Share-based compensation (Tables)
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12 Months Ended |
Dec. 31, 2017 |
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| Summary of vesting information |
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Options granted in 2009:
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100% on the third anniversary of the grant date
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Options granted in 2011, 2012, 2013 and April 2014:
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25% on the first anniversary of the grant date and 75% in annual installments over the following three years
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Options granted in December 2014:
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25% on the first anniversary of the grant date and 75% in monthly installments over the following three years
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| Summary of share-based compensation expense included in the consolidated statement of operations |
The following table shows the total share-based compensation expense included in the consolidated statement of operations (thousands):
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Year ended
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Year ended
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Six months ended
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Year ended
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December 31,
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December 31,
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December 31,
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June 30,
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2017
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2016
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2015
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2015
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Research and development
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$
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5,268
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$
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4,185
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$
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1,587
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$
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5,426
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General and administrative
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5,536
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4,636
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1,981
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1,652
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$
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10,804
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$
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8,821
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$
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3,568
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$
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7,078
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| Summary of all stock option activity |
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Weighted
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Average
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average
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remaining
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Aggregate
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exercise price
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contractual
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intrinsic value
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Options
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per option
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term (years)
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(thousands)
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Outstanding at January 1, 2017
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49,237,290
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£
|
0.58
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Changes during the period:
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Granted
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29,924,787
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£
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0.62
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Exercised
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(1,142,904
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)
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£
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0.19
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Forfeited
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(3,075,506
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)
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£
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1.04
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Outstanding at December 31, 2017
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74,943,667
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£
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0.58
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7.9
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$
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84,989
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Exercisable at December 31, 2017
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31,449,602
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£
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0.51
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6.8
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$
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35,665
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| Summary of information about stock options outstanding |
The following table summarizes information about stock options outstanding as of December 31, 2017:
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Outstanding
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Exercisable
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Weighted-
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average
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Weighted-
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Weighted-
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Total share
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remaining
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average
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Total share
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average exercise
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Exercise price
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options
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contractual life
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exercise price
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options
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price
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£
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0 – 0.25
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9,224,274
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5.6
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£
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0.12
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8,508,100
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£
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0.12
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0.26 – 0.50
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9,694,008
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7.0
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0.36
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7,477,900
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0.36
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0.51 – 0.75
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38,859,727
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8.7
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0.58
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6,615,358
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0.51
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0.76 – 1.00
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13,986,392
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7.9
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0.90
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7,405,720
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0.91
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1.01 – 1.50
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2,313,651
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8.9
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1.05
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576,909
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1.06
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1.51 – 2.00
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865,615
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4.9
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1.82
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865,615
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1.82
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Total
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74,943,667
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|
7.9
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£
|
0.58
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|
31,449,602
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£
|
0.51
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| Summary of the assumptions used to estimate the fair values of the share options granted using the Black-Scholes option-pricing model |
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Year ended
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Year ended
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Year ended
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December 31,
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December 31,
|
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June 30,
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2017
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2016
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2015
|
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Expected term (years)
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5 years
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5 years
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5 years
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Expected volatility
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66-71%
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68-73%
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60%
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Risk free rate
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0.40-0.76%
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0.17-1.07%
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1.04-1.54%
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Expected dividend yield
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0%
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0%
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0%
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| Non-executive director |
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| Summary of vesting information |
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Options granted to non-executive directors on May 11, 2015:
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Immediately on grant date
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Options granted to a non-executive director on June 23, 2016:
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25% on the first anniversary of the grant date and 75% in monthly installments over the following two years
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|
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Options granted to non-executive directors on August 11, 2016:
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100% on the first anniversary of the grant date
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Options granted to non-executive directors on November 28, 2016:
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25% on the first anniversary of the grant date and 75% in monthly installments over the following two years
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Options granted to non-executive directors on July 3, 2017
|
|
100% on the first anniversary of the grant date
|
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