Adaptimmune Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Marketable securities - available-for-sale debt securities (Details)

v3.20.2

Marketable securities - available-for-sale debt securities (Details) $ in Thousands	Sep. 30, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Marketable securities
Fair market value of investments in an unrealized loss position	$ 135,000	$ 2,000
Number of debt securities \| security	23	1
Number of available-for-sale securities in an unrealized loss position for more than one year \| security	0
Debt Securities
Marketable securities
Amortized cost	$ 321,156
Gross unrealized gains	468
Gross unrealized losses	(182)
Aggregate estimated fair value	321,442
Corporate Debt Securities Maturity Period Less Than Three Months \| Debt Securities
Marketable securities
Amortized cost	14,272
Gross unrealized gains	16
Gross unrealized losses	(4)
Aggregate estimated fair value	14,284
Corporate Debt Securities Maturity Period Three Months To One Year
Marketable securities
Amortized cost	164,830
Gross unrealized gains	336
Gross unrealized losses	(40)
Aggregate estimated fair value	165,126
Corporate Debt Securities Maturity Period One Year To Two Years \| Debt Securities
Marketable securities
Amortized cost	136,058
Gross unrealized gains	107
Gross unrealized losses	(138)
Aggregate estimated fair value	136,027
Agency Bond Maturity Period One Year To Two Years \| Debt Securities
Marketable securities
Amortized cost	5,996
Gross unrealized gains	9
Aggregate estimated fair value	$ 6,005

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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