Adaptimmune ADSs at the close of business Eastern time on such Adaptimmune ADS record date are entitled to give such voting instructions.
Q.
IF AN ADAPTIMMUNE SHAREHOLDER GIVES A PROXY, HOW ARE THE ADAPTIMMUNE ORDINARY SHARES VOTED?
A.
Regardless of the method you choose to vote, the individual named as your proxy on the form of proxy will vote your Adaptimmune ordinary shares in the way that you indicate. When completing the Internet process or the form of proxy, you may specify whether your Adaptimmune ordinary shares should be voted for or against or to abstain from voting on all, some or none of the specific items of business to come before the Adaptimmune general meeting.
If you properly sign your form of proxy but do not mark the boxes showing how your shares should be voted on a matter, the proxy may vote as he or she sees fit or abstain in relation to any business of the Adaptimmune general meeting.
Q.
HOW ARE ADAPTIMMUNE SHAREHOLDER VOTES COUNTED?
A.
For the Allotment Proposal, you may vote “FOR,” “AGAINST” or “VOTE WITHHELD.” Votes will be counted by Computershare, who will separately count “FOR” and “AGAINST” votes, and “VOTES WITHHELD” ​(or abstentions). Votes withheld (or abstentions) and broker non-votes are not votes in law and will not be counted in the calculation of the votes “FOR” and “AGAINST” a resolution.
For the Share Issuance Proposal, you may vote “FOR,” “AGAINST” or “VOTE WITHHELD.” Votes will be counted by Computershare, who will separately count “FOR” and “AGAINST” votes, and “VOTES WITHHELD” ​(or abstentions). Votes withheld (or abstentions) and broker non-votes are not votes in law and will not be counted in the calculation of the votes “FOR” and “AGAINST” a resolution.
Q.
WHO COUNTS THE ADAPTIMMUNE SHAREHOLDER VOTES?
Computershare has been engaged as Adaptimmune’s independent agent to tabulate shareholder votes. If you are a holder of record of Adaptimmune ordinary shares, you can directly submit your proxy online
 
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to Computershare at www.investorcentre.co.uk/eproxy (see instructions on form of proxy) or you can return your executed form of proxy to Computershare for tabulation.
If you hold your Adaptimmune ordinary shares through a broker, your broker will directly submit your proxy to Computershare online or return the form of proxy to Computershare.
If you are a holder of record of Adaptimmune ADSs, you can return your executed Adaptimmune ADS proxy card to the depositary bank for tabulation. If you hold your Adaptimmune ADSs through a broker, bank or other organization, that organization can return the Adaptimmune ADS proxy card to the depositary bank following your instruction. The depositary bank will submit your votes to Computershare for tabulation.
Q.
WHAT IS COMPUTERSHARE’S ROLE?
A.
Computershare is Adaptimmune’s registrar. All communications concerning accounts of registered holders of ordinary shares, including address changes, name changes, ordinary share transfer requirements and similar issues can be handled by contacting Computershare at tel: +44 (0) 370 702 0000 or by writing to Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England.
Communications concerning ADS holder of record accounts can be handled by contacting Citibank, N.A. — ADR Shareholder Services at tel: +1-877-248-4237 (toll free within the United States) or +1-781-575-4555 (for international callers) or by email: citibank@shareholders-online.com or at Citibank Shareholder Services, P.O. Box 43099, Providence, RI 02940-5000.
Q.
HOW CAN AN ADAPTIMMUNE SHAREHOLDER FIND OUT THE RESULTS OF THE VOTING AT THE ADAPTIMMUNE GENERAL MEETING?
A.
Voting results will be announced by the filing of a current report on Form 8-K within four business days after the Adaptimmune general meeting. If final voting results are unavailable at that time, we will file an amended current report on Form 8-K within four business days of the day the final results are available. All reports that Adaptimmune files with the SEC are publicly available when filed. For more information, please see this joint proxy statement/prospectus under the section entitled “Where You Can Find More Information.
Q.
WHO WILL SOLICIT AND PAY THE COST OF ADAPTIMMUNE SOLICITING PROXIES?
A.
Adaptimmune has engaged Morrow Sodali to assist in the solicitation of proxies for the Adaptimmune general meeting. Adaptimmune estimates that it will pay Morrow Sodali a fee not to exceed $15,000. Adaptimmune has agreed to reimburse Morrow Sodali for certain reasonable and documented out-of-pocket fees and expenses, including telephone charges, and also will indemnify Morrow Sodali, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses. Adaptimmune may also reimburse banks, brokers or their agents for their expenses in forwarding proxy materials to beneficial owners of Adaptimmune’s ordinary shares. Adaptimmune’s directors, officers and employees also may solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies. Adaptimmune also has agreed to reimburse the depositary bank for its expenses in sending materials, including Adaptimmune ADS proxy cards, to Adaptimmune ADS holders of record.
Q.
WHAT DO I NEED TO DO NOW?
A.
Even if you are a registered holder of Adaptimmune ordinary shares and plan to attend the Adaptimmune general meeting, after carefully reading and considering the information contained in this joint proxy statement/prospectus, please vote promptly to ensure that your shares are represented at the Adaptimmune general meeting.
If you hold your shares of Adaptimmune ordinary shares in your own name as the shareholder of record, you may submit a proxy to have your shares of Adaptimmune ordinary shares voted at the Adaptimmune general meeting in the following ways: (i) by submitting your proxy online at www.investorcentre.co.uk/eproxy (see instructions on form of proxy), (ii) by completing and signing
 
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the form of proxy and returning it in the envelope provided; or (iii) for CREST members, by appointing a proxy using the CREST electronic proxy appointment service. If you decide to attend the Adaptimmune general meeting and vote in person, your vote at the Adaptimmune general meeting will revoke any proxy previously submitted. If you are a beneficial owner, please refer to the instructions provided by your bank, brokerage firm or other nominee to see which of the above choices are available to you.
Questions for TCR2 Stockholders
Q.
WHY HAVE I RECEIVED THESE MATERIALS?
A.
You are receiving this document because you are a stockholder of record of TCR2 and the board of directors of TCR2 (the “TCR2 Board”) is soliciting your proxy to vote at the TCR2 special meeting, including at any adjournments or postponements thereof. You are invited to attend the TCR2 special meeting to vote on the proposals described in this joint proxy statement/prospectus. However, you do not need to attend the TCR2 special meeting to vote your shares. For additional information see “How does a TCR2 stockholder vote?” below for your options on how to vote your shares of TCR2 Common Stock.
TCR2 intends to send this joint proxy statement/prospectus and the accompanying form of proxy to all TCR2 stockholders of record as of [•], 2023.
Materials for holders of TCR2 stockholders of record, including the notice of meeting incorporating a link to the proxy materials on the TCR2 website, and a TCR2 Common Stock proxy card, will be mailed on or about [•], 2023 to all holders of shares of TCR2 Common Stock, including banks, brokers and nominees, who are registered as holders of shares of TCR2 Common Stock by the TCR2 Record Date.
Q.
WHAT WILL TCR2 STOCKHOLDERS RECEIVE IF THE MERGER IS COMPLETED?
A.
Upon completion of the merger, each issued and outstanding share of TCR2 Common Stock (other than shares of TCR2 Common Stock held by TCR2 as treasury stock and shares of TCR2 Common Stock owned by Adaptimmune, Merger Sub or any direct or indirect wholly-owned subsidiary of Adaptimmune), including shares of TCR2 Common Stock underlying TCR2 restricted stock units that vest upon a change of control, will be converted into the right to receive 1.5117 (the “Exchange Ratio”) Adaptimmune ADSs (the “merger consideration”).
Adaptimmune will not issue fractional Adaptimmune ADSs to holders of shares of TCR2 Common Stock or TCR2 equity awards in connection with the merger, and no such holder will be entitled to receive a fractional Adaptimmune ADS. The number of Adaptimmune ADSs issued to holders of shares of TCR2 Common Stock will be rounded down to the nearest whole Adaptimmune ADS.
Please see the discussion set forth in the section titled “Material U.S. Federal Income Tax Consequences” for a description of the material U.S. federal income tax consequences of the merger. You should consult your own independent tax advisor concerning the U.S. federal income tax consequences to you of the merger, as well as the applicable of state, local and foreign income and other tax laws, in light of your particular circumstances.
Q.
WHAT IS THE TCR2 SPECIAL MEETING?
A.
TCR2 is holding the TCR2 special meeting in order to obtain the stockholder approval necessary to adopt the merger agreement, as amended, a copy of which is attached as Annex A, to this joint proxy statement/prospectus. The merger proposal requires the affirmative vote of holders of a majority of the outstanding shares of TCR2 Common Stock entitled to vote thereon. Separately, TCR2 stockholders will also be asked to approve the TCR2 adjournment proposal. Approval of the TCR2 adjournment proposal requires the affirmative vote of a majority of the votes properly cast on such matter at the TCR2 special meeting by TCR2 stockholders (whether or not a quorum is present). A majority of the votes cast means that the number of votes cast “FOR” the TCR2 adjournment proposal must exceed the number of votes
 
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cast “AGAINST”. It is important that TCR2 stockholders vote their shares of TCR2 Common Stock on each of these matters, regardless of the number of shares owned.
Q.
WHAT MATTERS ARE BEING VOTED?
A.
At the TCR2 special meeting, TCR2 stockholders will be asked to vote upon the following proposals:

Proposal 1 — Adoption of the Merger Agreement.   Adopt the merger agreement; and

Proposal 2 — Approval of Possible Adjournment or Postponement of the TCR2 Special Meeting. Approve any motion to adjourn or postpone the TCR2 special meeting, or any adjournments or postponements thereof, to another time or place, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the TCR2 special meeting to adopt the merger agreement.
Q.
DOES THE TCR2 BOARD OF DIRECTORS SUPPORT THE MERGER?
A.
Yes. The TCR2 Board, unanimously determined that the terms of the merger agreement and the transactions contemplated by the merger agreement, are advisable to, fair to and in the best interests of, TCR2 and TCR2 stockholders. See the section of this joint proxy statement/prospectus titled “The Merger — TCR2’s Reasons for the Merger; Recommendation of TCR2 Board that TCR2 Stockholders Approve the Merger Proposal” for more information. The TCR2 Board unanimously resolved to recommend that TCR2 stockholders vote:

“FOR” the adoption of the merger agreement; and

“FOR” the adjournment or postponement of the TCR2 special meeting, or any adjournments or postponements thereof, to another time and place, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the TCR2 special meeting to adopt the merger agreement.
Q.
WHAT VOTE IS REQUIRED FOR TCR2 STOCKHOLDERS TO ADOPT THE MERGER AGREEMENT?
A.
The adoption of the merger agreement requires the affirmative vote of the holders of a majority of the outstanding shares of TCR2 Common Stock entitled to vote thereon. If you fail to submit a proxy or vote in person at the TCR2 special meeting, or abstain, or you do not provide your bank, brokerage firm or other nominee with instructions, as applicable, this will have the same effect as a vote “AGAINST” the adoption of the merger agreement.
Q.
WHAT VOTE OF TCR2 STOCKHOLDERS IS REQUIRED TO APPROVE THE ADJOURNMENT OR POSTPONEMENT OF THE TCR2 SPECIAL MEETING, IF NECESSARY OR APPROPRIATE, TO SOLICIT ADDITIONAL PROXIES?
A.
Approval of the TCR2 adjournment proposal requires the affirmative vote of a majority of the votes properly cast. A vote to abstain will have no effect this proposal. If you fail to submit a proxy or to vote in person at the TCR2 special meeting or if your shares of TCR2 Common Stock are held through a bank, brokerage firm or other nominee and you do not instruct your bank, brokerage firm or other nominee to vote your shares of TCR2 Common Stock, your shares of TCR2 Common Stock will not be voted, but this will not have any effect on the TCR2 adjournment proposal.
Q.
WHAT IS AN AMERICAN DEPOSITARY SHARE?
A.
An American Depositary Share represents ownership interests in a specified number of securities of a non-U.S. company that are on deposit with the depositary bank. The depositary bank typically appoints a custodian to safekeep the securities on deposit. Adaptimmune has appointed Citibank, N.A. as depositary bank pursuant to a Deposit Agreement, dated May 11, 2015 (the “deposit agreement”). Each Adaptimmune ADS represents the right to receive six Adaptimmune ordinary shares on deposit with the custodian, Citibank, N.A. London Branch. ADSs may be represented by certificates that are commonly known as “American Depositary Receipts” or “ADRs.” For a description of Adaptimmune ADSs, see the section entitled “Description of ADSs.’’
 
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Q.
WHAT ARE THE IMPORTANT DIFFERENCES BETWEEN AN ADAPTIMMUNE ORDINARY SHARE AND AN ADAPTIMMUNE ADS?
A.
While each Adaptimmune ADS represents six Adaptimmune ordinary shares, there are some differences between these two securities. These differences include:

Adaptimmune ADSs are listed on Nasdaq, while Adaptimmune ordinary shares are not listed;

Holders of Adaptimmune ADSs vote the underlying Adaptimmune ordinary shares by instructing the depositary how to vote, while holders of Adaptimmune ordinary shares vote directly at the shareholders meeting; and

Shareholders rights for the Adaptimmune ordinary shares represented by Adaptimmune ADSs are exercisable through the depositary bank only to the extent contemplated in the deposit agreement. To exercise any shareholder rights not contemplated in the deposit agreement, a holder of Adaptimmune ADSs would need to arrange to become a direct shareholder.
For a more detailed discussion about Adaptimmune ordinary shares and Adaptimmune ADSs, see the sections of this joint proxy statement/prospectus titled “Description of Adaptimmune Ordinary Shares” and “Description of Adaptimmune ADSs.”
Q.
WILL TCR2 STOCKHOLDERS BE TAXED ON THE ADAPTIMMUNE ADSs THAT THEY RECEIVE IN THE MERGER?
A.
The receipt of the merger consideration pursuant to the merger is expected to be a taxable transaction for U.S. federal income tax purposes. Generally, for U.S. federal income tax purposes, if you are a U.S. holder (as defined in this joint proxy statement/prospectus under the section titled “Material U.S. Federal Income Tax Consequences”), you are expected to recognize gain or loss equal to the difference between (i) the fair market value (as of the effective time of the merger (the “Effective Time”) of the Adaptimmune ADSs you receive and (ii) your adjusted tax basis in the shares of TCR2 Common Stock exchanged pursuant to the merger. If you are a non-U.S. holder (as defined in this joint proxy statement/prospectus under the section titled “Material U.S. Federal Income Tax Consequences”), the merger generally is not expected to result in tax to you under U.S. federal income tax laws unless you have certain connections with the United States.
TCR2 stockholders should consult their tax advisors as to the particular tax consequences to them of the transaction, including the effect of U.S. federal, state and local tax laws and foreign tax laws.
For a more complete description of the tax consequences of the merger, see the section titled “Material U.S. Federal Income Tax Consequences.
Q.
WHEN AND WHERE WILL THE TCR2 SPECIAL MEETING TAKE PLACE?
A.
The TCR2 special meeting will be held on [•], 2023 at [•] Eastern Time. The TCR2 special meeting will be held entirely via the internet as a virtual meeting. Online access will begin at [•], Eastern Time, and TCR2 encourages the TCR2 stockholders to access the meeting prior to the start time. For instructions on how to attend the TCR2 special meeting online see “How can a TCR2 stockholder vote and attend the TCR2 special meeting online” below.
Q.
DO ANY OF TCR2’S DIRECTORS OR EXECUTIVE OFFICERS HAVE INTERESTS IN THE MERGER THAT MAY DIFFER FROM OR BE IN ADDITION TO MY INTERESTS AS A STOCKHOLDER, GENERALLY?
A.
Yes. In considering the recommendation of the TCR2 Board with respect to the adoption of the merger agreement you should be aware that TCR2’s directors and executive officers have interests in the merger that may be different from, or in addition to, the interests of TCR2 stockholders generally. For TCR2 directors, these interests include the conversion of their options to purchase shares of TCR2 Common Stock into options to purchase Adaptimmune ordinary shares. For TCR2 executive officers, these interests include the conversion of their options to purchase shares of TCR2 Common Stock and TCR2 restricted stock units into options to purchase Adaptimmune ordinary shares. Additionally,
 
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TCR2’s directors and executive officers are covered by certain indemnification and insurance arrangements. Also, under the merger agreement, Adaptimmune agreed to use its reasonable best efforts to appoint Garry Menzel, Andrew Allen and Priti Hedge to the board of directors of the combined company, effective upon the closing of the merger. The TCR2 Board was aware of and considered these interests, among other matters, in evaluating and negotiating the merger agreement and the transactions contemplated by the merger agreement, and in recommending that the merger agreement be adopted by TCR2 stockholders. Additionally information regarding the interests of the TCR2 directors and officers can be found in this joint proxy statement/prospectus under the section entitled “Interests of TCR2’s Directors and Executive Officers in the Merger”.
Q.
CAN TCR2 STOCKHOLDERS SELL THE ADAPTIMMUNE ADSs THAT THEY RECEIVE IN THE MERGER?
A.
Yes, so long as there is market demand for the Adaptimmune ADSs. The Adaptimmune ADSs being issued in the merger are transferable (subject to applicable restrictions under securities laws) and are being registered with the SEC.
Adaptimmune has agreed to use its reasonable best efforts to cause the Adaptimmune ADSs representing Adaptimmune ordinary shares to be authorized for listing, subject to the official notice of issuance, on Nasdaq at or prior to the closing date of the merger (the “closing date”) and thereafter to cause such listing to be maintained for so long as any Adaptimmune ADSs remain outstanding.
There can be no guarantee, however, that the Adaptimmune ADSs will be authorized for listing on Nasdaq and, if listed, there is no assurance that the Adaptimmune ADSs will continue to satisfy the listing requirements of Nasdaq or that a trading market in the Adaptimmune ADSs will develop or exist at any time. Furthermore, no prediction can be made regarding the liquidity of any such market or the prices at which the Adaptimmune ADSs may trade at any point in time.
Q.
WHO CAN VOTE AT THE TCR2 SPECIAL MEETING?
A.
All of the holders of record of shares of TCR2 Common Stock as of the close of business on the TCR2 Record Date, are entitled to receive notice of, and to vote at, the TCR2 special meeting. As of the TCR2 Record Date there were [•] shares of TCR2 Common Stock outstanding. In addition, the TCR2 stockholders list will be available for inspection during the TCR2 special meeting at [•].
Q.
HOW MANY VOTES DO I HAVE?
A.
Each holder of shares of TCR2 Common Stock is entitled to one vote for each share of TCR2 Common Stock owned at the Record Date.
Q.
WHAT CONSTITUTES A QUORUM FOR THE TCR2 SPECIAL MEETING?
A.
A quorum is the minimum number of shares required to be represented, either through virtual attendance or through representation by proxy, to hold a valid meeting.
TCR2’s amended and restated by-laws (“TCR2 by-laws”) provide that a majority of the shares entitled to vote, present in person, by remote communication or represented by proxy, will constitute a quorum for the transaction of business at the TCR2 special meeting.
Under the General Corporation Law of the State of Delaware (the “DGCL”), shares that are voted “ABSTAIN” or “WITHHELD” and broker “non-votes” are counted as present for purposes of determining whether a quorum is present at the TCR2 special meeting. If a quorum is not present, the meeting may be adjourned or postponed until a quorum is obtained.
Q.
HOW CAN A TCR2 STOCKHOLDER VOTE AND ATTEND THE TCR2 SPECIAL MEETING ONLINE?
A.
If your shares of TCR2 Common Stock are registered directly in your name with TCR2’s transfer agent, you are considered to be the stockholder of record with respect to those shares, and the proxy materials and proxy card are being sent directly to you by TCR2. If you are a stockholder of record, you may attend the TCR2 special meeting and vote your shares online at the meeting. Even if you plan to
 
