Short-Term Investments

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

Note 7. Short-Term Investments

Marketable Securities

The following table provides amortized costs, gross unrealized gains and losses, and fair values for the Company’s investments in available-for-sale U.S. treasury securities as of September 30, 2025 and December 31, 2024, which have maturity dates that range from 2 months to 11 months and 0 month to 10 months, respectively. Fair value was determined using market prices obtained from third-party sources. Realized gains or losses were insignificant for the three and nine months ended September 30, 2025 and 2024.


September 30, 2025			Gross		Gross
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. treasury securities	$	177,388	$	171	$	—	$	177,559
Total short-term marketable securities	$	177,388	$	171	$	—	$	177,559

December 31, 2024			Gross		Gross
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. treasury securities	$	132,615	$	167	$	—	$	132,782
Total short-term marketable securities	$	132,615	$	167	$	—	$	132,782

The Company has $1.2 million and $1.0 million marketable equity securities as of September 30, 2025 and December 31, 2024, respectively, with an initial cost of $0.5 million. Total unrealized gain of $0.7 million and $0.5 million is recorded under miscellaneous (expense) income, net in the condensed consolidated statements of operations and comprehensive loss for the periods ended September 30, 2025 and December 31, 2024, respectively.

SES AI Corp 10-Q