
September 30, 2024	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
(in thousands)
Money Market Funds	$	21,028	$	—	$	—	$	21,028
Corporate Securities	161,118		525		—		161,643
Government Securities	562,387		1,419		(132)		563,674
	$	744,533	$	1,944	$	(132)	$	746,345

Reported as
Cash and cash equivalents							$	21,028
Marketable securities							725,317
Total investments							$	746,345


December 31, 2023	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
(in thousands)
Money Market Funds	$	25,520	$	—	$	—	$	25,520
Corporate Securities	228,382		342		(1)		228,723
Government Securities	413,553		1,037		(76)		414,514
	$	667,455	$	1,379	$	(77)	$	668,757

Reported as
Cash and cash equivalents							$	25,520
Marketable securities							643,237
Total investments							$	668,757


September 30, 2024	Amortized Cost		Estimated Fair Value
(in thousands)
Mature in one year or less	$	433,602	$	435,043
Mature within two years	289,903		290,274
	$	723,505	$	725,317


	Less than 12 months				12 months or greater
September 30, 2024	Fair value		Unrealized losses		Fair value		Unrealized losses
(in thousands)

Government Securities	$	—	$	—	$	198,710	$	(132)


	Less than 12 months				12 months or greater
December 31, 2023	Fair value		Unrealized losses		Fair value		Unrealized losses
(in thousands)
Corporate Securities	$	8,073	$	(1)	$	—	$	—
Government Securities	66,546		(76)		—		—
	$	74,619	$	(77)	$	—	$	—

The unrealized losses from the available-for-sale securities are due to changes in the interest rate environment and not changes in the credit quality of the underlying securities in the portfolio.

The Company’s equity securities include securities with a readily determinable fair value and securities without a readily determinable fair value. Equity securities with a readily determinable fair value are carried at fair value with changes in fair value recognized each period and reported within other income (expense), net. For equity securities without a readily determinable fair value, the Company elects the measurement alternative to record these investments at their initial cost and evaluates such investments at each reporting period for evidence of impairment, or observable price changes in orderly transactions for the identical or a similar investment of the same issuer.

The Company sold 443,909 shares of common stock of Astria Therapeutics, Inc. (Astria) in the second quarter of 2024, and sold the remaining 253,958 shares of common stock of Astria in July 2024. The Company does not hold any shares of common stock of Astria as of September 30, 2024. The Company recorded realized gains of $0.1 million and $1.3 million for the three and nine months ended September 30, 2024, respectively. The Company held 697,867 shares of common stock as of September 30, 2023, which were classified as equity securities with a readily determinable fair value. The Company recorded unrealized losses of $0.6 million and $4.5 million for the three and nine months ended September 30, 2023, respectively.

The Company currently holds 1,885,533 shares of common stock of INmune Bio, Inc. (INmune). The 1,885,533 shares of INmune common stock are classified as equity securities with a readily determinable fair value. For the three and nine months ended September 30, 2024, the Company recorded unrealized losses of $6.5 million and $11.1 million, respectively. For the three and nine months ended September 30, 2023, the Company recorded an unrealized loss of $4.4 million and an unrealized gain of $0.8 million, respectively.

The Company currently holds 717,144 shares of common stock of Viridian Therapeutics, Inc. (Viridian). The shares of Viridian common stock are classified as equity securities with a readily determinable fair value. The Company recorded unrealized gains of $7.0 million and $0.7 million for the three and nine months ended September 30, 2024, respectively. The Company recorded unrealized losses of $6.1 million and $9.9 million for the three and nine months ended September 30, 2023, respectively.

The Company holds an equity interest in Zenas BioPharma, Inc. (Zenas). The Company’s equity interests previously included preferred stock in Zenas when Zenas was a privately-held company. The preferred shares were received as an upfront payment and a milestone payment for licensing certain clinical and preclinical assets from the Company and did not have a readily determinable fair value. The Company elected the measurement alternative to carry the Zenas equity at cost minus impairment, plus or minus changes resulting from observable price changes in an orderly transaction for the identical or a similar investment of the same issuer. During the six months ended June 30, 2024, the Company recorded $20.4 million of impairment charge due to an impairment analysis using the measurement alternative for the valuation of a security without a readily determinable fair value.

On September 16, 2024, following the closing of Zenas' initial public offering, the Company's preferred stock in Zenas was automatically converted to 3,098,380 shares of common stock which were then classified as equity securities with a readily determinable fair value. The Company subsequently discontinued the use of the measurement alternative in valuing its equity interest in Zenas. As a result, the Company recorded an unrealized gain of $8.6 million for each of the three and nine months ended September 30, 2024.

Equity securities with a readily determinable fair value, which are categorized as Level 1 in the fair value hierarchy under ASC 820, and their fair values (in thousands) as of September 30, 2024 and December 31, 2023 are as follows:


	Fair Value		Fair Value
	September 30, 2024		December 31, 2023
Astria Common Stock	$	—	$	5,360
INmune Common Stock	10,163		21,231
Viridian Common Stock	16,315		15,619
Zenas Common Stock	52,425		—
	$	78,903	$	42,210

Net gain (loss) recorded related to these equity securities are recorded under other income (expense). Below is a reconciliation of net gain (loss) recorded on equity securities during the three and nine months ended September 30, 2024 and 2023:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Net gain (loss) recorded on equity securities	$	9,254	$	(11,023)	$	(448)	$	(13,633)
Less: Net gain recorded on sale of equity securities	92		—		1,280		—
Unrealized gain (loss) recorded on equity securities held at the reporting date	$	9,162	$	(11,023)	$	(1,728)	$	(13,633)