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attend the TCR2 special meeting online, TCR2 requests that you sign and return the enclosed proxy to ensure that your shares will be represented at the TCR2 special meeting if you become unable to attend.
If your shares of TCR2 Common Stock are held in a brokerage account or by another nominee, you are considered the beneficial owner of the shares held in “street name,” and the proxy materials are being forwarded to you by your broker or other nominee together with a voting instruction card. As the beneficial owner, you are also invited to attend the TCR2 special meeting online. Because a beneficial owner is not a stockholder of record, you may not vote your shares at the TCR2 special meeting unless you obtain a proxy from the broker, trustee or nominee that holds your shares, giving you the right to vote the shares at the TCR2 special meeting.
The TCR2 special meeting will be a completely virtual meeting, which will be conducted via live webcast. You will be able to attend the TCR2 special meeting and submit your questions during the meeting by attending virtually at www.proxydocs.com/TCRR. TCR2 stockholders and proxy holders will be able to vote their shares online at the TCR2 special meeting. To attend the TCR2 special meeting online, you will need the control number included on the proxy card or voting instruction card that accompanied your proxy materials. The live webcast will begin promptly at [•], Eastern Time. We encourage you to access the TCR2 special meeting prior to the start time. Online check-in will begin at [•], Eastern Time, and you should allow ample time for the check-in procedures.
Q.
HOW DOES A TCR2 STOCKHOLDER VOTE?
A.
Over the Internet prior to the TCR2 special meeting:   To vote over the internet prior to the TCR2 special meeting, please go to the website listed on your proxy card or voting instruction form and follow the instructions at that site for submitting your proxy electronically. If you vote over the internet prior to the TCR2 special meeting, you do not need to complete and mail your proxy card or vote your proxy by telephone.
By Telephone prior to the TCR2 special meeting:   To vote by telephone, please call the number listed on your proxy card or voting instruction form, and follow the instructions provided on the proxy card. If you vote by telephone, you do not need to complete and mail your proxy card or vote your proxy over the internet.
By Mail prior to the TCR2 special meeting:   To vote using the printed proxy card that may be deliver to you upon request, simply complete, sign and date the proxy card that may be delivered and return it promptly in the postage prepaid envelope provided to you. If you vote by mail, you do not need to vote over the internet or by telephone. If Innisfree receives the proxy card no later than prior to [•], 2023, they will vote your shares as you direct.
Online during the TCR2 special meeting:   If you are a stockholder of record, in order to attend the TCR2 special meeting online and vote online during the TCR2 special meeting, you must register in advance at www.proxydocs.com/TCRR prior to the deadline of [•], 2023 at [•], Eastern Time. You may vote your shares online while virtually attending the TCR2 special meeting by following instructions that will be delivered to you via email. If you vote by proxy prior to the TCR2 special meeting and choose to attend the TCR2 special meeting online, there is no need to vote again during the TCR2 special meeting unless you wish to change your vote. If you are a beneficial owner and not a stockholder of record, you may not vote your shares at the TCR2 special meeting unless you obtain a proxy from the broker, trustee or nominee that holds your shares, giving you the right to vote the shares at the TCR2 special meeting.
Q.
HOW CAN I CHANGE MY VOTE OR REVOKE A PROXY?
A.
You have the right to revoke your proxy by (1) entering a new vote by telephone, over the Internet or by mail, at any time before the 11:59 p.m., Eastern Time, on [•], 2023, (2) attending and voting at the TCR2 special meeting (although attendance at the TCR2 special meeting will not in and of itself revoke a proxy), or (3) by filing an instrument in writing revoking the proxy or another duly executed proxy bearing a later date with TCR2’s Corporate Secretary. Any written notice of revocation or subsequent proxy card should be hand delivered to TCR2’s Corporate Secretary or sent to TCR2’s principal executive officers
 
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at TCR2 Therapeutics Inc., 100 Binney Street, Suite 710, Cambridge, Massachusetts 02142, Attention: Corporate Secretary.
Q.
WHAT HAPPENS IF A TCR2 STOCKHOLDER SELLS HIS/HER SHARES OF TCR2 COMMON STOCK BEFORE THE TCR2 SPECIAL MEETING?
A.
The TCR2 Record Date for TCR2 stockholders entitled to vote at the TCR2 special meeting is earlier than both the date of the TCR2 special meeting and the consummation of the merger. If you transfer your shares of TCR2 Common Stock after the close of business on [•], 2023 (the “TCR2 Record Date”) but before the TCR2 special meeting, unless special arrangements (such as provision of a proxy) are made between you and the person to whom you transfer your shares and each of you notifies TCR2 in writing of such special arrangements, you will retain your right to vote such shares at the TCR2 special meeting but will transfer the right to receive the merger consideration to the person to whom you transfer your shares.
Q.
WHAT HAPPENS IF A TCR2 STOCKHOLDER SELLS HIS/HER SHARES OF TCR2 COMMON STOCK AFTER THE TCR2 SPECIAL MEETING?
A.
If you transfer your shares after the TCR2 special meeting but before the Effective Time, you will have transferred the right to receive the merger consideration to the person whom you transfer your shares. In order to receive the merger consideration, you must hold your shares of TCR2 Common Stock through the completion of the merger.
Q.
IF A TCR2 STOCKHOLDER GIVES A PROXY, HOW ARE THE SHARES OF TCR2 COMMON STOCK VOTED?
A.
Regardless of the method you choose to vote, the individuals named on the enclosed proxy card will vote your shares of TCR2 Common Stock in the way that you indicate. When completing the telephone or Internet processes or the proxy card, you may specify whether your shares of TCR2 Common Stock should be voted for or against or to abstain from voting on all, some or none of the specific items of business to come before the TCR2 special meeting.
If you properly sign your proxy card but do not mark the boxes showing how your shares should be voted on a matter, the shares represented by your properly signed proxy will be voted “FOR” the adoption of the merger agreement and “FOR” the adjournment or postponement of the TCR2 special meeting, or any adjournments or postponement thereof, to another time or place, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the TCR2 special meeting to adopt the merger agreement.
Q.
HOW ARE TCR2 STOCKHOLDER VOTES COUNTED?
A.
For the adoption of the merger agreement, you may vote “FOR,” “AGAINST” or “ABSTAIN.” Votes to abstain and broker non-votes will have the same effect as votes “AGAINST” the adoption of the merger agreement.
For the TCR2 adjournment proposal, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the TCR2 special meeting to adopt the merger agreement, you may vote “FOR,” “AGAINST” or “ABSTAIN.” Votes to abstain and broker non-votes will not have any effect on the proposal.
Q.
WHERE CAN I FIND RESULTS OF THE TCR2 SPECIAL MEETING?
A.
TCR2 intends to publish final voting results in a Current Report on Form 8-K to be filed with the SEC following the TCR2 special meeting. All reports that TCR2 files with the SEC are publicly available when filed. For more information, please see this joint proxy statement/prospectus under the section titled “Where You Can Find More Information.
Q.
WHO WILL SOLICIT AND PAY THE COST OF SOLICITING PROXIES?
A.
TCR2 has engaged Innisfree to assist in the solicitation of proxies for the TCR2 special meeting. TCR2 estimates that it will pay Innisfree a fee not to exceed $100,000. TCR2 has agreed to reimburse Innisfree
 
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for certain reasonable and documented out-of-pocket fees and expenses, including telephone charges, and also will indemnify Innisfree, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses. TCR2 also may reimburse banks, brokers or their agents for their expenses in forwarding proxy materials to beneficial owners of shares of TCR2 Common Stock. TCR2’s directors, officers and employees also may solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies.
Q.
AM I ENTITLED TO EXERCISE APPRAISAL RIGHTS UNDER THE DGCL INSTEAD OF RECEIVING THE PER SHARE MERGER CONSIDERATION FOR MY SHARES OF TCR2 COMMON STOCK?
A.
No. The merger agreement provides that no dissenters’ or appraisal rights will be available with respect to the merger. Furthermore, under the appraisal rights provisions of the DGCL TCR2 stockholders are not entitled to exercise the right of objecting stockholders to receive payment of the fair value of their shares because shares of TCR2 Common Stock are listed on a national securities exchange. See the section of this joint proxy statement/prospectus titled “The Merger Agreement — No Appraisal Rights.”
Q.
WHAT DO I NEED TO DO NOW?
A.
Even if you plan to attend the TCR2 special meeting, after carefully reading and considering the information contained in this joint proxy statement/prospectus, please vote promptly to ensure that your shares are represented at the TCR2 special meeting. If you hold your shares of TCR2 Common Stock in your own name as the stockholder of record, you may submit a proxy to have your shares of TCR2 Common Stock voted at the TCR2 special meeting in the following ways: (i) by telephone by dialing the telephone number specified in the enclosed proxy card, (ii) over the Internet by accessing the website specified on the enclosed proxy card, or (iii) by completing, signing, dating and returning the enclosed proxy card in the accompanying prepaid reply envelope. If you decide to attend the TCR2 special meeting and vote in person, your vote by ballot will revoke any proxy previously submitted. If you are a beneficial owner, please refer to the instructions provided by your bank, brokerage firm or other nominee to see which of the above choices are available to you.
General Questions for both Adaptimmune Shareholders and TCR2 Stockholders
Q.
WHAT IF I HOLD BOTH ADAPTIMMUNE ORDINARY SHARES AND/OR ADAPTIMMUNE ADSs, AND SHARES OF TCR2 COMMON STOCK?
A.
If you are both an Adaptimmune shareholder and/or Adaptimmune ADS holder and a TCR2 stockholder, you will receive separate packages of proxy materials. A vote cast as an Adaptimmune shareholder and/or Adaptimmune ADS holder will not count as a vote cast as a TCR2 stockholder, and a vote cast as a TCR2 stockholder will not count as a vote cast as an Adaptimmune shareholder and/or Adaptimmune ADS holder. Therefore, please follow the instructions received with each set of materials you receive in order to submit separate proxies for your Adaptimmune ordinary shares and/or your Adaptimmune ADSs, and your shares of TCR2 Common Stock.
Q.
WHAT IS THE DIFFERENCE BETWEEN HOLDING SHARES AS A SHAREHOLDER OR STOCKHOLDER OF RECORD AND AS A BENEFICIAL OWNER?
A.
If your Adaptimmune ordinary shares are registered directly in your name with Computershare, the registrar of Adaptimmune, or if your shares of TCR2 Common Stock are registered with the transfer agent of TCR2, as applicable, you are considered the shareholder or stockholder of record, as applicable, with respect to those shares. If you are a shareholder or stockholder of record, as applicable, you may appoint a proxy to vote on your behalf or vote your shares in person at the Adaptimmune general meeting or TCR2 special meeting, as applicable. If you are a holder of record of Adaptimmune ordinary shares or TCR2 Common Stock, you can return your proxy online at [•] to vote your Adaptimmune ordinary shares or your executed TCR2 proxy card in the prepaid envelope you received, as applicable, for tabulation.
 
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If, on [•] or [•], 2023, your Adaptimmune ordinary shares or shares of TCR2 Common Stock, respectively, were held in an account at a brokerage firm, bank or other similar organization and you are the beneficial owner of shares, these proxy materials should be forwarded to you by that organization. The organization holding your account is considered the shareholder or stockholder of record, as applicable, for purposes of voting at the Adaptimmune general meeting or TCR2 special meeting, as applicable, by proxy. You are encouraged to provide voting instructions to your broker or other agent so that they may submit a proxy.
If you are a holder of record of Adaptimmune ADSs on [•], 2023, you can return your executed Adaptimmune ADS proxy card to the depositary bank for tabulation. If you hold Adaptimmune ADSs through a brokerage firm, bank or nominee on [•], 2023, the materials for holders of Adaptimmune ADSs, which include the depositary bank’s notice of the Adaptimmune general meeting, the Adaptimmune general meeting documentation, and the Adaptimmune ADS proxy card, will be sent to that organization. The organization holding your account is considered the Adaptimmune ADS holder of record. Please reach out to that organization to provide your voting instructions.
Q.
IF MY SHARES ARE HELD IN “STREET NAME” BY MY BANK, BROKERAGE FIRM OR OTHER NOMINEE, WILL MY BANK, BROKERAGE FIRM OR OTHER NOMINEE VOTE MY SHARES FOR ME?
A.
Your bank, brokerage firm or other nominee will only be permitted to vote your shares of Adaptimmune ordinary shares, Adaptimmune ADSs or shares of TCR2 Common Stock, as applicable, if you instruct your bank, brokerage firm or other nominee how to vote. You should follow the procedures provided by your bank, brokerage firm or other nominee regarding the voting of your Adaptimmune ADSs or shares of TCR2 Common Stock, as applicable.
In accordance with the rules of the New York Stock Exchange, which also apply to Nasdaq listed companies, banks, brokerage firms and other nominees who hold Adaptimmune ADSs or shares of TCR2 Common Stock, as applicable, in street name for their customers are precluded from exercising their voting discretion with respect to non-routine matters, such as the merger proposal and the TCR2 adjournment proposal. Additionally, for Adaptimmune ordinary shares that are held in an account at a brokerage firm, bank or other similar organization, the shareholder of record is considered such brokerage firm, bank or other similar organization. As a result, absent specific instructions from the beneficial owner of such shares, banks, brokerage firms and other nominees are not empowered to vote such shares (referred to as a broker non-vote). For Adaptimmune shareholders, broker non-votes are not votes in law and will not be counted in the calculation of the votes “FOR” and “AGAINST” a resolution. For TCR2 stockholders, broker non-votes will be the same as a vote “AGAINST” the merger proposal and will not have an effect on the TCR2 adjournment proposal.
With respect to Adaptimmune ADSs, if voting is by poll and the depositary bank does not receive voting instructions from a holder of Adaptimmune ADSs as of the record date for holders of Adaptimmune ADSs on or before the date established by the depositary bank for such purpose, such holder of Adaptimmune ADSs will be deemed, and the depositary bank will deem such holder, to have instructed the depositary bank to give a discretionary proxy to a person designated by Adaptimmune to vote the Adaptimmune ADSs; provided, however, that no such discretionary proxy will be given by the depositary bank with respect to any matter to be voted upon as to which Adaptimmune informs the depositary bank that (i) Adaptimmune does not wish such proxy to be given, (ii) substantial opposition exists, or (iii) the rights of holders of Adaptimmune ADSs may be adversely affected.
Q.
WHAT DO I DO IF I RECEIVE MORE THAN ONE PROXY OR SET OF VOTING INSTRUCTIONS?
A.
If you hold Adaptimmune ordinary shares or Adaptimmune ADSs or shares of TCR2 Common Stock, as applicable, in more than one account, you may receive more than one form of proxy and/or set of voting instructions relating to the Adaptimmune general meeting or the TCR2 special meeting, as applicable. To ensure that all of your shares are voted, please sign, date and return all forms of proxy, Adaptimmune ADS proxy cards or TCR2 proxy cards (as applicable) in accordance with the instructions provided in this joint proxy statement/prospectus or the relevant voting instructions. Please be sure to vote all of your shares.
 
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Q.
WHO CAN HELP ANSWER ANY OTHER QUESTIONS I MIGHT HAVE?
A.
If you are a holder of Adaptimmune ordinary shares or Adaptimmune ADSs and have additional questions about the merger, need assistance in submitting your form of proxy or voting your Adaptimmune ordinary shares or Adaptimmune ADSs, or need additional copies of this joint proxy statement/prospectus or the enclosed proxy card, please contact:
Morrow Sodali LLC
509 Madison Avenue
New York, NY 10022
Toll-free in North America: +1 (800) 662-5200
International: + 1 (203) 658-9400
Email: ADAP@info.morrowsodali.com
If you are a TCR2 stockholder and have additional questions about the merger, need assistance in submitting your proxy or voting your shares of TCR2 Common Stock, or need additional copies of this joint proxy statement/prospectus, you should contact:
Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Stockholders may call toll free: 1 (877) 750-8233
Banks and Brokers may call collect: 1 (212) 750-5833
 
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SUMMARY
The following summary highlights selected information contained in this joint proxy statement/prospectus and does not contain all the information that may be important to you as an Adaptimmune shareholder or TCR2 stockholder. Accordingly, you should read carefully this entire document, including the annexes, exhibits, and documents incorporated by reference herein, and the other documents referred to herein. Items in this summary include a page reference directing you to a more complete description of those items. For information on how to obtain the documents that are on file with the SEC, see the section of this joint proxy statement/prospectus titled “Where You Can Find More Information.”
The Companies (Page 35)
Adaptimmune
Adaptimmune is a clinical-stage biopharmaceutical company focused on providing novel cell therapies to people with cancer. Adaptimmune’s proprietary platform enables it to identify cancer targets, find and develop cell therapy candidates active against those targets and produce therapeutic candidates for administration to patients. Adaptimmune’s cell therapy candidates include genetically engineered T-cell receptors (“TCRs”) and HLA-independent TCRs (“HiTs”) where surface proteins are targeted independently of the peptide-HLA complex. Adaptimmune’s cell therapies are currently manufactured on an autologous or per patient basis, and Adaptimmune has a proprietary allogeneic platform for the development of “off the shelf” cell therapies.
Adaptimmune’s principal executive offices are located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, United Kingdom and its telephone number is (44) 1235-430000.
Merger Sub
Merger Sub was formed by Adaptimmune for the sole purpose of effecting the merger. Merger Sub has not conducted any business and has no assets, liabilities or obligations of any nature other than as set forth in the merger agreement. By operation of the merger, Merger Sub will be merged with and into TCR2, with TCR2 continuing as the surviving corporation and as a wholly-owned direct subsidiary of CM Intermediate Sub II, Inc., a Delaware corporation and wholly-owned subsidiary of Adaptimmune (“CM Intermediate”). Upon completion of the merger, the separate existence of Merger Sub will cease to exist. Merger Sub’s principal executive offices are located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, United Kingdom, and its telephone number is (44) 1235-430000.
TCR2
TCR2 was originally incorporated under the name TCR2, Inc. on May 29, 2015 in the State of Delaware, and subsequently changed its name to TCR2 Therapeutics Inc. on November 14, 2016. TCR2 is a clinical-stage cell therapy company developing a pipeline of novel T cell therapies for cancer patients suffering from solid tumors by powering the T cell receptor (TCR) with its proprietary, first-in-class TCR Fusion Construct T cells (TRuC-T cells). Designed to overcome the limitations of current cell therapy modalities, TCR2’s TRuC-T cells, an HLA-independent T cell therapy platform, recognize and kill cancer cells by harnessing the entire TCR signaling complex, which TCR2 believes is essential for T cell therapies to be effective in patients with solid tumors.
TCR2 is a public company whose shares trade on the Nasdaq under the ticker symbol “TCRR.” TCR2’s principal executive offices are located at 100 Binney Street, Suite 710, Cambridge, Massachusetts 02142, and telephone number is (617) 949-5200.
Additional information about TCR2 can be found on its website at http://www.tcr2.com. The information contained in, or that can be accessed through, TCR2’s website is not intended to be incorporated into this joint proxy statement/prospectus. For additional information about TCR2, see the section of this joint proxy statement/prospectus titled “Where You Can Find More Information.”
 
