Note 6 — Marketable securities – available-for-sale debt securities

As of September 30, 2020, the Company has the following investments in marketable securities (in thousands):

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As of September 30, 2020 and December 31, 2019, the aggregate fair value of securities held by the Company in an unrealized loss position was $135.0 million and $2.0 million respectively, which consisted of 23 and 1 separate securities, respectively. No securities have been in an unrealized loss position for more than one year.

As of September 30, 2020, the securities in an unrealized loss position are not considered to be other than temporarily impaired because the impairments are not severe and have been for a short duration. The Company does not intend to sell the debt securities in an unrealized loss position and believes that it has the ability to hold the debt securities to maturity.