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
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Uncategorized
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- Insider Trading Arrangements

Marketable securities - Available-for-sale debt securities - Unrealized loss position (Details)

v3.23.3

Marketable securities - Available-for-sale debt securities - Unrealized loss position (Details) $ in Thousands	Sep. 30, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Marketable securities
Fair market value of investments in an unrealized loss position	$ 26,692	$ 90,618
Number of investments in an unrealized loss position \| security	9	19
Unrealized losses	$ (13)	$ (930)
Corporate debt securities
Marketable securities
Fair market value of investments in an unrealized loss position, 12 months or longer	2,377	74,481
Fair market value of investments in an unrealized loss position, less than 12 months	$ 6,440	$ 11,283
Number of available-for-sale securities in an unrealized loss position, 12 months or longer \| security	1	16
Number of available-for-sale securities in an unrealized loss position, less than 12 months \| security	2	2
Unrealized losses, 12 months or longer	$ (6)	$ (679)
Unrealized losses, less than 12 months	(1)	(97)
U.S. Treasury securities
Marketable securities
Fair market value of investments in an unrealized loss position, less than 12 months	$ 14,894
Number of available-for-sale securities in an unrealized loss position, less than 12 months \| security	5
Unrealized losses, less than 12 months	$ (3)
Agency bonds
Marketable securities
Fair market value of investments in an unrealized loss position, 12 months or longer		$ 4,854
Fair market value of investments in an unrealized loss position, less than 12 months	$ 2,981
Number of available-for-sale securities in an unrealized loss position, 12 months or longer \| security		1
Number of available-for-sale securities in an unrealized loss position, less than 12 months \| security	1
Unrealized losses, 12 months or longer		$ (154)
Unrealized losses, less than 12 months	$ (3)

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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