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Risk Factors (Page 29)
The merger is, and the combined company will be, subject to certain risks. You should carefully read and consider all of the risk factors discussed or incorporated by reference in the section titled “Risk Factors,” which begins on page 29 of this joint proxy statement/prospectus.
Information About the Adaptimmune General Meeting (Page 38)
Time, Place and Purpose of the Adaptimmune General Meeting (Page 38)
The Adaptimmune general meeting will be held [•] London time ([•] Eastern Time) on [•], 2023, at Adaptimmune’s corporate headquarters, located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX.
At the Adaptimmune general meeting, Adaptimmune shareholders will be asked to approve the Allotment Proposal and to approve the Share Issuance Proposal.
Record Date and Quorum (Page 39)
This joint proxy statement/prospectus, including the notice of the Adaptimmune general meeting and associated materials for the Adaptimmune general meeting are being sent or supplied to holders of Adaptimmune ordinary shares as of [•], 2023. Any registered holder in the register of members of Adaptimmune as of [•], 2023 and who continues to be registered as a holder of Adaptimmune ordinary shares in the Adaptimmune register of members as of [•] London time ([•] Eastern Time) on [•], 2023 is entitled to attend and vote at the Adaptimmune general meeting. If any holder of Adaptimmune ordinary shares sells or transfers such Adaptimmune ordinary shares on or prior to [•], the form of proxy of such holder of Adaptimmune ordinary shares can no longer be used and if submitted (whether before or after you sell or transfer your Adaptimmune ordinary shares) will be treated as invalid. The selling or transferring holder of Adaptimmune ordinary shares should pass this document to the person who arranged the sale or transfer for delivery to the purchaser or transferee. The purchaser or transferee should contact Morrow Sodali, Adaptimmune’s proxy solicitor, to request a new form of proxy for its use.
In order to exercise their vote as a holder of Adaptimmune ADSs, the Adaptimmune ADS holder or their bank, broker or nominee must be registered as a holder of Adaptimmune ADSs in the Adaptimmune ADS register by [•] Eastern Time on [•], 2023 (the record date for holders of Adaptimmune ADSs). Any holder of Adaptimmune ADSs through a bank, broker or nominee on [•], 2023, will have the materials for holders of Adaptimmune ADSs, which include the depositary bank’s notice of the Adaptimmune general meeting, the Adaptimmune general meeting documentation, and Adaptimmune ADS proxy card, sent to their bank, broker or nominee who should forward the materials to them. Please reach out to your bank, broker or nominee to provide your voting instructions. Adaptimmune ADS proxy cards submitted by holders of Adaptimmune ADSs must be received by the depositary bank by no later than [•] Eastern Time on [•], 2023.
For the purposes of the Adaptimmune general meeting, a quorate meeting will be formed by two persons being present and between them holding (or being the proxy or corporative representative of the holders of) at least one-third in number of the issued Adaptimmune ordinary shares entitled to vote at the Adaptimmune general meeting. If you are an Adaptimmune shareholder of record, your shares will be counted towards the quorum only if you are present in person or represented by proxy at the Adaptimmune general meeting. If you are a beneficial owner of ordinary shares held in an account at a brokerage firm, bank or other similar organization your shares will be counted towards the quorum if your broker or nominee submits a proxy for those shares and the proxy represents the holder at the Adaptimmune general meeting. A member represented by a proxy at the Adaptimmune general meeting will be counted towards the quorum requirement even where the proxy abstains from voting. If a form of proxy does not instruct the proxy how to vote, the proxy may vote as he or she sees fit or abstain in relation to any business of the Adaptimmune general meeting, but the member represented by that proxy at the Adaptimmune general meeting will be counted towards the quorum requirement. If there is no quorum, the Adaptimmune general meeting will stand adjourned to such time, date and place as may be fixed by the chairperson of the Adaptimmune general
 
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meeting (being not less than 10 days later), and, if a quorum is not present at the adjourned meeting, the Adaptimmune general meeting will be dissolved.
Where the depositary bank submits votes on behalf of any holders of Adaptimmune ADSs, the number of ordinary shares represented by the Adaptimmune ADSs held by the relevant holders of Adaptimmune ADSs will count towards the quorum.
Vote Required (Page 40)
The Allotment Proposal and the Share Issuance Proposal are being proposed as ordinary resolutions. Under English law, assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution.
As of March 28, 2023, the directors and executive officers of Adaptimmune beneficially owned and were entitled to vote, in the aggregate, 13,027,948 Adaptimmune ordinary shares (not including any Adaptimmune ordinary shares deliverable upon the vesting of any restricted stock unit style options or the exercise of any options). This includes Adaptimmune ordinary shares which are represented by Adaptimmune ADSs.
Proxies and Revocation (Page 41)
A registered holder of Adaptimmune ordinary shares can revoke his or her proxy, whether delivered over the internet or by mail, at any time before [•], London Time, on [•], 2023, by voting again through any of the methods available to you, by notifying Adaptimmune’s registrar, Computershare, in writing that you are revoking your proxy, which must be received by Computershare by not less than 48 hours (not including non-business days) before the time of the Adaptimmune general meeting to be effective, or by attending the Adaptimmune general meeting and voting in person. Written notice of revocation should be mailed to: Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England. If Adaptimmune ordinary shares are held in an account at a brokerage firm, bank or similar organization, voting instructions may be changed or revoked by contacting the broker, bank or other nominee holding the shares.
Information About the TCR2 Special Meeting (Page 46)
TCR2 has elected to hold the TCR2 special meeting solely by means of remote communication (via the Internet). The TCR2 special meeting will be held solely via live webcast and there will not be a physical meeting location. TCR2 stockholders will be able to attend the TCR2 special meeting online and vote their shares electronically by visiting www.proxydocs.com/TCRR to register and entering the control number included on their proxy card or on the instructions that accompanied their proxy materials.
To be admitted to the TCR2 special meeting and vote the shares of TCR2 Common Stock, each TCR2 stockholder must register in advance at www.proxydocs.com/TCRR prior to the deadline of [•], 2023 at [•] Eastern Time. The TCR2 stockholder will be required to enter the control number provided in the proxy card at www.proxydocs.com/TCRR and beneficial owners of shares held in street name will need to follow the instructions provided in the voting instructions form by the broker, bank or other nominee that holds their shares. Upon completing the registration, such TCR2 stockholder will receive further instructions via email, including unique links to access the TCR2 special meeting and to submit questions in advance of the TCR2 special meeting. Please see the “Information About the TCR2 Special Meeting” section of this joint proxy statement/prospectus for more details regarding the logistics of the virtual TCR2 special meeting, including the ability of the TCR2 stockholders to submit questions during the TCR2 special meeting, and technical details and support related to accessing the virtual platform.
The purpose of the TCR2 special meeting is to consider and vote on each of the following proposals, each of which is further described in this joint proxy statement/prospectus:

Proposal 1:   Adoption of the Merger Agreement. To consider and vote on the merger proposal; and
 
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Proposal 2:   Adjournment or Postponement of the TCR2 Special Meeting. To consider and vote on the TCR2 adjournment proposal.
A quorum of TCR2 stockholders is necessary to conduct the TCR2 special meeting. The presence, via visiting www.proxydocs.com/TCRR to register and entering your control number included on your proxy card or on the instructions that accompanied your proxy materials (the “special meeting website”) or by proxy, of the holders of a majority of the shares of TCR2 Common Stock entitled to vote at the TCR2 special meeting will constitute a quorum. Shares of TCR2 Common Stock represented at the TCR2 special meeting by attendance via the special meeting website or by proxy and entitled to vote, but not voted, including shares for which a stockholder directs an “abstention” from voting, will be counted for purposes of determining a quorum. However, because all of the proposals for consideration at the TCR2 special meeting are considered “non-routine” matters under the Nasdaq rules (as described below), shares held in “street name” will not be counted as present for the purpose of determining the existence of a quorum unless the stockholder provides their bank, broker or other nominee with voting instructions for at least one of the proposals before the TCR2 special meeting. If a quorum is not present, the TCR2 special meeting will be adjourned or postponed until the holders of the number of shares of TCR2 Common Stock required to constitute a quorum attend.
The Merger and the Merger Agreement (Pages 54 and 106)
The terms and conditions of the merger are contained in the merger agreement, as amended, a copy of which is attached as Annex A hereto. Adaptimmune and TCR2 encourage you to read the merger agreement carefully and in its entirety, as it is the legal document that governs the merger.
The merger agreement provides that, subject to the terms and conditions of the merger agreement, Merger Sub will be merged with and into TCR2, with TCR2 continuing as the surviving corporation and as a wholly-owned indirect subsidiary of Adaptimmune.
Adaptimmune Voting Agreements (Page 133)
In connection with the merger agreement, Adaptimmune and TCR2 entered into voting and support agreements (the “Adaptimmune Voting Agreements”) with certain shareholders of Adaptimmune (the “Adaptimmune Supporting Holders”). The Adaptimmune Supporting Holders beneficially own, in the aggregate, approximately 11.7% of the issued and outstanding Adaptimmune ordinary shares, including those represented by Adaptimmune ADSs (the “Adaptimmune Covered Shares”) as of March 3, 2023, the last trading day before the public announcement of the merger agreement.
Adaptimmune Supporting Holders have separately agreed, pursuant to their respective Adaptimmune Voting Agreement, among other things, to vote all Adaptimmune Covered Shares, beneficially owned and entitled to vote at any meeting of Adaptimmune’s shareholders at which the approval of the Allotment Proposal or the Share Issuance Proposal are to be voted on, in favor of the Allotment Proposal and Share Issuance Proposal. Each Adaptimmune Supporting Holder has also agreed not to transfer, or enter into an agreement to transfer, their Adaptimmune Covered Shares, with certain limited exceptions, prior to the Adaptimmune general meeting.
See Annex B and the section of this joint proxy statement/prospectus titled “—Adaptimmune Voting Agreements.
TCR2 Voting Agreements (Page 133)
In connection with the merger agreement, Adaptimmune and TCR2 entered into voting and support agreements (the “TCR2 Voting Agreements”) with certain stockholders of TCR2 (the “TCR2 Supporting Holders”). The TCR2 Supporting Holders beneficially own, in the aggregate, approximately 23.82% of the issued and outstanding shares of TCR2 common stock (the “TCR2 Covered Shares”) as of March 3, 2023, the last trading day before the public announcement of the merger agreement.
TCR2 Supporting Holders have separately agreed, pursuant to their respective TCR2 Voting Agreement, among other things, to vote all TCR2 Covered Shares, beneficially owned and entitled to vote at any meeting
 
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of TCR2 stockholders at which the approval of the merger proposal or TCR2 adjournment proposal are to be voted on, in favor of the merger proposal and TCR2 adjournment proposal. Each TCR2 Supporting Holder has also agreed not to transfer, or enter into an agreement to transfer, their TCR2 Covered Shares, with certain limited exceptions, prior to the TCR2 special meeting.
See Annex C and the section of this joint proxy statement/prospectus titled “—TCR2 Voting Agreements.
Opinion of Adaptimmune’s Financial Advisor (Page 75)
Adaptimmune has engaged Cowen and Company, LLC (“TD Cowen”) as its financial advisor in connection with the merger. In connection with this engagement, TD Cowen delivered a written opinion, dated March 5, 2023, to the Adaptimmune Board as to the fairness, from a financial point of view and as of the date of such opinion, to Adaptimmune of the Exchange Ratio provided for pursuant to the merger agreement. The full text of TD Cowen’s written opinion, dated March 5, 2023, is attached as Annex D to this joint proxy statement/prospectus and is incorporated herein by reference. The summary of TD Cowen’s written opinion set forth herein is qualified in its entirety by reference to the full text of such opinion. TD Cowen’s analyses and opinion were prepared for and addressed to the Adaptimmune Board and were directed only to the fairness, from a financial point of view, to Adaptimmune of the Exchange Ratio. TD Cowen’s opinion did not in any manner address Adaptimmune’s underlying business decision to effect the merger or the relative merits of the merger as compared to other business strategies or transactions that might be available to Adaptimmune. The Exchange Ratio was determined through negotiations between Adaptimmune and TCR2, and TD Cowen’s opinion does not constitute a recommendation to any securityholder or any other person as to how to vote or act with respect to the merger or otherwise. For additional information relating to TD Cowen’s opinion, see the section entitled “The Merger—Opinion of Adaptimmune’s Financial Advisor” beginning on page 75 and Annex D to this proxy statement/prospectus.
Opinion of TCR2’s Financial Advisor (Page 90)
On March 5, 2023, Piper Sandler & Co. (“Piper Sandler”) rendered its oral opinion to the TCR2 Board (which was subsequently confirmed in writing by delivery of Piper Sandler’s written opinion dated that same date) to the effect that, as of March 5, 2023, and based upon and subject to the various assumptions and limitations set forth therein, the Exchange Ratio was fair, from a financial point of view, to the holders of TCR2 Common Stock with the right to receive Adaptimmune ADSs in the merger.
Piper Sandler’s opinion was directed to the TCR2 Board, and addressed solely the fairness, from a financial point of view, to the holders of TCR2 Common Stock with the right to receive Adaptimmune ADSs in the merger, of the Exchange Ratio set forth in the merger agreement and did not address any other terms or agreement relating to the merger or any other terms of the merger agreement. The summary of Piper Sandler’s opinion in this joint proxy statement/prospectus is qualified in its entirety by reference to the full text of its written opinion, which is included as Annex E to this joint proxy statement/prospectus and sets forth the assumptions made, procedures followed, matters considered and limitations on the scope of the review undertaken by Piper Sandler in preparing its opinion. However, neither Piper Sandler’s written opinion nor the summary of its opinion and the related analyses set forth in this joint proxy statement/prospectus is intended to be, and they do not constitute, a recommendation to any TCR2 stockholder as to how such stockholder should act or vote with respect to the merger or any other matter.
See Annex E and the section of this joint proxy statement/prospectus entitled “The Merger—Opinion of TCR2’s Financial Advisor.”
Recommendation of the Adaptimmune Board (Page 71)
The Adaptimmune Board unanimously recommends that you vote “FOR” the Allotment Proposal and “FOR” the Share Issuance Proposal. For a description of factors considered by the Adaptimmune Board in reaching its decision to approve the merger agreement and the transactions contemplated thereby, including the merger and the share issuance, and additional information on the recommendation of the Adaptimmune Board, see the section of this joint proxy statement/prospectus titled “The Merger—Adaptimmune’s Reasons for the Merger; Recommendation of the Adaptimmune Board.
 
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Recommendation of the TCR2 Board (Page 86)
The TCR2 Board unanimously recommends that you vote “FOR” the merger proposal and “FOR” the TCR2 adjournment proposal. For a description of factors considered by the TCR2 Board in reaching its decision to approve the merger agreement and the transactions contemplated thereby, including the merger, and additional information on the recommendation of the TCR2 Board, see the section of this joint proxy statement/prospectus titled “The Merger—TCR2’s Reasons for the Merger; Recommendation of TCR2’s Board that TCR2 Stockholders Approve the Merger Proposal.
Interests of Adaptimmune Directors and Executive Officers in the Merger (Page 141)
Other than with respect to continued service for, employment by and/or the right to continued indemnification by the combined company, and the rights and obligations of the Adaptimmune Supporting Holders under the Adaptimmune Voting Agreements, as of the date of this joint proxy statement/prospectus, Adaptimmune directors and executive officers do not have interests in the merger that are different from, or in addition to, the interests of other Adaptimmune shareholders generally. For more information, see the section of this joint proxy statement/prospectus titled “Interests of Adaptimmune Directors and Executive Officers in the Merger.
Interests of TCR2 Directors and Executive Officers in the Merger (Page 142)
Other than with respect to continued service for, employment by and/or the right to continued indemnification by the combined company, and the rights and obligations of the TCR2 Supporting Holders under the TCR2 Voting Agreements, as of the date of this joint proxy statement/prospectus, TCR2 directors and executive officers do have interests in the merger that are different from, or in addition to, the interests of other TCR2 stockholders generally. For more information, see the section of this joint proxy statement/prospectus titled “Interests of TCR2 Directors and Executive Officers in the Merger.
Governance Matters After the Merger (Page 102)
Pursuant to the merger agreement, Adaptimmune has agreed to use its reasonable best efforts so that, at of the Effective Time, the number of directors of the Adaptimmune Board will consist of up to nine members, of which three are members of the TCR2 Board, as constituted on March 5, 2023, designated by TCR2 and reasonably acceptable to Adaptimmune.
Ownership of Adaptimmune After the Merger (Page 103)
Upon completion of the merger, the Adaptimmune shareholders immediately prior to the merger are expected to own approximately 75% of the combined company’s ordinary shares and TCR2 stockholders immediately prior to the merger are expected to own approximately 25% of the combined company’s ordinary shares.
Regulatory Approvals and Related Matters (Page 103)
Pursuant to the terms and conditions of the merger agreement, each of Adaptimmune and TCR2 have agreed to use their respective reasonable best efforts to take, or cause to be taken, all actions and to do, or cause to be done, all things necessary, proper or advisable under applicable laws in connection with the merger and the other transactions contemplated by the merger agreement, including (i) making any filings required by applicable antitrust laws as promptly as reasonably practicable following the date of the merger agreement, (ii) supplying as promptly as practicable any additional information and documentary material required pursuant to any antitrust law and (iii) satisfying certain regulatory matters. No filings under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (the “HSR Act”) are required for the merger.
Subject to the prior good faith cooperation of TCR2 and its subsidiaries, Adaptimmune has agreed to take, and to cause each of its subsidiaries and affiliates to take, reasonable actions necessary to obtain any consents, clearances or approvals required under or in connection with the antitrust laws. Adaptimmune is not required to sell, divest or otherwise dispose of, hold separate, enter into any license or similar agreement with respect to, restrict the ownership or operation of, or agree to sell, divest or otherwise dispose of, hold
 
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separate, enter into any license or similar agreement with respect to, or restrict the ownership or operation of, any assets or businesses of TCR2 or any of its subsidiaries or of Adaptimmune or any of its affiliates or subsidiaries. For more information, see the section of this joint proxy statement/prospectus titled “The Merger — Regulatory Approvals and Related Matters.”
Closing and Effective Time of the Merger (Page 102)
Subject to the satisfaction or waiver of the closing conditions, including the approval by Adaptimmune shareholders of the Allotment Proposal and the Share Issuance Proposal and approval by TCR2 stockholders of the adoption of the merger agreement and the merger, Adaptimmune and TCR2 expect that the merger will be completed in the second quarter of 2023. The merger agreement provides that the closing will occur as early as practicable on a date to be specified by the parties to the merger agreement and no later than the second business day after satisfaction or waiver of all of the conditions to closing described under the section titled, “The Merger Agreement — Conditions to Completion of the Merger,” other than those conditions that by their nature may only be satisfied at the closing, but subject to the satisfaction or waiver of such conditions at the closing.
Conditions to Completion of the Merger (Page 127)
The obligations of Adaptimmune, Merger Sub and TCR2 to consummate the merger are subject to the satisfaction or waiver, if permitted by applicable law, of the following conditions:

approval by Adaptimmune shareholders of (A) the Allotment Proposal (B) the Share Issuance Proposal, and (C) any other resolutions required by law or the rules and regulations of Nasdaq or other listing authority;

approval by TCR2 stockholders of the merger proposal;

the registration statement on Form S-4 becoming effective under the Securities Act, and no stop order suspending the effectiveness of the registration statement shall have been issued by the SEC and remain in effect;

no restraints or laws shall be in effect enjoining, restraining, preventing or prohibiting consummation of the merger or making consummation of the merger illegal;

certain regulatory matters shall have been satisfied; and

the Adaptimmune ADSs issuable to TCR2 stockholders and to holders of TCR2 options and restricted stock units with respect to shares of TCR2 Common Stock (“TCR2 restricted stock units”) shall have been authorized for listing on Nasdaq, subject to official notice of issuance.
In addition, the obligations of Adaptimmune and Merger Sub to consummate the merger are subject to satisfaction or waiver, if permitted by applicable law, of the following additional conditions:

the representations, warranties and covenants of TCR2 made in the merger agreement being true and correct, subject to the standards and qualifications set forth in the merger agreement;

performance by TCR2 in all material respects the covenants and obligations required to be performed by it under the merger agreement at or prior to the closing of the merger;

the absence of any effect, event, occurrence, development or change that has a material adverse effect on the financial condition, assets, liabilities, business or results of operations of TCR2 (a “TCR2 Material Adverse Effect”) since the date of the merger agreement;

the delivery by TCR2 to Adaptimmune of a certificate dated the closing date satisfying the requirements set forth in Treasury Regulations Sections 1.1445-2(c)(3) and 1.897-2(h) certifying that TCR2 is not nor has been a “U.S. real property holding corporation” at any time during the five years preceding the date of the certificate;

the delivery by TCR2 to Adaptimmune of a certificate dated as of the closing date signed on its behalf by its Chief Executive Officer or Chief Financial Officer to the effect that the conditions have been satisfied; and
 
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certain contingent liabilities of TCR2 are no more than $10 million as of closing.
In addition, the obligations of TCR2 to consummate and effect the merger are subject to satisfaction or waiver, if permitted by applicable law, of the following additional conditions:

the representations, warranties and covenants of Adaptimmune and Merger Sub made in the merger agreement being true and correct, subject to the standards and qualifications set forth in the merger agreement;

performance by each of Adaptimmune and Merger Sub in all material respects the covenants and obligations required to be performed by it under the merger agreement at or prior to the closing of the merger;

the absence of any effect, event, occurrence, development or change that has a material adverse effect on the financial condition, assets, liabilities, business or results of operations of Adaptimmune (an “Adaptammune Material Adverse Effect”) since the date of the merger agreement;

the delivery by Adaptimmune to TCR2 of a certificate dated as of the closing date signed on its behalf by its Chief Executive Officer or Chief Financial Officer to the effect that the conditions have been satisfied; and

the appointment of TCR2’s director nominees to the Adaptimmune Board, effective as of the closing.
Termination of the Merger Agreement (Page 129)
Adaptimmune and TCR2 may, by mutual written consent, terminate the merger agreement and abandon the merger and the other transactions contemplated thereby at any time before the Effective Time, whether before or after the required Adaptimmune shareholder or TCR2 stockholder approval is obtained.
The merger agreement may also be terminated and the transactions contemplated thereby may be abandoned, except as otherwise provided in the merger agreement:

By either Adaptimmune or TCR2, if:

(a)   a restraint prohibiting the merger is in effect and has become final and non-appealable;

(b)   the Effective Time has not occurred by 5:00 p.m. Eastern time on September 5, 2023; provided, that this the right to terminate the merger agreement will not be available to a party if the failure by such party to perform any of its obligations under the merger agreement has been the principal cause of the failure of any condition;

(c)   the TCR2 special meeting concluded and the required approval by TCR2 stockholders was not obtained at such meeting; provided, that this right to terminate the merger agreement is not available to TCR2 if the failure by TCR2 to perform any of its obligations under the merger agreement has been the principal cause of the failure to obtain the required approval by TCR2 stockholders; or

(d)   the Adaptimmune general meeting concluded and the required approval by Adaptimmune shareholders was not obtained at such meeting; provided, that this right to terminate the merger agreement is not available to Adaptimmune if the failure by Adaptimmune or Merger Sub to perform any of their obligations under the merger agreement has been the principal cause of the failure to obtain the required approval by Adaptimmune shareholders.

By Adaptimmune:

(a)   if there has been a breach of, or inaccuracy in, any representation, warranty, covenant or agreement of TCR2 set forth in the merger agreement, which breach or inaccuracy would result in a failure of a condition (other than the condition regarding the FIRPTA certificate) of closing of the merger and to the extent such breach or inaccuracy has not been cured such that such condition would be capable of satisfaction at the closing of the merger within 30 days after the receipt of notice thereof or such breach or inaccuracy is not reasonably capable of being so cured within such 30-day period; provided, however, that Adaptimmune shall not be entitled
 
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to this termination right if either Adaptimmune or Merger Sub is in breach of its representations, warranties, covenants or agreements set forth in the merger agreement such that TCR2 would be entitled to terminate the merger agreement;

(b)   prior to obtaining the required approval from TCR2 stockholders, if the TCR2 Board effected an adverse recommendation change; or

(c)   prior to obtaining the required approval from its shareholders, in order to enter into a definitive agreement providing for a superior proposal.

By TCR2:

(a)   if there has been a breach of, or inaccuracy in, any representation, warranty, covenant or agreement of Adaptimmune or Merger Sub in the merger agreement, which breach or inaccuracy would result in a failure of a condition of closing of the merger to be satisfied at the closing of the merger and to the extent such breach or inaccuracy has not been cured such that such condition would be capable of satisfaction at the closing of the merger within 30 days after the receipt of notice thereof or such breach or inaccuracy is not reasonably capable of being so cured within such 30-day period; provided, however, that TCR2 shall not be entitled to this termination right if TCR2 is in breach of its representations, warranties, covenants or agreements set forth in the merger agreement such that Adaptimmune would be entitled to terminate the merger agreement;

(b)   prior to obtaining the required approval from the Adaptimmune shareholders, if the Adaptimmune Board shall have effected an adverse recommendation change; or

(c)   prior to obtaining the required approval from its stockholders, in order to enter into a definitive agreement providing for a superior proposal.
All costs and expenses incurred in connection with the merger agreement and the transactions contemplated thereby will be paid by the party incurring such expenses whether or not the merger is consummated. The merger agreement also provides that under certain circumstances described, Adaptimmune or TCR2, as applicable, will be required to pay a termination fee equal to $2.4 million. For a more complete discussion of termination fee and expenses, see the section of this joint proxy statement/prospectus titled “The Merger Agreement — Termination Fee.” In the event of termination of the merger agreement, each party will remain liable for fraud or any intentional breach of its representations, warranties, covenants or agreements.
No Appraisal Rights (Page 106)
No appraisal rights shall be available to the TCR2 stockholders in connection with the merger.
Nasdaq Listing of the Adaptimmune ADSs; Delisting and Deregistration of TCR2 Common Stock (Page 104)
It is a condition to the merger that the Adaptimmune ADSs representing Adaptimmune ordinary shares issuable in connection with the merger be authorized for listing on Nasdaq, subject to official notice of issuance. Adaptimmune has agreed to use its reasonable best efforts to cause the Adaptimmune ADSs representing Adaptimmune ordinary shares to be authorized for listing on Nasdaq, subject to official notice of issuance, prior to the Effective Time of the merger.
Accounting Treatment (Page 105)
The merger is expected to be accounted for as a business combination using the acquisition method with Adaptimmune as the accounting acquirer in accordance with ASC 805. Under this method of accounting, the merger consideration will be allocated to TCR2’s assets acquired and liabilities assumed based upon their estimated fair values at the date of completion of the merger.
In addition, the acquisition method of accounting requires the acquirer to recognize the consideration transferred at fair value. Any differences between the estimated fair value of the merger consideration and the estimated fair value of the assets acquired and liabilities assumed will be recorded as goodwill.
 
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Alternatively, any excess of the estimated fair value of such assets and liabilities over the merger consideration would be recorded as bargain purchase gain.
Comparison of Holders’ Rights (Page 180)
Upon completion of the merger, holders of shares of TCR2 Common Stock receiving Adaptimmune ADSs will become holders of Adaptimmune ADSs. The rights of holders of Adaptimmune ordinary shares are governed by English law, including the provisions of the U.K. Companies Act 2006 (the “Companies Act 2006”), and by Adaptimmune’s articles of association. These rights differ in certain respects from the rights of shareholders in typical U.S. corporations organized in, for example, Delaware. In addition, holders of Adaptimmune ADSs will be able to exercise the shareholder rights for the Adaptimmune ordinary shares represented by such Adaptimmune ADSs through the depositary bank, only to the extent contemplated by the deposit agreement. For more information, see the description of Adaptimmune ADSs contained in the Adaptimmune Annual Report on Form 10-K, filed on March 6, 2023, which is incorporated into this document by reference, as well as the section of this joint proxy statement/prospectus titled “Description of Adaptimmune ADSs” for a discussion of the terms of the Adaptimmune ADSs and the material rights of owners of Adaptimmune ADSs.
In addition, only registered holders of Adaptimmune ordinary shares are afforded the rights of shareholders under English law and Adaptimmune’s articles of association. Because the depositary bank holds the Adaptimmune ordinary shares represented by Adaptimmune ADSs through a custodian which is a participant in the CREST securities settlement system, and the custodian or its nominee is the registered holder of the Adaptimmune ordinary shares represented by Adaptimmune ADSs, the holders of Adaptimmune ADSs must rely on the depositary bank to exercise the rights of a shareholder via its custodian.
Holders of Adaptimmune ADSs are entitled to present Adaptimmune ADSs to the depositary bank for cancellation and withdraw the corresponding number of underlying Adaptimmune ordinary shares but would be responsible for fees relating to such exchange. Fees and charges are also payable by Adaptimmune ADS holders in relation to certain other depositary services.
There are certain differences in the rights of TCR2 stockholders under Delaware law, the TCR2 charter and TCR2 by-laws and of the holders of Adaptimmune ADSs. See the section of this joint proxy statement/prospectus titled “Comparison of Holders’ Rights.
Material U.S. Federal Income Tax Consequences (Page 135)
The receipt by TCR2 stockholders of the per share merger consideration pursuant to the merger is expected to be a taxable transaction for U.S. federal income tax purposes. Generally, for U.S. federal income tax purposes, if you are a U.S. Holder (as defined in the section titled “Material U.S. Federal Income Tax Consequences” of this joint proxy statement/prospectus) you are expected to recognize gain or loss equal to the difference between (i) the fair market value (as of the Effective Time) of the Adaptimmune ADSs received pursuant to the merger and (ii) your adjusted tax basis in shares of TCR2 Common Stock you exchanged pursuant to the merger. If you are a non-U.S. Holder (as defined in the section titled “Material U.S. Federal Income Tax Consequences” of this joint proxy statement/prospectus), the merger generally is not expected to result in tax to you under U.S. federal income tax laws unless you have certain connections with the United States.
TCR2 stockholders should consult their tax advisors as to the particular tax consequences to them of the merger, including the effect of U.S. federal, state and local tax laws and foreign tax laws. For a more complete description of the tax consequences of the merger, see the section of this joint proxy statement/prospectus titled “Material U.S. Federal Income Tax Consequences.”
 
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RISK FACTORS
Before you vote, you should read carefully this joint proxy statement/prospectus and all other documents to which this joint proxy statement/prospectus refers. In addition to the risk factors set forth below, you should read and consider all of the other risk factors specific to each of Adaptimmune and TCR2 because those risks will also affect the combined company after consummation of the merger, as described below, and as described in Part I, Item 1A of the Adaptimmune 10-K and the TCR2 10-K and each of Adaptimmune’s and TCR2’s other documents that have been filed with the SEC and which are incorporated by reference into this joint proxy statement/prospectus.
If any of the risks described below or in the documents incorporated by reference into this joint proxy statement/prospectus occurs, the respective businesses, financial results, financial conditions, operating results or share prices of Adaptimmune, TCR2 and/or the combined company could be materially adversely affected. Adaptimmune shareholders and TCR2 stockholders should also carefully consider the following factors:
Risks Related to the Proposed Merger
Failure to consummate the merger as contemplated could negatively impact the price of Adaptimmune ordinary shares and the future business and operating results of the combined company.
The consummation of the merger may be delayed, the merger may be consummated on terms different than those contemplated by the merger agreement, or the merger may not be consummated at all. Failure to consummate the merger would prevent Adaptimmune shareholders from realizing the anticipated benefits of the merger. In addition, the consideration offered by Adaptimmune reflects a valuation of TCR2 significantly in excess of the price at which shares of TCR2 Common Stock were trading prior to the public announcement of Adaptimmune’s interest in the potential merger. The current market price of shares of TCR2 Common Stock may reflect a market assumption that the merger will occur, and a failure to consummate the merger could result in a significant decline in the market price of shares of TCR2 Common Stock and a negative perception of TCR2 generally. Any delay in the consummation of the merger or any uncertainty about the consummation of the merger could also negatively impact the share price and future business and financial results of Adaptimmune, TCR2 and/or the combined company.
The market price of the Adaptimmune ADSs will fluctuate prior to the merger, so TCR2 stockholders cannot be sure of the value of the Adaptimmune ADSs they will receive if the merger is consummated.
If the merger is consummated, each issued and outstanding share of TCR2 Common Stock will be converted into the right to receive the merger consideration. Because the number of Adaptimmune ADSs being offered as consideration is fixed, the market value of the per share stock consideration will be based on the value of Adaptimmune ADSs at the time the per share stock consideration in the merger is paid. If the market price of Adaptimmune ADSs declines, TCR2 stockholders could receive less value for their shares of TCR2 Common Stock upon the consummation of the merger than the implied value of such shares as of the date the merger was announced, the date of the TCR2 stockholders’ meeting, or as of the date of this joint proxy statement/prospectus.
The market price of Adaptimmune ADSs may fluctuate due to a variety of factors that are beyond Adaptimmune’s control, including general market and economic conditions, changes in business prospects, catastrophic events, both natural and man-made, and regulatory considerations. In addition, the market price of the Adaptimmune ADSs may significantly fluctuate during the period of time between the date of the merger agreement and the consummation of the merger, as a result of uncertainty regarding the transactions contemplated by the merger agreement, market perception of the synergies and cost savings expected to be achieved related to the merger, changes to the ongoing business of Adaptimmune or TCR2, including any actions taken by Adaptimmune’s or TCR2’s customers, suppliers, distributors, partners, employees, investors and governmental authorities as a result of the merger announcement, or actions taken by Adaptimmune or TCR2 in connection with the merger.
Because the merger will not be completed until certain conditions have been satisfied or, where relevant, waived (see the section of this joint proxy statement/prospectus titled “The Merger Agreement — Conditions to Completion of the Merger”), a period of time, which may be significant, may pass between the
 
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date of signing the merger agreement, the date of the Adaptimmune general meeting and TCR2 special meeting, and the completion of the merger. Therefore, at the time you vote your shares of TCR2 Common Stock, you will not know the exact market value of per share stock consideration that will be issued if the merger is completed.
TCR2 stockholders are urged to obtain current market prices for Adaptimmune ADSs and shares of TCR2 Common Stock. See the section of this joint proxy statement/prospectus titled “Comparative Per Share Market Price and Dividend Information.”
The merger remains subject to additional conditions, some of which Adaptimmune and TCR2 cannot control, which could result in the merger not being consummated or being delayed, either of which could negatively impact the share price and future business and operating results of Adaptimmune, TCR2, and/or the combined company.
The merger is subject to the satisfaction or waiver of other conditions in addition to the approval of governmental authorities described above, including, but not limited to, (i)(a) the approval of the Allotment Proposal and the Share Issuance Proposal and (b) the adoption of the merger proposal; (ii) effectiveness of the registration statement on Form S-4 of which this joint proxy statement/prospectus is a part, and no stop orders suspending the effectiveness of the Form S-4 have been issued by the SEC and remain in effect; (iii) the absence of any orders, injunctions, judgments, decrees or rulings that would have the effect of enjoining, restraining, preventing or prohibiting consummation of the merger; (iv) accuracy of the other party’s representations and warranties (subject to certain materiality standards set forth in the merger agreement); (v) authorization for listing on Nasdaq of the Adaptimmune ADSs representing Adaptimmune ordinary shares issuable to TCR2 stockholders and to holders of TCR2 options and restricted stock units, subject to official notice of issuance; (vi) compliance by the other party in all material respects with such other party’s obligations under the merger agreement; (vii) the absence of a material adverse effect on the other party since March 5, 2023; (viii) satisfaction of certain regulatory clearances; and (ix) certain contingent liabilities of TCR2 not exceeding $10 million. Certain conditions to the merger may not be satisfied or, if they are, the timing of such satisfaction is uncertain. If any conditions to the merger are not satisfied or, where waiver is permitted by applicable law, not waived, the merger will not be consummated. See the section of this joint proxy statement/prospectus titled “The Merger Agreement — Conditions to Completion of the Merger” for a discussion of the conditions to the merger.
If for any reason the merger is not completed or the closing of the merger is significantly delayed, the Adaptimmune ADS price and business and results of operations of Adaptimmune, TCR2, and/or the combined company may be adversely affected. In addition, failure to consummate the merger would prevent Adaptimmune shareholders from realizing the anticipated benefits of the merger. Adaptimmune and TCR2 have incurred, and expect to continue to incur, significant transaction fees, professional service fees, taxes and other costs related to the merger. Further, if the merger agreement is terminated, under certain circumstances, TCR2 or Adaptimmune would be required to pay a termination fee equal to $2.4 million.
Lawsuits may in the future be filed against Adaptimmune, TCR2 and members of their respective boards of directors challenging the merger, and an adverse ruling in any such lawsuit may delay or prevent the completion of the merger or result in an award of damages against Adaptimmune or TCR2.
Transactions such as the merger are frequently subject to litigation or other legal proceedings, including actions alleging that the Adaptimmune Board or TCR2 Board breached their respective fiduciary duties to their respective shareholders and stockholders by entering into the merger agreement, by failing to obtain a greater value in the transaction for their respective shareholders and stockholders, or otherwise. Neither Adaptimmune nor TCR2 can provide assurance that such litigation or other legal proceedings will not be brought. If litigation or other legal proceedings are in fact brought against Adaptimmune or TCR2, or against the Adaptimmune Board or TCR2 Board, they will defend against it, but might not be successful in doing so. An adverse outcome in such matters, as well as the costs and efforts of a defense even if successful, could have a material adverse effect on the business, results of operation or financial position of Adaptimmune, TCR2 or the combined company, including through the possible diversion of either company’s resources or distraction of key personnel.
 
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Furthermore, one of the conditions to the completion of the merger is the absence of an order, injunction, judgment, decree or ruling (whether temporary, preliminary or permanent) enacted, promulgated, issued or entered by any governmental authority of competent authority enjoining, restraining, preventing or prohibiting consummation of the merger. As such, if any plaintiffs are successful in obtaining an injunction preventing the consummation of the merger, that injunction may prevent the merger from becoming effective or from becoming effective within the expected time frame.
The directors and executive officers of TCR2 have interests in the merger that may be different from, or in addition to, those of other TCR2 stockholders, which could have influenced their decisions to support or approve the merger.
TCR2 stockholders should recognize that the directors and executive officers of TCR2 have interests in the merger that may be different from, or in addition to, their interests as stockholders of TCR2 generally. For TCR2 directors, and executives these interests may include the accelerated vesting and payment for certain TCR2 stock-based incentive awards as a result of the merger, as well as cash severance payments and benefits that may become payable in connection with the merger. TCR2’s directors and executive officers are also covered by certain indemnification and insurance arrangements. Following the close of the transaction, Garry Menzel (TCR2’s Chief Executive Officer) and two other directors of TCR2 are expected to join the board of directors of the surviving corporation. Such interests and benefits could have influenced the decisions of TCR2’s directors and executive officers to support or approve the merger. See the section of this joint proxy statement/prospectus “Interests of TCR2 Directors and Executive Officers in the Merger.
The merger agreement restricts Adaptimmune’s and TCR2’s ability to pursue alternatives to the merger, however, in specified circumstances, Adaptimmune or TCR2 may terminate the merger agreement to accept a superior proposal.
Under the merger agreement, Adaptimmune and TCR2 have agreed not to (1) take certain actions to solicit proposals relating to alternative business combination transactions or (2) subject to certain exceptions, including the receipt of a “parent superior proposal” or “company superior proposal” ​(as such terms are defined in the merger agreement), enter into discussions or an agreement concerning, or provide confidential information in connection with, any proposals for alternative business combination transactions. However, in specified circumstances, Adaptimmune or TCR2 may terminate the merger agreement to enter into a definitive agreement with respect to a “parent superior proposal” or “company superior proposal” prior to obtaining approval of the merger from its shareholders or stockholders, as applicable.
Upon termination of the merger agreement in specified circumstances, Adaptimmune or TCR2 would be required to pay a termination fee equal to $2.4 million. Following the payment of the termination fee, the paying party will, other than in certain circumstances, have no further obligation or liabilities to the other party. Such termination would deny Adaptimmune, TCR2, and their shareholders and stockholders, respectively, any benefits from the merger and could negatively impact Adaptimmune’s and/or TCR2’s market price.
These provisions could discourage a third party that may have an interest in acquiring all or a significant part of Adaptimmune or TCR2 from considering or proposing that acquisition, even if such third party were prepared to enter into a transaction that is more favorable to Adaptimmune or TCR2 or their respective shareholders and stockholders than the merger.
If the proposed merger is not completed, each of Adaptimmune and TCR2 will have incurred substantial costs that may adversely affect Adaptimmune’s and TCR2’s respective financial results.
Each of Adaptimmune and TCR2 have incurred and will continue to incur substantial costs in connection with the proposed merger. These costs are primarily associated with the fees of consultants, attorneys, accountants and financial advisors. In addition, each of Adaptimmune and TCR2 have diverted significant management resources in an effort to complete the merger and are subject to restrictions contained in the merger agreement on the conduct of their respective businesses during the pendency of the merger. If the merger is not completed, such costs may adversely affect Adaptimmune’s and TCR2’s financial results.
 
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Uncertainties associated with the merger may cause a loss of employees and may otherwise affect the future business and operations of Adaptimmune, TCR2 and the combined company.
Uncertainty about the effect of the merger on employees and customers may have an adverse effect on Adaptimmune or TCR2 and, if the proposed merger with TCR2 is consummated, on the combined company following the merger. These consequent uncertainties may impair Adaptimmune’s, TCR2’s and following the closing of the merger, the combined company’s, ability to retain and motivate key personnel and could also cause customers, suppliers, licensees, partners and others who deal with Adaptimmune or TCR2 to defer entering into contracts with, making other decisions concerning, or seeking to change existing business relationships with Adaptimmune or TCR2, and following the closing of the merger, the combined company. Because Adaptimmune and TCR2 depend on the experience and industry knowledge of their executives and other key personnel to execute their business plans, the combined company may be unable to meet its strategic objectives.
While the merger is pending, Adaptimmune and TCR2 may not be able to hire qualified personnel to replace any key employees that may depart to the same extent that they have been able to in the past. In addition, if the merger is not completed, Adaptimmune and TCR2 may also encounter challenges in hiring qualified personnel to replace key employees that may depart prior to the termination of the merger agreement.
Risks Related to the Combined Company Following the Merger
Adaptimmune and TCR2 may not successfully integrate.
If the merger is consummated, achieving the anticipated benefits of the proposed merger of Adaptimmune and TCR2 will depend in part upon whether the two companies integrate their businesses in an effective and efficient manner. Adaptimmune and TCR2 may not be able to accomplish this integration process successfully. The integration of businesses is complex and time-consuming. The difficulties that could be encountered include the following:

integrating personnel, operations and systems, while maintaining focus on selling and promoting existing and newly acquired or produced products;

coordinating geographically dispersed organizations;

distraction of management and employees from operations;

changes or conflicts in corporate culture;

management’s inability to manage a substantial increase in the number of employees;

management’s inability to train and integrate personnel, who may have limited experience with the respective companies’ business lines and products, and to deliver a consistent message regarding diseases treated by the combined company;

retaining existing customers and attracting new customers;

retaining existing employees and attracting new employees;

maintaining business relationships; and

inefficiencies associated with the integration and management of the operations of the combined company.
In addition, there will be integration costs and non-recurring transaction costs (such as fees paid to legal, financial, accounting and other advisors and other fees paid in connection with the merger) associated with the proposed merger, including costs associated with combining their operations and achieving the synergies Adaptimmune and TCR2 expect to obtain, and such costs may be significant.
An inability to realize the full extent of the anticipated benefits of the proposed merger of Adaptimmune and TCR2, including estimated cost synergies, as well as any delays encountered in the integration process and realizing such benefits, could have an adverse effect upon the revenues, level of expenses and operating results of the combined company, which may materially adversely affect the value of the Adaptimmune ADSs after the consummation of the merger.
 
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Future results of the combined company may differ materially from the unaudited pro forma condensed combined financial statements of Adaptimmune and TCR2 presented in this joint proxy statement/prospectus.
The future results of the combined company following the completion of the merger may be materially different from those shown in the Unaudited Pro Forma Condensed Combined Financial Statements presented in this joint proxy statement/prospectus, which show only a combination of Adaptimmune’s and TCR2’s standalone historical results after giving effect to the merger, subject to the matters noted therein. Adaptimmune and TCR2 estimated that they will record approximately $12.4 million in transaction expenses, as described in the notes to the Unaudited Pro Forma Condensed Combined Financial Statements included in this joint proxy statement/prospectus. In addition, the final amount of any charges relating to acquisition accounting adjustments that Adaptimmune may be required to record will not be known until following the completion of the merger. These and other expenses and charges may be significantly higher or lower than estimated.
Certain contractual counterparties may seek to modify contractual relationships with the combined company, which could have an adverse effect on the combined company’s business and operations.
As a result of the merger, the combined company may experience impacts on relationships with contractual counterparties (such as business partners, surgeons, vendors, sales representatives, contractors or other third-party service providers) that may harm the combined company’s business and results of operations. Certain counterparties may seek to terminate or modify contractual obligations following the merger whether or not contractual rights are triggered as a result of the merger. There can be no guarantee that Adaptimmune’s or TCR2’s contractual counterparties will remain with or continue to have a relationship with the combined company or do so on the same or similar contractual terms following the merger. If any contractual counterparties (such as business partners, surgeons, vendors, sales representatives, contractors or other third party service providers) seek to terminate or modify contractual obligations or discontinue the relationship with the combined company, then the combined company’s business and results of operations may be harmed.
The market price of Adaptimmune ADSs may be affected by factors different from those affecting the market price of shares of TCR2 Common Stock.
If the merger is consummated, TCR2 stockholders will become holders of Adaptimmune ADSs. Adaptimmune’s business differs from that of TCR2, and Adaptimmune’s results of operations, as well as the market price of Adaptimmune ADSs, may be affected by factors different from those affecting TCR2’s results of operations and the market price of shares of TCR2 Common Stock.
TCR2 stockholders who receive Adaptimmune ADSs in the merger will have rights as holders of Adaptimmune ADSs that differ from their current rights as TCR2 stockholders.
Upon completion of the merger, TCR2 stockholders will no longer be stockholders of TCR2 and will instead become holders of Adaptimmune ADSs. Holders of Adaptimmune ADSs will be able to exercise the shareholder rights for Adaptimmune ordinary shares represented by such Adaptimmune ADSs through the depositary bank, only to the extent contemplated by the deposit agreement. For more information, see the description of Adaptimmune ADSs contained in the Adaptimmune Annual Report on Form 10-K, filed on March 6, 2023, which is incorporated into this document by reference, as well as the section of this joint proxy statement/prospectus titled “Description of Adaptimmune ADSs” for a discussion of the terms of the Adaptimmune ADSs and the material rights of owners of Adaptimmune ADSs. There are certain differences in the rights of holders of Adaptimmune ADSs and of TCR2 stockholders under the TCR2 amended and restated certificate of incorporation (“TCR2 charter”) and TCR2 by-laws. See the section of this joint proxy statement/prospectus titled “Comparison of Holders’ Rights” for a discussion of these rights.
If the merger is consummated, current TCR2 stockholders will have a reduced ownership percentage and voting interest and will exercise less influence over the management and policies of the combined company than they do over TCR2.
In connection with the merger, each issued and outstanding share of TCR2 Common Stock will be converted into the right to receive the merger consideration representing approximately 25% of the combined
 
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company’s ordinary shares following the closing of the merger. Adaptimmune shareholders and TCR2 stockholders currently have the right to vote for their respective directors and on other matters affecting their respective companies. When the merger is consummated, each TCR2 stockholder who receives Adaptimmune ADSs in the merger will become a shareholder of the combined company with a percentage ownership of the combined company that will be smaller than the stockholder’s percentage ownership of TCR2. As a result of their reduced ownership percentages, current TCR2 stockholders will have less voting power in the combined company than they now have separately with respect to TCR2.
Other Risk Factors Related to Adaptimmune and TCR2
Adaptimmune’s and TCR2’s businesses are and will be subject to the risks described above. In addition, Adaptimmune and TCR2 are, and will continue to be, subject to the risks described in, as applicable, the Adaptimmune 10-K and the TCR2 10-K, as such risks may be updated or supplemented in each company’s subsequently filed Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, each of which are filed with the SEC and incorporated by reference in this joint proxy statement/prospectus. See the section of this joint proxy statement/prospectus titled “Where You Can Find More Information” beginning on page 214 of this joint proxy statement/prospectus.
 
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DESCRIPTION OF ADAPTIMMUNE AND MERGER SUB
Adaptimmune
Adaptimmune is a clinical-stage biopharmaceutical company focused on providing novel cell therapies to people with cancer. Adaptimmune is a leader in the development of T-cell therapies for solid tumors and has reported responses in multiple solid tumor indications. Adaptimmune’s principal executive offices are located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, United Kingdom, and its telephone number is (44) 1235 430000.
Merger Sub
Merger Sub was formed by Adaptimmune solely in contemplation of the merger, has not conducted any business and has no assets, liability or obligations of any nature other than as set forth in the merger agreement. By operation of the merger, CM Merger Sub, Inc. will be merged with and into TCR2, with TCR2 continuing as the surviving corporation and as a wholly-owned direct subsidiary of CM Intermediate. Upon completion of the merger, the separate existence of CM Merger Sub, Inc. will cease to exist. Merger Sub’s principal executive offices are located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, United Kingdom, and its telephone number is (44) 1235-430000.
 
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DESCRIPTION OF TCR2
TCR2 was originally incorporated under the name TCR2, Inc. on May 29, 2015 in the State of Delaware, and subsequently changed its name to TCR2 Therapeutics Inc. on November 14, 2016. TCR2 is a clinical-stage cell therapy company developing a pipeline of novel T cell therapies for cancer patients suffering from solid tumors by powering the T cell receptor (TCR) with its proprietary, first-in-class TCR Fusion Construct T cells (TRuC-T cells). Designed to overcome the limitations of current cell therapy modalities, TCR2’s TRuC-T cells, an HLA-independent T cell therapy platform, recognize and kill cancer cells by harnessing the entire TCR signaling complex, which TCR2 believes is essential for T cell therapies to be effective in patients with solid tumors.
TCR2’s lead TRuC-T cell targeting mesothelin-expressing solid tumors is gavocabtagene autoleucel (gavo-cel, formerly TC-210). TCR2 has completed the Phase 1 portion of its Phase 1/2 clinical trial for gavo-cel to treat patients with ovarian cancer, non-small cell lung cancer (NSCLC), malignant pleural/peritoneal mesothelioma or cholangiocarcinoma. TCR2 estimates the patient population for gavo-cel in the four indications which the clinical trial is exploring is up to 81,000 patients in the United States alone.

Based on the topline data readout presented on September 28, 2022 from patients in dose escalation in the Phase 1 portion of TCR2’s Phase 1/2 clinical trial as of the September 9, 2022 data cutoff, gavo-cel has demonstrated consistent clinical benefit, with 28 of 30 patients evaluable for efficacy experiencing tumor regression, clinical activity observed in all three mesothelin-expressing tumor types treated (i.e. ovarian cancer, mesothelioma and cholangiocarcinoma), and a 77% disease control rate (DCR).

TCR2 has observed a 22% Overall Response Rate (ORR) in patients infused with gavo-cel following lymphodepletion with six (four mesothelioma, two ovarian cancer) RECIST partial responses (PRs) by independent assessment. The ORR was 21% in mesothelioma and 29% in ovarian cancer by blinded independent central review (BICR).

The median overall survival (OS) for patients with MPM was 11.2 months, whereas the median progression-free survival (PFS) for patients with MPM was 5.6 months. The median OS for patients with ovarian cancer was 8.1 months, whereas the median PFS for patients with ovarian cancer was 5.8 months.

Based on TCR2’s mesothelin cutoff screening protocol (confirmed positive mesothelin expression on ≥50% of tumor cells that are 2+ and/or 3+ by immunohistochemistry), 48% of patients screened have been eligible to be enrolled in the clinical trial.

A maximum tolerated dose (MTD) was declared by the Safety Review Team (SRT) after all three patients treated at dose level 5 (DL5: 5x108 cells/m2 following lymphodepletion) experienced Grade ≥3 CRS. Below DL5, gavo-cel exhibited a manageable safety profile 4 on-target, off-tumor toxicities reported. In late December 2021, the SRT declared 1x108 cells/m2 following lymphodepletion as the recommended Phase 2 dose (RP2D).
TCR2 designed the Phase 2 portion of its Phase 1/2 clinical trial to assess gavo-cel in patients with ovarian cancer, NSCLC, malignant pleural/peritoneal mesothelioma or cholangiocarcinoma. In January 2023, TCR2 announced that it had narrowed the focus of its development of gavo-cel in combination with Opdivo® (nivolumab) and Yervoy® (ipilimumab) and are evaluating redosing strategies which it believes may increase the duration of benefit in patients with ovarian cancer. TCR2 believes that these plans will allow them to prioritize material investment in gavo-cel and durability data from the ovarian cancer cohort is expected in the second half of 2023.
TCR2’s next most advanced program is TC-510, its first enhanced TRuC-T cell targeting mesothelin-expressing solid tumors which incorporates a PD-1:CD28 chimeric switch receptor. In TCR2’s preclinical studies of TC-510, they observed functional improvements over gavo-cel including enhanced signaling, increased proliferation, reduced exhaustion and improved in vivo efficacy against tumors with high PD-L1 expression. Based on these preclinical studies, TCR2 believes they can improve on the efficacy of gavo-cel in specific hostile solid tumor microenvironment settings and potentially expand into new solid tumor indications. TCR2 is conducting the Phase 1 portion of the Phase 1/2 clinical trial with initial objective response data expected in the second half of 2023.
 
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TCR2 is a public company whose shares trade on the Nasdaq under the ticker symbol “TCRR.” TCR2’s principal executive offices are located at 100 Binney Street, Suite 710, Cambridge, Massachusetts 02142, and telephone number is (617) 949-5200.
Additional information about TCR2 can be found on its website at http://www.tcr2.com. The information contained in, or that can be accessed through, TCR2’s website is not intended to be incorporated into this joint proxy statement/prospectus. For additional information about TCR2, see the section entitled “Where You Can Find More Information.”
 
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INFORMATION ABOUT THE ADAPTIMMUNE GENERAL MEETING
Time, Place and Purpose of the Adaptimmune General Meeting
This joint proxy statement/prospectus is being furnished to Adaptimmune shareholders as part of the solicitation of proxies by the Adaptimmune Board for use at the Adaptimmune general meeting to be held [•] London time ([•] Eastern Time) on [•], 2023, at Adaptimmune’s corporate headquarters, located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, or at any postponement or adjournment thereof. At the Adaptimmune general meeting, Adaptimmune shareholders will be asked to (i) approve the Allotment Proposal and (ii) approve the Share Issuance Proposal.
Adaptimmune shareholders must approve the Allotment Proposal and the Share Issuance Proposal in order for the merger to occur. If Adaptimmune shareholders fail to approve the Allotment Proposal and the Share Issuance Proposal, the merger will not occur. A copy of the merger agreement, as amended, is attached as Annex A to this joint proxy statement/prospectus, which Adaptimmune encourages you to read carefully and in its entirety.
Action to be Taken by Holders of Adaptimmune Ordinary Shares
If you are a holder of Adaptimmune ADSs, please ignore this section and refer instead to the section below “—Holders of Adaptimmune ADSs.”
Holders of Adaptimmune ordinary shares that are planning to attend the Adaptimmune general meeting in person (or by way of corporate representative) should inform Morrow Sodali, Adaptimmune’s proxy solicitor.
Any holder of Adaptimmune ordinary shares that is unable to attend the Adaptimmune general meeting can still vote on the Allotment Proposal and the Share Issuance Proposal by appointing a proxy. A form of proxy for use at the Adaptimmune general meeting is enclosed or is being sent by email to holders of Adaptimmune ordinary shares that have opted to receive information by email. Holders of Adaptimmune ordinary shares are able to submit their proxy vote online at www.investorcentre.co.uk/eproxy (see instructions on form of proxy) to arrive by no later than [] London time ([] Eastern Time) on [], 2023.
Alternatively, holders of Adaptimmune ordinary shares that have received a printed form of proxy and prefer to return it by post are advised to complete and return the form of proxy in accordance with the instructions printed on it so as to arrive at Adaptimmune’s registrar, Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England as soon as possible but in any event by no later than [•] London time ([•] Eastern Time) on [•], 2023. CREST members may appoint a proxy by using the CREST electronic proxy appointment service. The return of a form of proxy or the electronic appointment of a proxy does not preclude any holder of Adaptimmune ordinary shares from attending and voting at the Adaptimmune general meeting if they so wish.
This joint proxy statement/prospectus, including the notice of the Adaptimmune general meeting and associated materials for the Adaptimmune general meeting are being sent or supplied to holders of Adaptimmune ordinary shares as of [•], 2023. In order to attend and vote at the Adaptimmune general meeting as a holder of Adaptimmune ordinary shares or for your form of proxy to remain valid, you must continue to be registered as a holder of ordinary shares in Adaptimmune’s register of members as of [•] London time ([•] Eastern Time) on [•], 2023.
Therefore, if any holder of Adaptimmune ordinary shares sells or transfers such Adaptimmune ordinary shares on or prior to [•], 2023, the form of proxy of such holder of Adaptimmune ordinary shares can no longer be used and if submitted (whether before or after you sell or transfer your Adaptimmune ordinary shares) will be treated as invalid. The selling or transferring holder of Adaptimmune ordinary shares should pass this document to the person who arranged the sale or transfer for delivery to the purchaser or transferee. The purchaser or transferee should contact Morrow Sodali, Adaptimmune’s proxy solicitor, to request a new form of proxy for its use.
Should a holder of Adaptimmune ordinary shares elect to convert their holding of Adaptimmune ordinary shares in the capital of Adaptimmune into an interest in the capital of Adaptimmune represented
 
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by ADSs before the Adaptimmune general meeting, such holder will cease to be a holder of Adaptimmune ordinary shares in their own name and will not be entitled to vote at the Adaptimmune general meeting as a holder of Adaptimmune ordinary shares. Such holder will also not be able to use the form of proxy that has been sent to them with this joint proxy statement/prospectus. However, such holder may be able to exercise their vote as a holder of an interest in the capital of Adaptimmune represented by Adaptimmune ADSs — please refer to the next section — “Holders of Adaptimmune ADSs.
Holders of Adaptimmune ADSs
In order to exercise their vote as a holder of Adaptimmune ADSs, the Adaptimmune ADS holder or their bank, broker or nominee must be registered as a holder of ADSs in the Adaptimmune ADS register by [•] p.m. Eastern Time on [•], 2023 (the record date for holders of Adaptimmune ADSs).
Any holder of Adaptimmune ADSs through a bank, broker or nominee on [•], 2023, will have the materials for holders of Adaptimmune ADSs, which include the depositary bank’s notice of the Adaptimmune general meeting, the Adaptimmune general meeting documentation, and Adaptimmune ADS proxy card, sent to their bank, broker or nominee who should forward the materials to them. Please reach out to your bank, broker or nominee to provide your voting instructions.
Please note that Adaptimmune ADS proxy cards submitted by holders of Adaptimmune ADSs must be received by the depositary bank by no later than [•] Eastern Time on [•], 2023.
Contact for Holders of Adaptimmune ADSs
If you have queries about how you can deliver voting instructions, please contact Citibank, N.A. — ADR Shareholder Services at tel: +1-877-248-4237 (toll free within the United States) or +1-781-575-4555 (for international callers) or by email: citibank@shareholders-online.com or at Citibank Shareholder Services, P.O. Box 43099, Providence, RI 02940-5000.
Contact at Adaptimmune
If at any point you have any queries, please contact Morrow Sodali, Adaptimmune’s proxy solicitor, by calling toll free at 1 (800) 662-5200. Banks, brokerage firms and other nominees may call collect at 1 (203) 658-9400.
Attendance
Attendance at the Adaptimmune general meeting will be limited to holders of record of Adaptimmune ordinary shares as of [•] London time ([•] Eastern Time) on [•]. In order to obtain admittance to the Adaptimmune general meeting each shareholder may be asked to present valid picture identification, such as a driver’s license or passport. Any registered holder of Adaptimmune ordinary shares may appoint a proxy to attend, speak and vote on his/her behalf.
Quorum
For the purposes of the Adaptimmune general meeting, a quorate meeting will be formed by two persons being present and between them holding (or being the proxy or corporative representative of the holders of) at least one-third in number of the issued Adaptimmune ordinary shares entitled to vote at the Adaptimmune general meeting.
If you are a holder of record of Adaptimmune ordinary shares, your shares will be counted towards the quorum only if you are present in person or represented by proxy at the Adaptimmune general meeting. If you are a beneficial owner of Adaptimmune ordinary shares held in an account at a brokerage firm, bank or other similar organization your shares will be counted towards the quorum if your broker or nominee submits a proxy for those shares and the proxy represents the holder at the Adaptimmune general meeting. A member represented by a proxy at the Adaptimmune general meeting will be counted towards the quorum requirement even where the proxy abstains from voting. If a form of proxy does not instruct the proxy how to vote, the proxy may vote as he or she sees fit or abstain in relation to any business of the Adaptimmune general meeting, but the member represented by that proxy at the Adaptimmune general meeting will be
 
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counted towards the quorum requirement. If there is no quorum, the Adaptimmune general meeting will stand adjourned to such time, date and place as may be fixed by the chairperson of the Adaptimmune general meeting (being not less than 10 days later), and, if a quorum is not present at the adjourned meeting, the Adaptimmune general meeting will be dissolved.
Where the depositary bank submits votes on behalf of any holders of Adaptimmune ADSs, the number of ordinary shares represented by the Adaptimmune ADSs held by the relevant holders of Adaptimmune ADSs will count towards the quorum.
Vote Required
The Allotment Proposal and the Share Issuance Proposal are being proposed as ordinary resolutions. Under English law, assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution.
You may vote “FOR,” “AGAINST” or “VOTE WITHHELD” for the Allotment Proposal and the Share Issuance Proposal. Votes withheld (or abstentions) and broker non-votes are not votes in law and will not be counted in the calculation of the votes “FOR” and “AGAINST” a resolution.
In accordance with the rules of Nasdaq, banks, brokerage firms or other nominees who hold Adaptimmune ADSs in “street name” for customers are precluded from exercising their voting discretion with respect to approving non-routine matters such as the adoption of the Allotment Proposal and the Share Issuance Proposal. Additionally, for Adaptimmune ordinary shares that are held in an account at a brokerage firm, bank or other similar organization, the shareholder of record is considered such brokerage firm, bank or other similar organization. As a result, absent specific instructions from the beneficial owner of such shares of Adaptimmune ordinary shares, banks, brokerage firms and other nominees are not empowered to vote those shares of Adaptimmune ordinary shares on non-routine matters. These broker non-votes will not be counted in respect of, and will not have any effect on, the Allotment Proposal and the Share Issuance Proposal.
With respect to Adaptimmune ADSs, if voting is by poll and the depositary bank does not receive voting instructions from a holder of Adaptimmune ADSs as of the record date for holders of Adaptimmune ADSs on or before the date established by the depositary bank for such purpose, such holder of Adaptimmune ADSs will be deemed, and the depositary bank will deem such holder, to have instructed the depositary bank to give a discretionary proxy to a person designated by Adaptimmune to vote the Adaptimmune ADSs; provided, however, that no such discretionary proxy will be given by the depositary bank with respect to any matter to be voted upon as to which Adaptimmune informs the depositary bank that (i) Adaptimmune does not wish such proxy to be given, (ii) substantial opposition exists, or (iii) the rights of holders of Adaptimmune ADSs may be adversely affected.
If you have any questions or need assistance voting your shares, please contact Morrow Sodali, Adaptimmune’s proxy solicitor, by calling toll-free at 1 (800) 662-5200. Banks, brokerage firms and other nominees may call collect at 1 (203) 658-9400.
IT IS IMPORTANT THAT YOU VOTE YOUR SHARES OF ADAPTIMMUNE ORDINARY SHARES AT THE ADAPTIMMUNE GENERAL MEETING PROMPTLY. WHETHER OR NOT YOU PLAN TO ATTEND THE ADAPTIMMUNE GENERAL MEETING, PLEASE COMPLETE, DATE, SIGN AND RETURN, AS PROMPTLY AS POSSIBLE, THE ENCLOSED PROXY CARD IN THE ACCOMPANYING PREPAID REPLY ENVELOPE, OR SUBMIT YOUR PROXY BY THE INTERNET. ADAPTIMMUNE SHAREHOLDERS WHO ATTEND THE ADAPTIMMUNE GENERAL MEETING MAY REVOKE THEIR PROXIES BY VOTING IN PERSON.
As of March 28, 2023, the directors and executive officers of Adaptimmune beneficially owned and were entitled to vote, in the aggregate, 13,027,948 Adaptimmune ordinary shares (not including any
 
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Adaptimmune ordinary shares deliverable upon the vesting of any restricted stock unit style options or the exercise of any options). This includes Adaptimmune ordinary shares which are represented by Adaptimmune ADSs.
Proxies and Revocation
A registered holder of Adaptimmune ordinary shares can revoke his or her proxy, whether delivered over the Internet or by mail, at any time before [•], London Time, on [•], 2023, by voting again through any of the methods available to you, by notifying Adaptimmune’s registrar, Computershare, in writing that you are revoking your proxy, which must be received by Computershare by not less than 48 hours (not including non-business days) before the time of the Adaptimmune general meeting to be effective, or by attending the Adaptimmune general meeting and voting in person. Written notice of revocation should be mailed to: Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, England.
If Adaptimmune ordinary shares are held in an account at a brokerage firm, bank or similar organization, voting instructions may be changed or revoked by contacting the broker, bank or other nominee holding the shares.
Adjournments
Although it is not currently expected, the Adaptimmune general meeting may be adjourned (with the consent of the meeting) for the purpose of soliciting additional proxies if there are insufficient votes at the time of the Adaptimmune general meeting to pass the resolutions to be proposed, and will be adjourned if a quorum is not present at the Adaptimmune general meeting. Any adjournment of the Adaptimmune general meeting for the purpose of soliciting additional proxies will allow Adaptimmune shareholders who have already sent in their proxies to revoke them prior to their use at the Adaptimmune general meeting as adjourned.
Anticipated Date of Completion of the Merger
Subject to the satisfaction or waiver of the closing conditions described under the section titled, “The Merger Agreement — Conditions to Completion of the Merger,” including the approval by Adaptimmune shareholders of the Allotment Proposal and the Share Issuance Proposal at the Adaptimmune general meeting, Adaptimmune and TCR2 expect that the merger will be completed in the second quarter of 2023. The merger agreement provides that the closing will occur as early as practicable on a date to be specified by the parties to the merger agreement and no later than the second business day after satisfaction or waiver of all of the conditions to closing described under the section titled, “The Merger Agreement — Conditions to Completion of the Merger,” other than those conditions that by their nature may only be satisfied at the closing, but subject to the satisfaction or waiver of such conditions at the closing. See the section of this joint proxy statement/prospectus titled, “The Merger — Closing and Effective Time of the Merger.
Solicitation of Proxies; Payment of Solicitation Expenses
Adaptimmune has engaged Morrow Sodali to assist in the solicitation of proxies for the Adaptimmune general meeting. Adaptimmune estimates that it will pay Morrow Sodali a fee not to exceed $15,000. Adaptimmune has agreed to reimburse Morrow Sodali for certain reasonable and documented out-of-pocket fees and expenses, including telephone charges, and also will indemnify Morrow Sodali, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses. Adaptimmune may also reimburse banks, brokers or their agents for their expenses in forwarding proxy materials to beneficial owners of Adaptimmune’s ordinary shares. Adaptimmune’s directors, officers and employees also may solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies. Adaptimmune also has agreed to reimburse the depositary bank for its expenses in sending materials, including Adaptimmune ADS proxy cards, to Adaptimmune ADS holders of record.
 
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Questions and Additional Information
If you are a holder of Adaptimmune ordinary shares or Adaptimmune ADSs and have additional questions about the merger, need assistance in submitting your form of proxy or voting your Adaptimmune ordinary shares or Adaptimmune ADSs, or need additional copies of this joint proxy statement/prospectus or the enclosed proxy card, please contact Morrow Sodali, Adaptimmune’s proxy solicitor, by calling toll-free at 1 (800) 662-5200. Banks, brokerage firms and other nominees may call collect at 1 (203) 658-9400.
 
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ADAPTIMMUNE PROPOSAL 1:
APPROVAL OF THE ALLOTMENT
This joint proxy statement/prospectus is being furnished to you as a Adaptimmune shareholder in connection with the solicitation of proxies by the Adaptimmune Board for use at the Adaptimmune general meeting. Under the Companies Act 2006, the Adaptimmune Board cannot allot Adaptimmune ordinary shares (other than pursuant to an employee share scheme) unless they are authorized to do so by Adaptimmune shareholders. At the Adaptimmune general meeting, Adaptimmune is asking Adaptimmune shareholders to consider and vote upon a proposal to authorize the Adaptimmune Board (or a duly authorized committee thereof) to allot new shares or to grant rights to subscribe for or to convert any security into Adaptimmune ordinary shares up to a maximum aggregate nominal amount of £[•] in connection with the merger (the “Allotment Proposal”).
Based on the number of shares of TCR2 Common Stock outstanding as of March 28, 2023, the latest practicable date prior to the date of this joint proxy statement/prospectus, Adaptimmune expects to issue approximately 62,491,891 Adaptimmune ADSs to TCR2 stockholders in connection with the merger. The actual number of Adaptimmune ADSs to be issued in connection with the merger will be based on the number of shares of TCR2 Common Stock outstanding at the Effective Time and the Exchange Ratio. Based on the number of shares of Adaptimmune ADSs and TCR2 Common Stock outstanding as of March 28, 2023, the latest practicable date prior to the date of this joint proxy statement/prospectus, upon completion of the merger, Adaptimmune shareholders immediately prior to the merger are expected to own approximately 75% of the combined company’s ordinary shares and TCR2 stockholders immediately prior to the merger are expected to own approximately 25% of the combined company’s ordinary shares.
The Adaptimmune Board has carefully considered and (i) unanimously determined that the terms of the merger and the other transactions contemplated by the merger agreement are most likely to promote the success of Adaptimmune for the benefit of Adaptimmune shareholders, (ii) unanimously approved, adopted and declared advisable the merger agreement and the transactions contemplated thereby, (iii) unanimously resolved, subject to Section 5.4(c) of the merger agreement, to recommend that Adaptimmune shareholders approve authorization of the Adaptimmune Board to allot all Adaptimmune ordinary shares to be issued in connection with the merger and (iv) directed that the issuance of Adaptimmune ordinary shares represented by Adaptimmune ADSs in connection with the merger be submitted to Adaptimmune shareholders for approval.
The Adaptimmune Board unanimously recommends that Adaptimmune shareholders vote “FOR” the Allotment Proposal.
The Allotment Proposal is being proposed as ordinary resolution. Under English law, assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution. Any shares not present or represented by proxy (including due to the failure of a holder of Adaptimmune ordinary shares who holds shares in “street name” through a bank, broker or other nominee to provide voting instructions with respect to any proposals at the Adaptimmune general meeting to such bank, broker or other nominee) will have no effect on the outcome of the Allotment Proposal, provided that a quorum is otherwise present. An abstention by any shares present or represented by proxy on the Allotment Proposal will not be counted as votes cast in favor or against the Allotment Proposal but will count for the purpose of determining whether a quorum is present. Broker non-votes, if any, will have no effect on the Allotment Proposal.
With respect to Adaptimmune ADSs, if voting is by poll and the depositary bank does not receive voting instructions from a holder of Adaptimmune ADSs as of the record date for holders of Adaptimmune ADSs on or before the date established by the depositary bank for such purpose, such holder of Adaptimmune ADSs will be deemed, and the depositary bank will deem such holder, to have instructed the depositary bank to give a discretionary proxy to a person designated by Adaptimmune to vote the Adaptimmune ADSs; provided, however, that no such discretionary proxy will be given by the depositary bank with respect to any matter to be voted upon as to which Adaptimmune informs the depositary bank that
 
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(i) Adaptimmune does not wish such proxy to be given, (ii) substantial opposition exists, or (iii) the rights of holders of Adaptimmune ADSs may be adversely affected.
THE ADAPTIMMUNE BOARD UNANIMOUSLY RECOMMENDS A VOTE “FOR” THE ALLOTMENT PROPOSAL.
 
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ADAPTIMMUNE PROPOSAL 2:
APPROVAL OF THE SHARE ISSUANCE
The Adaptimmune Board has carefully considered and unanimously approved the merger agreement and the transactions contemplated thereby, including the merger, and determined that the merger agreement and the transactions contemplated thereby, including the merger, would most likely promote the success of Adaptimmune for the benefit of Adaptimmune shareholders. Adaptimmune is asking Adaptimmune shareholders to consider and vote upon a proposal to approve the issuance of shares of Adaptimmune ordinary shares to be represented by Adaptimmune ADSs in connection with the merger for purposes of applicable Nasdaq rules (the “Share Issuance Proposal”).
The Adaptimmune Board unanimously recommends that Adaptimmune shareholders vote “FOR” the Share Issuance Proposal.
The Share Issuance Proposal is being proposed as ordinary resolution. Under English law, assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. If a poll is demanded, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution. Any shares not present or represented by proxy (including due to the failure of a holder of Adaptimmune ordinary shares who holds shares in “street name” through a bank, broker or other nominee to provide voting instructions with respect to any proposals at the Adaptimmune general meeting to such bank, broker or other nominee) will have no effect on the outcome of the Share Issuance Proposal, provided that a quorum is otherwise present. An abstention by any shares present or represented by proxy on the Share Issuance Proposal will not be counted as votes cast in favor or against the Share Issuance Proposal but will count for the purpose of determining whether a quorum is present. Broker non-votes, if any, will have no effect on the Share Issuance Proposal.
With respect to Adaptimmune ADSs, if voting is by poll and the depositary bank does not receive voting instructions from a holder of Adaptimmune ADSs as of the record date for holders of Adaptimmune ADSs on or before the date established by the depositary bank for such purpose, such holder of Adaptimmune ADSs will be deemed, and the depositary bank will deem such holder, to have instructed the depositary bank to give a discretionary proxy to a person designated by Adaptimmune to vote the Adaptimmune ADSs; provided, however, that no such discretionary proxy will be given by the depositary bank with respect to any matter to be voted upon as to which Adaptimmune informs the depositary bank that (i) Adaptimmune does not wish such proxy to be given, (ii) substantial opposition exists, or (iii) the rights of holders of Adaptimmune ADSs may be adversely affected.
THE ADAPTIMMUNE BOARD UNANIMOUSLY RECOMMENDS A VOTE “FOR” THE SHARE ISSUANCE PROPOSAL.
 
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INFORMATION ABOUT THE TCR2 SPECIAL MEETING
This joint proxy statement/prospectus is being provided to TCR2 stockholders in connection with the solicitation of proxies by the TCR2 Board for use at the TCR2 special meeting and at any adjournments or postponements of the TCR2 special meeting. TCR2 stockholders are encouraged to read the entire document carefully, including the annexes to and documents incorporated by reference into this document, for more detailed information regarding the merger agreement and the transactions contemplated by the merger agreement.
Date, Time and Place of the TCR2 Special Meeting
The TCR2 special meeting is scheduled to be held virtually via the Internet on [•], 2023, beginning at [•], Eastern Time, unless postponed to a later date.
TCR2 has elected to hold the TCR2 special meeting solely by means of remote communication (via the Internet). The TCR2 special meeting will be held solely via live webcast and there will not be a physical meeting location. You will be able to attend the TCR2 special meeting online and vote their shares electronically by visiting www.proxydocs.com/TCRR to register and entering the your control number included on your proxy card or on the instructions that accompanied your proxy materials (the “special meeting website”).
To be admitted to the TCR2 special meeting and vote your shares, you must register in advance at www.proxydocs.com/TCRR prior to the deadline of [•] at [•] Eastern Time. You will be required to enter the control number provided in the proxy card at www.proxydocs.com/TCRR and beneficial owners of shares held in street name will need to follow the instructions provided in the voting instructions form by the broker, bank or other nominee that holds their shares. Upon completing your registration, you will receive further instructions via email, including unique links to access the TCR2 special meeting and to submit questions in advance of the TCR2 special meeting.
TCR2 will entertain questions at the TCR2 special meeting in accordance with the rules of conduct for the meeting to the extent that the question posed by a stockholder are relevant to the TCR2 special meeting and the proposals presented. Any questions or comments that are unrelated to the business of the TCR2 special meeting will not be addressed at the meeting.
Matters to Be Considered at the TCR2 Special Meeting
The purpose of the TCR2 special meeting is to consider and vote on each of the following proposals, each of which is further described in this joint proxy statement/prospectus:

Proposal 1:   Adoption of the Merger Agreement.   To consider and vote on the merger proposal; and

Proposal 2:   Adjournment or Postponement of the TCR2 Special Meeting.   To consider and vote on the TCR2 adjournment proposal.
Recommendation of the TCR2 Board
The TCR2 Board recommends that TCR2 stockholders vote:

Proposal 1:   “FOR” the merger proposal; and

Proposal 2:   “FOR” the TCR2 adjournment proposal.
After careful consideration, the TCR2 Board (i) unanimously determined that terms the merger agreement and the other transactions contemplated by the merger agreement are advisable, fair to and in the best interests of TCR2 and its stockholders, (ii) unanimously approved, adopted and declared advisable the merger agreement and the transactions contemplated by the merger agreement, (iii) unanimously resolved, subject to Section 5.3(c) of the merger agreement, to recommended that the TCR2 stockholders adopt the merger agreement and the transactions contemplated by the merger agreement, and (iv) has directed that the merger agreement and the transactions contemplated by the merger agreement be submitted to the TCR2 stockholders for adoption.
 
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See also the section in this joint proxy statement/prospectus titled “The Merger — TCR2’s Reasons for the Merger; Recommendation of TCR2’s Board that TCR2 Stockholders Approve the Merger Proposal.”
Record Date for the TCR2 Special Meeting and Voting Rights
As of the close of business on the Record Date, there were [•] shares of TCR2 Common Stock issued and outstanding and entitled to vote at the TCR2 special meeting.
Each TCR2 stockholder is entitled to one vote for each share of TCR2 Common Stock such holder owned of record at the close of business on the record date with respect to each matter properly brought before the TCR2 special meeting. Only TCR2 stockholders of record at the close of business on the record date are entitled to receive notice of and to vote at the TCR2 special meeting and any and all adjournments or postponements thereof.
Quorum; Abstentions and Broker Non-Votes
A quorum of TCR2 stockholders is necessary to conduct the TCR2 special meeting. The presence, via the TCR2 special meeting website or by proxy, of the holders of a majority of the shares of TCR2 Common Stock entitled to vote at the TCR2 special meeting will constitute a quorum. Shares of TCR2 Common Stock represented at the TCR2 special meeting by attendance via the special meeting website or by proxy and entitled to vote, but not voted, including shares for which a stockholder directs an “abstention” from voting, will be counted for purposes of determining a quorum. However, because all of the proposals for consideration at the TCR2 special meeting are considered “non-routine” matters under the New York Stock Exchange Rules which also apply to Nasdaq listed companies (as described below), shares held in “street name” will not be counted as present for the purpose of determining the existence of a quorum unless the stockholder provides their bank, broker or other nominee with voting instructions for at least one of the proposals before the TCR2 special meeting. If a quorum is not present, the TCR2 special meeting will be adjourned or postponed until the holders of the number of shares of TCR2 Common Stock required to constitute a quorum attend.
Under the New York Stock Exchange rules, banks, brokers or other nominees who hold shares in “street name” on behalf of the beneficial owner of such shares have the authority to vote such shares in their discretion on certain “routine” proposals when they have not received voting instructions from the beneficial owners. However, banks, brokers or other nominees are not allowed to exercise their voting discretion with respect to matters that under the Nasdaq rules, as applicable, are “non-routine.” This can result in a “broker non-vote,” which occurs on an item when (1) a bank, broker or other nominee has discretionary authority to vote on one or more “routine” proposals to be voted on at a meeting of stockholders, but is not permitted to vote on other “non-routine” proposals without instructions from the beneficial owner of the shares and (2) the beneficial owner fails to provide the bank, broker or other nominee with voting instructions on a “non-routine” matter. All of the proposals before the TCR2 special meeting are considered “non-routine” matters under the Nasdaq rules, and banks, brokers or other nominees will not have discretionary authority to vote on any matter before the meeting. As a result, TCR2 does not expect any broker non-votes at the TCR2 special meeting and if you hold your shares of TCR2 Common Stock in “street name,” your shares will not be represented and will not be voted on any matter unless you affirmatively instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instructions provided by your bank, broker or other nominee. It is therefore critical that you cast your vote by instructing your bank, broker or other nominee on how to vote. Brokers will not be able to vote on any of the proposals before the TCR2 special meeting unless they have received voting instructions from the beneficial owners.
Required Votes
Except for the TCR2 adjournment proposal, the vote required to approve each of the proposals listed below assumes the presence of a quorum at the TCR2 special meeting. As described above, TCR2 does not expect there to be any broker non-votes at the TCR2 special meeting.
 
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Proposal
Required Vote
Effect of Certain Actions
Proposal 1:
Merger Proposal
Approval requires the affirmative vote of at least a majority of the outstanding shares of TCR2 Common Stock entitled to vote on the merger proposal. Shares of TCR2 Common Stock not present at the TCR2 special meeting, shares that are present and not voted on the merger proposal, including due to the failure of any TCR2 stockholder who holds their shares in “street name” through a bank, broker or other nominee to give voting instructions to such bank, broker or other nominee with respect to the merger proposal, and abstentions will have the same effect as a vote “AGAINST” the merger proposal.
Proposal 2:
TCR2 Adjournment Proposal
Approval requires the affirmative vote of at least a majority of votes properly cast on the TCR2 adjournment proposal (meaning the number of votes cast “FOR” this proposal must exceed the votes cast “AGAINST”). A vote to abstain, failure to vote or a broker non-vote will have no effect on the outcome of the TCR2 adjournment proposal.
Vote of TCR2’s Directors and Executive Officers
As of March 28, 2023 the latest practicable date prior to the date of this joint proxy statement/prospectus, TCR2 directors and executive officers, and their affiliates, as a group, owned and were entitled to vote in the aggregate 8,008,473 shares of TCR2 Common Stock, which represents approximately 20.41% of the shares of TCR2 Common Stock entitled to vote at the TCR2 special meeting. Certain of the TCR2 directors and executive officers have entered into voting and support agreements agreeing to, among other things, vote their shares in favor of the merger proposal, in accordance with the recommendation of the TCR2 Board. TCR2 currently expects that all of its directors and executive officers will vote their shares “FOR” the merger proposal and “FOR” the TCR2 adjournment proposal. See the TCR2 10-K filed with the SEC on March 23, 2023, which is incorporated into this joint proxy statement/prospectus by reference.
Methods of Voting
Registered Stockholders
If you are a stockholder of record, you may vote at the TCR2 special meeting by proxy through the Internet, by telephone or by mail, or by attending the TCR2 special meeting and voting via the special meeting website, as described below.

By Internet:   By visiting the Internet address provided on the proxy card and following the instructions provided on your proxy card.

By Telephone:   By calling the number located on the proxy card and following the recorded instructions.

By Mail:   If you have received a paper copy of the proxy materials by mail, you may complete, sign, date and return by mail the enclosed proxy card in the envelope provided to you with your proxy materials.

Via the Special Meeting Website:   All stockholders of record may vote at the TCR2 special meeting by attending the meeting via the special meeting website. You may vote your shares online while virtually attending the TCR2 special meeting by following instructions found on your proxy card and/or voting instruction form and subsequent instructions that will be delivered to you via email. If
 
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you vote by proxy prior to the TCR2 special meeting and choose to attend the TCR2 special meeting online, there is no need to vote again during the TCR2 special meeting unless you wish to change your vote.
Unless revoked, all duly executed proxies representing shares of TCR2 Common Stock entitled to vote will be voted at the TCR2 special meeting and, where a choice has been specified on the proxy card, will be voted in accordance with such specification. If you submit an executed proxy without providing instructions with respect to any proposal, then the TCR2 officers identified on the proxy will vote your shares consistent with the recommendation of the TCR2 Board on such proposal. If you are a TCR2 stockholder of record, proxies submitted over the Internet or by telephone as described above must be received by 11:59 p.m., Eastern Time, on [•], 2023. To reduce administrative costs and help the environment by conserving natural resources, TCR2 asks that you vote through the Internet or by telephone.
By executing and delivering a proxy in connection with the TCR2 special meeting, you designate certain TCR2 officers identified therein as your proxies at the TCR2 special meeting. If you deliver an executed proxy, but do not specify a choice with respect to any proposal properly brought before the TCR2 special meeting, such proxies will vote your underlying shares of TCR2 Common Stock on such uninstructed proposal in accordance with the recommendation of the TCR2 Board. TCR2 does not expect that any matter other than the proposals listed above will be brought before the TCR2 special meeting and the TCR2 by-laws provide that the only business that may be conducted at the TCR2 special meeting are those proposals brought before the meeting by or at the direction of the TCR2 Board.
Beneficial (Street Name) Stockholders
If you hold your shares through a bank, broker or other nominee in “street name” ​(instead of as a registered holder), you must follow the voting instructions provided by your bank, broker or other nominee in order to vote your shares. Your voting instructions must be received by your bank, broker or other nominee prior to the deadline set forth in the information from your bank, broker or other nominee on how to submit voting instructions. If you do not provide voting instructions to your bank, broker or other nominee with respect to a proposal, your shares of TCR2 Common Stock will not be voted on that proposal as your bank, broker or other nominee does not have discretionary authority to vote on any of the proposals to be voted on at the TCR2 special meeting; see the section of this joint proxy statement/prospectus titled “Information About the TCR2 Special Meeting — Quorum; Abstentions and Broker Non-Votes.”
If you hold your shares through a bank, broker or other nominee in “street name” ​(instead of as a registered holder), you must obtain a specific control number from your bank, broker or other nominee in order to attend and vote at the TCR2 special meeting via the special meeting website. For more information on how to attend the TCR2 special meeting, see the section of this joint proxy statement/prospectus titled “Information About the TCR2 Special Meeting — Attending the TCR2 Special Meeting.”
Revocability of Proxies
Any stockholder giving a proxy has the right to revoke it at any time before the proxy is voted at the TCR2 special meeting. If you are a TCR2 stockholder of record, you may revoke your proxy by any of the following actions:

by voting again by Internet or telephone as instructed on your proxy card before the closing of the voting facilities at 11:59 p.m., Eastern Time, on [•], 2023;

by sending a signed written notice of revocation to TCR2’s Corporate Secretary, provided such statement is received before the TCR2 special meeting;

by submitting a properly signed and dated proxy card as instructed above in advance of the TCR2 special meeting; or

by attending the TCR2 special meeting via the special meeting website and requesting that your proxy be revoked or voting via the website as described above.
Only your last submitted proxy card will be considered.
 
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Execution or revocation of a proxy will not in any way affect a TCR2 stockholder’s right to attend the TCR2 special meeting and vote thereat.
Written notices of revocation and other communications with respect to the revocation of proxies should be addressed to:
TCR2 Therapeutics Inc.
100 Binney Street, Suite 710
Cambridge, MA 02142
Attn: Corporate Secretary
If your shares are held in “street name” and you previously provided voting instructions to your broker, bank or other nominee, you should follow the instructions provided by your broker, bank or other nominee to revoke or change your voting instructions. You may also change your vote by obtaining your specific control number and instructions from your bank, broker or other nominee and voting your shares at the TCR2 special meeting via the special meeting website.
Proxy Solicitation Costs
TCR2 is soliciting proxies to provide an opportunity to all TCR2 stockholders to vote on agenda items at the TCR2 special meeting, whether or not the stockholders are able to attend the TCR2 special meeting or any adjournment or postponement thereof. TCR2 will bear the entire cost of soliciting proxies from its stockholders. In addition to the solicitation of proxies by mail, TCR2 will request that banks, brokers and other nominee record holders send proxies and proxy material to the beneficial owners of shares of TCR2 Common Stock and secure their voting instructions, if necessary. TCR2 may be required to reimburse those banks, brokers and other nominees on request for their reasonable expenses in taking those actions.
TCR2 has also retained Innisfree to assist in soliciting proxies and in communicating with TCR2 stockholders and estimates that it will pay them a fee of approximately $100,000 plus reasonable expenses. TCR2 has also agreed to indemnify Innisfree against certain losses, damages and expenses. Proxies may be solicited on behalf of TCR2 or by TCR2’s directors, officers and other employees in person, by mail, by telephone, by facsimile, by messenger, via the Internet or by other means of communication, including electronic communication. Directors, officers and employees of TCR2 will not be paid any additional amounts for their services or solicitation in this regard.
Attending the TCR2 Special Meeting
If you wish to attend the TCR2 special meeting via the special meeting website, you must (i) be a stockholder of record of TCR2 at the close of business on the Record Date, (ii) hold your shares of TCR2 beneficially in the name of a broker, bank or other nominee as of the Record Date or (iii) hold a valid proxy for the TCR2 special meeting.
To enter the special meeting website and attend the TCR2 special meeting, you must register in advance at www.proxydocs.com/TCRR prior to the deadline of [•], 2023 at [•] p.m., Eastern Time. If you hold your shares of TCR2 Common Stock in street name beneficially through a broker, bank or other nominee and you wish to attend the TCR2 special meeting via the special meeting website, you will need to obtain your specific control number and further instructions from your bank, broker or other nominee.
If you plan to attend the TCR2 special meeting and vote via the special meeting website, TCR2 still encourages you to vote in advance by the Internet, telephone or (if you received a paper copy of the proxy materials) by mail so that your vote will be counted in the event you later decide not to attend the TCR2 special meeting via the special meeting website. Voting your proxy by the Internet, telephone or mail will not limit your right to vote at the TCR2 special meeting via the special meeting website if you later decide to attend the TCR2 special meeting.
Householding
The SEC has adopted rules that permit companies and intermediaries such as brokers to satisfy delivery requirements for proxy statements with respect to two or more stockholders sharing the same
 
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address by delivering a single proxy statement addressed to those stockholders. This process, which is commonly referred to as “householding,” potentially provides extra convenience for stockholders and cost savings for companies. TCR2 and some brokers “household” proxy materials, delivering a single proxy statement to multiple stockholders sharing an address unless contrary instructions have been received from the affected stockholders. Once you have received notice from your broker or TCR2 that they or TCR2 will be householding materials to your address, householding will continue until you are notified otherwise or until you revoke your consent. If, at any time, you no longer wish to participate in householding and would prefer to receive a separate proxy statement, or if you are receiving multiple copies of the proxy statement and wish to receive only one, please notify your broker if your shares are held in a brokerage account, or TCR2 if you hold shares directly in your name. You can notify TCR2 by sending a written request to TCR2 Therapeutics Inc., 100 Binney Street, Suite 710, Cambridge, MA 02124, Attention: Corporate Secretary.
Tabulation of Votes
The TCR2 Board will appoint an independent inspector of election for the TCR2 special meeting. The inspector of election will, among other matters, determine the number of shares of TCR2 Common Stock represented at the TCR2 special meeting to confirm the existence of a quorum, determine the validity of all proxies and ballots and certify the results of voting on all proposals submitted to TCR2 stockholders at the TCR2 special meeting.
Adjournments
If a quorum is present at the TCR2 special meeting but there are not sufficient votes at the time of the TCR2 special meeting to approve the merger proposal, then TCR2 stockholders may be asked to vote on the TCR2 adjournment proposal.
At any subsequent reconvening of the TCR2 special meeting at which a quorum is present, any business may be transacted that might have been transacted at the original meeting and all proxies will be voted in the same manner as they would have been voted at the original convening of the TCR2 special meeting, except for any proxies that have been effectively revoked or withdrawn prior to the time the proxy is voted at the reconvened meeting.
Assistance
If you need assistance voting or in completing your proxy card or have questions regarding the TCR2 special meeting, please contact Innisfree, TCR2’s proxy solicitor for the TCR2 special meeting:
Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Stockholders may call toll free: 1 (877) 750-8233
Banks and Brokers may call collect: 1 (212) 750-5833
TCR2 STOCKHOLDERS SHOULD CAREFULLY READ THIS JOINT PROXY STATEMENT/PROSPECTUS IN ITS ENTIRETY FOR MORE DETAILED INFORMATION CONCERNING THE MERGER AGREEMENT AND THE MERGER. IN PARTICULAR, TCR2 STOCKHOLDERS ARE DIRECTED TO THE MERGER AGREEMENT, AS AMENDED, WHICH IS ATTACHED AS ANNEX A HERETO.
 
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TCR2 PROPOSAL NO 1: ADOPTION OF THE MERGER AGREEMENT
General
This joint proxy statement/prospectus is being provided to the holders of shares of TCR2 Common Stock in connection with the solicitation of proxies by the TCR2 Board to be voted at the TCR2 special meeting and at any adjournments or postponements of the TCR2 special meeting. At the TCR2 special meeting, TCR2 will ask its stockholders to vote on (i) the merger proposal and (ii) the TCR2 adjournment proposal.
The merger agreement provides for the merger of Merger Sub with and into TCR2, with TCR2 continuing as the surviving corporation and wholly-owned subsidiary of Adaptimmune. The merger will not be completed and the merger consideration will not be issued unless the TCR2 stockholders approve the merger proposal and the Adaptimmune shareholders approve the issuance of the merger consideration, and the other closing conditions specified in the merger agreement are met or waived.
A copy of the merger agreement, as amended, is attached as Annex A to this joint proxy statement/prospectus. You are urged to read the merger agreement in its entirety because it is the legal document that governs the merger. For additional information about the merger and the merger agreement, see the sections of this joint proxy statement/prospectus titled “The Merger” and “The Merger Agreement.”
The TCR2 Board, after careful consideration, has (i) unanimously determined that the merger and the transactions contemplated in the merger agreement are advisable, fair to and in the best interests of, TCR2 and the TCR2 stockholders, (ii) unanimously approved, adopted and declared advisable the merger agreement and the transactions contemplated thereby, (iii) unanimously resolved to recommend that the TCR2 stockholders adopt the merger agreement and the transactions contemplated therein and (iv) directed that the merger agreement and the transactions contemplated therein be submitted to the TCR2 stockholders for adoption.
Vote Required
Approval of the merger proposal requires the affirmative vote of the holders of a majority of the outstanding shares of TCR2 Common Stock entitled to vote on this proposal. This proposal is a “non-discretionary” matter. Accordingly, a TCR2 stockholder’s abstention from voting on this proposal and broker non-votes will have the same effect as a vote “AGAINST” this proposal.
Unless marked otherwise, proxies received by TCR2 stockholders will be votes “FOR” the approval of the merger agreement.
Recommendation
THE TCR2 BOARD RECOMMENDS THAT THE TCR2 STOCKHOLDERS VOTE “FOR” THE MERGER PROPOSAL.
 
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TCR2 PROPOSAL NO. 2: ADJOURNMENT OR POSTPONEMENT OF THE TCR2 SPECIAL MEETING
TCR2 stockholders are being asked to consider and vote on a proposal to approve the adjournment or postponement of the TCR2 special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes at the time of the TCR2 special meeting to approve the merger proposal or to ensure that any supplement or amendment to this joint proxy statement/prospectus is timely provided to TCR2 stockholders. Any determination of whether it is necessary to adjourn or postpone the TCR2 special meeting (or any adjournment or postponement thereof) to solicit additional proxies will be made solely by TCR2 consistent with the terms of the merger agreement or with the consent of Adaptimmune.
Vote Required
Whether or not a quorum is present, the approval of the TCR2 adjournment proposal requires the affirmative vote of a majority of the votes properly cast at the TCR2 special meeting by holders of shares of TCR2 Common Stock. For purposes of the TCR2 adjournment proposal, “votes properly cast” on the proposal consist of votes “FOR” or “AGAINST” the proposal. Accordingly, a TCR2 stockholder’s abstention from voting on the TCR2 adjournment proposal will have no effect on the approval of the proposal. This proposal is considered a “discretionary matter.” Therefore, a broker may vote shares of TCR2 Common Stock held in “street name” without receiving explicit voting instructions from the beneficial owners of such shares and broker non-votes are not expected on this proposal.
Unless marked otherwise, proxies received by TCR2 stockholders will be votes “FOR” the approval of the TCR2 adjournment proposal.
Recommendation of the TCR2 Board
THE TCR2 BOARD RECOMMENDS THAT TCR2 STOCKHOLDERS VOTE “FOR” THE TCR2 ADJOURNMENT PROPOSAL.
 
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THE MERGER
The following is a description of the material aspects of the merger. The description may not contain all of the information that may be important to you. The discussion of the merger in this joint proxy statement/prospectus is qualified in its entirety by reference to the merger agreement, as amended, which is attached to this joint proxy statement/prospectus as Annex A and incorporated by reference into this joint proxy statement/prospectus. The representations, warranties and covenants contained in the merger agreement were made only for the purposes of the merger agreement and as of specified dates, were solely for the benefit of the parties to the merger agreement and may be subject to limitations agreed upon by the contracting parties and may be subject to standards of materiality applicable to the contracting parties. In addition, the assertions embodied in the representations and warranties contained in the merger agreement are qualified by information in a confidential disclosure letter that the parties have exchanged, which has been omitted pursuant to Item 601(b)(2) of Regulation S-K. Accordingly, you should not rely on the representations and warranties as characterizations of the actual state of affairs of Adaptimmune or TCR2.
You are encouraged to read carefully the entirety of this joint proxy statement/prospectus, including the merger agreement, for a more complete understanding of the merger.
General
Adaptimmune, Merger Sub and TCR2 have entered into the merger agreement, pursuant to which Merger Sub will be merged with and into TCR2, with TCR2 continuing as the surviving corporation and as a wholly-owned subsidiary of Adaptimmune. If the merger is completed, TCR2 Common Stock will be delisted from Nasdaq and deregistered under the Exchange Act, following which TCR2 will no longer be required to file periodic reports with the SEC with respect to TCR2 Common Stock.
The Parties to the Merger
Adaptimmune
Adaptimmune is a clinical-stage biopharmaceutical company focused on providing novel cell therapies to people with cancer. Adaptimmune is a leader in the development of T-cell therapies for solid tumors and has reported responses in multiple solid tumor indications. Adaptimmune’s principal executive offices are located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, United Kingdom, and its telephone number is (44) 1235 430000.
Merger Sub
Merger Sub was formed by Adaptimmune solely in contemplation of the merger, has not conducted any business and has no assets, liability or obligations of any nature other than as set forth in the merger agreement. By operation of the merger, CM Merger Sub, Inc. will be merged with and into TCR2, with TCR2 continuing as the surviving corporation and as a wholly-owned subsidiary of Adaptimmune. Upon completion of the merger, the separate existence of CM Merger Sub, Inc. will cease to exist. Merger Sub’s principal executive offices are located at 60 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RX, United Kingdom, and its telephone number is (44) 1235-430000.
TCR2
TCR2 is a clinical-stage cell therapy company developing a pipeline of novel T cell therapies for cancer patients suffering from solid tumors by powering the T cell receptor (TCR) with their proprietary, first-in-class TCR Fusion Construct T cells (TRuC-T cells). Designed to overcome the limitations of current cell therapy modalities, TCR2’s TRuC-T cells specifically recognize and kill cancer cells by harnessing the entire TCR signaling complex, independent of human leukocyte antigens (HLA), which TCR2 believes is essential for T cell therapies to be effective in patients with solid tumors. TCR2’s principal executive offices are located at 100 Binney Street, Suite 710, Cambridge, Massachusetts 02142, and its telephone number is (617) 949-5200.
 
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Merger Consideration
If the merger is completed, each issued and outstanding share of TCR2 Common Stock (other than shares of TCR2 Common Stock held by TCR2 as treasury stock, or shares of TCR2 Common Stock owned by Adaptimmune, Merger Sub or any direct or indirect wholly-owned subsidiaries of Adaptimmune), including shares of TCR2 Common Stock underlying TCR2 restricted stock units that immediately vest upon a change of control of TCR2, shall be converted into the right to receive the merger consideration; provided, that after taking into account all book-entry shares delivered by or on behalf of any holder, the number of Adaptimmune ADSs issued to such holder shall be rounded down to the nearest whole Adaptimmune ADS and no fractional Adaptimmune ADS shall be issued. Each Adaptimmune ADS represents six Adaptimmune ordinary shares.
Based on the closing price of Adaptimmune ADSs on Nasdaq of $1.06 on March 28, 2023, the latest practicable trading day prior to the date of this joint proxy statement/prospectus, the implied value of the consideration payable to TCR2 stockholders in the merger was approximately $1.60 per share of TCR2 Common Stock. The market price of shares of Adaptimmune ADSs that TCR2 stockholders receive at the time the merger is completed could be greater than, less than or the same as the market price of shares of Adaptimmune ADSs on the date of this joint proxy statement/prospectus or on the date of the Adaptimmune general meeting or TCR2 special meeting. Accordingly, you should obtain current market quotations for Adaptimmune ADSs and TCR2 Common Stock before deciding how to vote on the proposals hereto. Adaptimmune ADSs and shares of TCR2 Common Stock are traded on Nasdaq, under the symbols “ADAP” and “TCRR,” respectively. Shares of Adaptimmune ADSs will continue trading on Nasdaq under the symbol “ADAP” after completion of the merger.
Background of the Merger
Adaptimmune management and the Adaptimmune Board regularly evaluate the strategic opportunities available to Adaptimmune with a view towards strengthening Adaptimmune’s business, performance, industry positions and prospects and enhancing shareholder value. As part of its ongoing evaluation, Adaptimmune utilizes third parties to review the applicable landscape and potential options and evaluates and considers from time-to-time various potential strategic transactions, including potential mergers with or acquisitions of other participants in the biotech industry. Taken together with the current market position within the biotechnology sector, Adaptimmune management and the Adaptimmune Board have increasingly focused on strategies for ensuring longer term financial security and cash runway for Adaptimmune. From time-to-time, members of Adaptimmune management have met with TCR2 senior management to discuss the cell therapy industry as well as Adaptimmune’s and TCR2’s respective businesses.
TCR2 senior management and the TCR2 Board regularly review TCR2’s performance and prospects in light of its own business activities and external developments in the biotechnology and biopharmaceutical industries. From time to time, these reviews have included consideration of potential partnerships, collaborations and other strategic transactions such as acquisitions or divestitures of programs or technology to enhance stockholder value. TCR2 senior management provided periodic updates on its activities, including those described below, to the TCR2 Board.
During the first half of 2022, the TCR2 Board discussed the strategic, financial and operational challenges of operating TCR2’s business in the then-current environment, including the macro-economic, industry and market conditions negatively impacting clinical-stage cell therapy companies such as TCR2. The TCR2 Board discussed the need for significant capital investment to complete TCR2’s clinical trials of gavocabtagene autoleucel (gavo-cel, formerly TC-210) (“gavo-cel”) and TC-510, support the filing of an Investigational New Drug Application for TC-520, fund its manufacturing network, fund its innovative research and development efforts, hire the appropriate personnel necessary to execute on those priorities, retain critical talent, and operate generally as a public company, as well as the risks and uncertainties associated with conducting clinical trials for gavo-cel, pursuing related regulatory approvals and, if successful, launching and commercializing gavo-cel. The TCR2 Board discussed the risks and uncertainties associated with the competition for (or the availability of) patients for clinical trials for gavo-cel, the complexities of manufacturing and administering the TRuC-T cell therapy, the need to treat a sufficient number of patients to demonstrate a consistently durable response rate and survival benefit, and the need to build sufficient manufacturing capacity if the therapy is approved by the FDA. The TCR2 Board also discussed
 
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the risks and uncertainties associated with TCR2’s cash requirements, which had severely negatively impacted TCR2’s stock price and its ability to raise sufficient capital through equity financings. The TCR2 Board further discussed TCR2’s current cash position, its near-term priorities and related cash requirements, and the lack of attractive financing alternatives given then-current market conditions.
On March 24 and 25, 2022, the TCR2 Board held a regularly scheduled meeting at which members of TCR2 senior management and representatives of Goodwin Procter LLP (“Goodwin”), TCR2’s outside legal counsel, were present. At this meeting, TCR2 senior management provided a business update to the TCR2 Board. The TCR2 Board discussed the risks and challenges facing TCR2 mentioned above and considered the prolonged pressure on the stock prices of biopharmaceutical companies and the likelihood that, if the current economic environment were to continue, consolidation would occur in the biopharmaceutical industry, particularly in the capital intensive cell therapy sector in which TCR2 operates. Following discussion, the TCR2 Board determined that it would be in the best interests of TCR2 and the TCR2 stockholders for TCR2 to proactively review potential strategic transactions available to it in order to be a first mover in such consolidation among cell therapy companies. In this connection, the TCR2 Board discussed an unsolicited inbound call that one of the TCR2 directors had recently received from a privately-held cell therapy company (“Party A”) expressing interest in exploring a potential business combination transaction with TCR2. Following discussion, the TCR2 Board authorized TCR2 senior management to engage in discussions with Party A regarding a potential business combination transaction.
Beginning in late March 2022, as authorized by the TCR2 Board, TCR2 senior management engaged in discussions with Party A regarding a potential business combination transaction. In order to facilitate these discussions, TCR2 and Party A entered into a mutual confidentiality agreement, effective as of April 8, 2022. This mutual confidentiality agreement did not contain a standstill obligation.
On May 4, 2022, the TCR2 Board held a regularly scheduled meeting at which members of TCR2 senior management and representatives of Goodwin were present. At this meeting, TCR2 senior management provided a business update to the TCR2 Board. The TCR2 Board also discussed the risks and challenges facing TCR2 as a result of then-current macro-economic, industry and market conditions, its then-current cash position, the need for meaningful capital investment to advance TCR2’s product candidates, and the lack of attractive financing alternatives at that time. The TCR2 Board also discussed plans then being implemented to reduce costs to preserve available cash, as presented by TCR2 senior management at this meeting. TCR2 senior management also provided an update on the discussions with Party A. In light of the discussions at this meeting and previous TCR2 Board meetings, the TCR2 Board directed TCR2 senior management to engage an independent strategic consultant and conduct a strategic review, primarily focused on a potential acquisition of a relatively smaller sized cell therapy company as a way for TCR2 to become a consolidator in the cell therapy sector.
During June and July 2022, TCR2 senior management, in consultation with the independent strategic consultant, conducted the strategic review of potential acquisition candidates, as directed by the TCR2 Board. Also during this time period, TCR2 continued discussions and due diligence with Party A regarding a potential business combination transaction.
On July 28, 2022, the TCR2 Board held a regularly scheduled meeting at which members of TCR2 senior management and representatives of Goodwin were present. TCR2 senior management provided a business update to the TCR2 Board. TCR2 senior management also provided an update on the results of the strategic review conducted in consultation with the independent consultant and the discussions with Party A. The TCR2 Board discussed the risks and challenges facing TCR2 and whether TCR2 had the financial capacity to be positioned as a consolidator in the cell therapy sector. Following discussion, the TCR2 Board authorized TCR2 senior management to continue discussions with Party A as the other potential acquisition candidates identified in the strategic review presented to the TCR2 Board were regarded as less attractive at this time or impractical. The TCR2 Board also directed TCR2 senior management to take additional actions to reduce costs and preserve available cash in order to extend TCR2’s cash runway through key clinical milestones.
During August 2022, TCR2 and Party A continued intermittent discussions regarding a potential business combination transaction. In early September 2022, Party A terminated discussions with TCR2 to
 
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focus on discussions that were underway with a global biopharmaceutical company much larger than TCR2 that would ultimately acquire Party A. No further discussions between TCR2 and Party A occurred after this time.
From September 21 through 24, 2022, in order to gauge investor interest in a potential investment in TCR2’s securities, either in a public or private offering, TCR2 wall-crossed approximately a dozen institutional investors and had discussions regarding TCR2’s gavo-cel clinical data prior to its public announcement. These discussions did not ultimately result in an offering that was regarded as sufficiently attractive by the Finance & Strategy Committee of the TCR2 Board (the “F&S Committee”). The TCR2 Board had established the F&S Committee in 2016 to, among other matters, consider and make recommendations to the TCR2 Board regarding matters impacting TCR2’s financial structure and strategic direction, including, but not limited to, TCR2’s capital structure, business development activities, and financing strategy, as well as the overall scope and focus of TCR2’s business and operations.
On September 28, 2022, TCR2 announced positive topline results from the Phase 1 portion of the gavo-cel Phase 1/2 clinical trial for mesothelin-expressing solid tumors with an overall response rate for ovarian cancer patients infused with gavo-cel following lymphodepletion of approximately 29%, and an overall response rate for mesothelioma patients infused with gavo-cel following lymphodepletion of approximately 21%.
On October 6, 2022, the TCR2 Board held a regularly scheduled meeting at which members of TCR2 senior management and representatives of Goodwin were present. At this meeting, TCR2 senior management provided a business update to the TCR2 Board. The TCR2 Board discussed the risks, challenges, and strategic opportunities facing TCR2, taking into consideration the recent clinical data released on gavo-cel that indicated an overall response rate that was higher for ovarian cancer than mesothelioma. The TCR2 Board considered that ovarian cancer is a much larger indication than mesothelioma, and TCR2 senior management reported that potential biopharmaceutical partners and investors were more interested in outcomes from that cohort of the clinical trial. The TCR2 Board also considered the risks and challenges facing TCR2 as a result of then-current macro-economic, industry and market conditions, its then-current cash position, the need for meaningful capital investment to advance TCR2’s product candidates, and the lack of attractive financing alternatives at that time. The TCR2 Board and TCR2 senior management discussed that given the risks and challenges facing TCR2 discussed at this meeting, a low likelihood existed that third parties would be interested in providing equity financing to TCR2 until the next potential clinical data catalysts that might positively influence TCR2’s stock price in the second half of 2023. Following discussion, the TCR2 Board directed TCR2 senior management to prepare a proposal for a potential reprioritization of TCR2 resources to focus on completing the ovarian cancer cohort in the Phase 2 clinical trial of gavo-cel and to deprioritize the mesothelioma studies.
Also at this meeting, TCR2 senior management reported on its continued evaluation of a range of potential strategic alternatives covering business development opportunities and mergers and acquisition strategies in which the scope had been broadened following the termination of discussions with Party A to include T-cell therapy companies that were of equivalent or greater size than TCR2. The TCR2 Board also was updated on the periodic discussions held by TCR2 senior management with other parties in the cell therapy field. As part of this presentation, Adaptimmune was identified and discussed as the most compelling and practical counterparty for a potential business combination through an all-stock merger with TCR2, based on criteria including market capitalization, clinical validation of the underlying technology, therapeutic indications of lead clinical assets, potential catalysts, complementary underlying technologies, synergistic capabilities, including proven ability to execute clinical trials and complex manufacturing processes, physical location in the U.S., cash positions, and cash runway. The meeting participants also discussed another publicly traded cell therapy company (“Party B”) as a potential counterparty for such a transaction but concluded that Party B’s then-much larger market capitalization would prevent TCR2 stockholders from owning a meaningful portion of the post-closing combined company. An overview of Adaptimmune’s and Party B’s respective businesses, the strategic rationale and other considerations for Adaptimmune’s and Party B’s potential combination with TCR2, and high-level financial information (based on publicly available information) were presented and discussed. Following discussion, and in connection with TCR2’s continued exploration of potential strategic alternatives, the TCR2 Board determined to approach Adaptimmune to ascertain its interest in a potential business combination transaction with TCR2 in light of Adaptimmune’s
 
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complementary platform and singular focus on solid tumors. Given that Dr. Garry Menzel, President and Chief Executive Officer of TCR2, had a longstanding relationship with Adrian Rawcliffe, Chief Executive Officer of Adaptimmune, the TCR2 Board authorized Dr. Menzel to conduct the initial outreach to Adaptimmune.
On the evening of October 25, 2022, Dr. Menzel and Mr. Rawcliffe met for dinner in Philadelphia, Pennsylvania, at the invitation of Dr. Menzel. During this dinner, the executives discussed the state of the biotechnology industry generally, shared their common belief that consolidation was expected in the cell therapy sector, and discussed the strategic rationale that could support being a first mover in such consolidation through a potential business combination of Adaptimmune and TCR2. Following this meeting, Adaptimmune reviewed publicly available information on TCR2 to further assess TCR2’s technology and whether a combination between Adaptimmune and TCR2 could potentially be beneficial to Adaptimmune.
On the evening of November 2, 2022, Dr. Menzel and Mr. Rawcliffe met again for dinner in Philadelphia, Pennsylvania to further discuss cell therapy consolidation and the strategic rationale and other considerations that would be critical for a successful combination of Adaptimmune and TCR2, including the timing of executing such a transaction. During this dinner, Dr. Menzel informed Mr. Rawcliffe of TCR2’s interest in exploring a potential business combination transaction with Adaptimmune. Mr. Rawcliffe agreed that a compelling strategic rationale for a business combination existed. During these discussions, no economic terms were proposed by either Dr. Menzel or Mr. Rawcliffe with respect to a strategic transaction. Following the meeting, the parties agreed to discuss further such potential business combination with a broader group of individuals from each company at a meeting planned in Boston, Massachusetts for December 6, 2022.
On November 8, 2022, Adaptimmune announced data from its phase 1 SURPASS trial with an overall response rate of 52% across ovarian, urothelial and head and neck cancers. Also, on November 8, 2022, in its third-quarter financial results and business update, Adaptimmune announced it would focus its programs in MAGE-A4 and PRAME T-cell targets, would initiate a rolling BLA submission for afami-cel for the treatment of synovial sarcoma in the fourth-quarter of 2022 and that, to extend its cash runway into early 2025, it would de-prioritize non-core programs and undertake a significant restructuring with a reduction in headcount of approximately 25% to 30%.
On November 21, 2022, the TCR2 Board held an update call regarding TCR2 clinical operations matters at which members of TCR2 senior management provided an update on initiatives to increase patient enrollment. Also, during the call, Dr. Menzel reported on his recent discussions with Adaptimmune and its perceived level of interest in a potential business combination transaction with TCR2. After discussion, the TCR2 Board authorized TCR2 senior management to continue discussions with Adaptimmune. The TCR2 Board also discussed the recent decline of the market capitalization of Party B and, given the prior discussion regarding Party B at the October 6, 2022 TCR2 Board meeting, the TCR2 Board authorized a non-management, independent director who had a business relationship with a representative of Party B to inquire whether there was any interest on the part of Party B in a business combination transaction with another cell therapy company.
On December 1, 2022, Dr. Menzel and Mr. Rawcliffe had a discussion to identify the key principles underlying the strategic rationale for a potential business combination of TCR2 and Adaptimmune, which would be discussed at the planned meeting on December 6, 2022.
On December 2, 2022, Dr. Menzel sent a draft mutual confidentiality agreement to Mr. Rawcliffe. Between December 2, 2022 and December 6, 2022, Mr. Rawcliffe and Dr. Menzel communicated to discuss the proposed agenda and attendees for the potential meeting on December 6, 2022.
On December 6, 2022, members of TCR2 senior management met with members of Adaptimmune management in Boston, Massachusetts and engaged in preliminary discussions regarding their respective capabilities and the operational implications of a potential business combination transaction involving TCR2 and Adaptimmune. Adaptimmune and TCR2 entered into a mutual confidentiality agreement, effective as of December 6, 2022 (the “December 6 NDA”), to enable the parties to engage in confidential discussions in respect of a potential negotiated business arrangement between the parties. The December 6 NDA did not contain standstill obligations.
 
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On December 14, 2022, members of TCR2 senior management had discussions with members of Adaptimmune management to follow up on the discussions of December 6, 2022. The discussions focused on understanding potential research and development catalysts, overlapping capabilities, cash position, and cash runway of a potential combined company.
On December 15, 2022, the TCR2 Board held a regularly scheduled meeting at which members of TCR2 senior management and representatives of Goodwin were present. At this meeting, TCR2 senior management provided a business update to the TCR2 Board. This meeting was held to, among other things, consider senior management’s proposed plan to reprioritize aspects of TCR2’s business and programs that was requested by the TCR2 Board at the October 6, 2022 TCR2 Board meeting. TCR2 senior management provided an update on the progress with key clinical and preclinical programs as well as a financial budget for 2023 that took into account the continued negative financing environment for biopharmaceutical companies. Following discussion, the TCR2 Board determined that it would be in the best interests of TCR2 and TCR2 stockholders for TCR2 to narrow its pipeline priorities for 2023 to concentrate resources on completing the ovarian cancer cohort in the Phase 2 clinical trial of gavo-cel and accelerate development of its second-generation enhanced TRuC T-cell therapy programs, TC-510 and TC-520. The TCR2 Board authorized TCR2 senior management to proceed with implementing various actions to refocus TCR2 business on these pipeline priorities, including preserving cash available by adjusting its manufacturing network and seeking to exit the lease related to its Rockville, Maryland manufacturing facility, with a reduction in force aligned with such changes, on such timeline as TCR2 senior management deemed to be in TCR2’s best interest.
Also at the meeting, TCR2 senior management reported on the recent discussions with Adaptimmune and its perceived level of interest in a potential business combination transaction with TCR2. The TCR2 Board also discussed that Party B had declined any interest in a business combination with another cell therapy company. The TCR2 Board also determined that no other cell therapy company had as compelling a strategic logic as Adaptimmune and that no changes had occurred in the companies previously identified as potential strategic transaction partners that warranted further analysis. After discussion, the TCR2 Board authorized TCR2 senior management to continue discussions with Adaptimmune.
On January 3, 2023, Dr. Menzel and Mr. Rawcliffe shared perspectives from their respective discussions with certain members of their respective boards of directors and discussed operational considerations for the potential business combination of Adaptimmune and TCR2.
On January 5, 2023, TCR2 publicly announced its pipeline priorities for 2023 to concentrate its resources on completing the ovarian cancer cohort in the Phase 2 clinical trial of gavo-cel and accelerating the development of its second-generation enhanced TRuC T-cell therapy programs, TC-510 and TC-520. As part of the prioritization, TCR2 publicly announced a plan for TCR2 to reduce its workforce by approximately 40% and also adjust its manufacturing network.
Also, on January 5, 2023, TCR2 senior management received an unsolicited inbound inquiry from a financial advisor for a privately-held T-cell therapy company (“Party C”) indicating that TCR2’s January 5, 2023 announcement prompted Party C to inquire whether TCR2 would be interested in discussing a potential strategic transaction with Party C. In response, TCR2 senior management indicated that they would be amenable to having a discussion. Party C, however, was known to TCR2, and TCR2 senior management did not view Party C as a potential candidate for a strategic transaction with TCR2 because Party C lacked clinical validation of its underlying technology, among other factors, which failed to satisfy the criteria discussed at the October 6, 2022 TCR2 Board meeting.
On January 6, 2023, the Adaptimmune Board convened by videoconference with members of Adaptimmune management attending. Among other matters that were discussed, Mr. Rawcliffe provided the Adaptimmune Board with an overview of the potential opportunity for a business combination of Adaptimmune and TCR2. Following discussion, the Adaptimmune Board authorized Mr. Rawcliffe and Adaptimmune management to further explore the potential opportunity with TCR2.
Also, on January 6, 2023, TCR2 senior management discussed a potential strategic transaction with Party C’s financial advisor.
 
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Between January 11, 2023 and January 12, 2023, representatives of Adaptimmune and TCR2 met at the J.P. Morgan Healthcare Conference in San Francisco and at the offices of Goodwin, to discuss a potential business combination transaction. Also during this conference, representatives of Adaptimmune met with representatives of TD Cowen to discuss TD Cowen’s possible engagement as a financial advisor to Adaptimmune. Adaptimmune subsequently engaged TD Cowen to act as its financial advisor in connection with the potential business combination. Among the factors considered in engaging TD Cowen were TD Cowen’s reputation as a nationally recognized investment banking firm, its experience with similar transactions, TD Cowen’s familiarity with Adaptimmune and its business and industry, and the disclosure TD Cowen provided to the Adaptimmune Board indicating that TD Cowen did not have any material relationships with TCR2 during the two-year period prior to such disclosure.
Also, on January 12, 2023, the Adaptimmune and TCR2 teams engaged in preliminary reciprocal due diligence discussions.
Also, during the J.P. Morgan Healthcare Conference, members of TCR2 senior management had business development discussions with other parties (including Party C) that might have potential interest in a strategic transaction with TCR2; however, none of these other parties (other than Party C) expressed interest in a strategic transaction with TCR2.
On January 18, 2023, Dr. Menzel and Mr. Rawcliffe had a discussion to review initial reactions to the preliminary reciprocal due diligence process.
On January 19, 2023, members of TCR2 senior management and Adaptimmune management engaged in discussions regarding the two parties’ respective clinical development and research programs and clinical data. Additionally, TCR2 granted Adaptimmune access to a virtual data room to enable Adaptimmune to perform its due diligence review of TCR2.
On January 21, 2023, members of TCR2 senior management preliminarily discussed with representatives of Piper Sandler TCR2’s business and prospects and the possibility of acting as its financial advisor in evaluating any proposals that might be received from Adaptimmune or any other parties. TCR2 considered Piper Sandler as a potential financial advisor to assist and advise TCR2 given, among other things, Piper Sandler’s qualifications, experience, and reputation; its knowledge of and involvement in recent transactions in the biopharmaceutical industry; and its familiarity with clinical-stage cell therapy companies such as TCR2, including through its prior involvement in assisting TCR2 in connection with prior TCR2 equity offerings.
On January 23, 2023, the Adaptimmune Board convened by videoconference with members of Adaptimmune management and Ropes & Gray LLP (“Ropes & Gray”), legal advisor to Adaptimmune, attending to discuss the potential opportunity with TCR2, including TCR2’s strategic profile and possible financial and strategic rationale, and considerations in evaluating a potential business combination transaction. Mr. Rawcliffe updated the Adaptimmune Board on the discussions with TCR2, including providing the Adaptimmune Board with initial feedback following the January 19 meeting with TCR2. The Adaptimmune Board and Adaptimmune management also discussed potential terms for a non-binding proposal, a draft of which was provided to the Adaptimmune Board prior to the meeting. A representative of Ropes & Gray provided the Adaptimmune Board with an overview of the fiduciary duties of directors, including the obligation to act in good faith to promote the success of Adaptimmune for the benefit of its shareholders as a whole. Following discussion, the Adaptimmune Board authorized Adaptimmune management to submit the non-binding proposal to TCR2 on the terms previously reviewed by and discussed with the Adaptimmune Board at the meeting.
Later that day, Mr. Rawcliffe called Dr. Menzel to inform him that Mr. Rawcliffe would be sending a non-binding proposal (the “January 23 Proposal”), which Mr. Rawcliffe subsequently sent to Dr. Menzel. The January 23 Proposal proposed to combine TCR2 and Adaptimmune in an all-stock transaction. Among other terms, the January 23 Proposal offered consideration of Adaptimmune ADSs for each outstanding share of TCR2 Common Stock such that TCR2 stockholders immediately prior to consummation of the proposed transaction would own approximately 20% of the combined company immediately following closing of the proposed transaction. The January 23 Proposal also proposed a 30-day exclusivity period, that TCR2 would receive board representation on the combined company’s board of directors equal to the equity split in the combined company, and that directors, officers, and certain key stockholders of TCR2 would enter into voting agreements and lock-up agreements in connection with the proposed transaction.
 
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On January 24, 2023, the F&S Committee held a meeting at which members of TCR2 senior management and representatives of Goodwin were present. At this meeting, Dr. Menzel reported on recent discussions with Adaptimmune and receipt of the January 23 Proposal. Following discussion, the F&S Committee instructed Dr. Menzel to pause discussions with Adaptimmune and determined to further discuss the January 23 Proposal with the TCR2 Board at an upcoming meeting. Also at this meeting, the F&S Committee discussed the advisability of engaging a financial advisor to assist TCR2 in its evaluation and negotiation of the January 23 Proposal and any other proposals for strategic transactions that might be received. Following this discussion, the F&S Committee authorized TCR2 senior management to continue discussions with potential financial advisor candidates. Following this meeting, members of TCR2 senior management further discussed with representatives of Piper Sandler and representatives of another investment bank the possibility of acting as TCR2 financial advisor in evaluating Adaptimmune’s January 23 Proposal and any other proposals for strategic transactions that might be received. Representatives of Goodwin also requested that Piper Sandler provide customary disclosure regarding their relationships with Adaptimmune for review with the TCR2 Board.
Also, on January 24, 2023, representatives of TCR2 senior management had a preliminary discussion with the financial advisor of Party C regarding TCR2’s potential interest in a transaction with Party C, which was indicated to be a so-called “reverse merger” transaction in which Party C would take control of TCR2 to access TCR2’s cash balance and public listing status. TCR2 senior management indicated that, if there was definitive interest from Party C in such a potential transaction, then Party C should follow up with TCR2. Party C did not follow up, and no further discussion between TCR2 and Party C occurred after this time.
On January 26, 2023, the TCR2 Board held a meeting at which members of TCR2 senior management and representatives of Piper Sandler and Goodwin were present. At the meeting, Dr. Menzel reported to the TCR2 Board regarding his recent conversations with Mr. Rawcliffe and receipt of the January 23 Proposal. Representatives of Goodwin reviewed with the members of the TCR2 Board their fiduciary duties. Representatives of Piper Sandler then discussed certain publicly available market data regarding TCR2 and Adaptimmune. The TCR2 Board directed TCR2 senior management to develop a long-term plan and projections for consideration by the TCR2 Board. Following discussion, the TCR2 Board determined that the January 23 Proposal did not adequately reflect TCR2’s value and i