Fair Value Measurements

9 Months Ended

Sep. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

The following tables present the financial instruments carried at fair value on a recurring basis as of September 30, 2024 and December 31, 2023, respectively, in accordance with the ASC 820, Fair Value Measurement (ASC 820) hierarchy (in thousands):

	Fair Value Measurements at September 30, 2024
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	17,861	$	—	$	—	$	17,861
Marketable securities	$	—	$	497,299	$	—	$	497,299
	Fair Value Measurements at December 31, 2023
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	8,240	$	—	$	—	$	8,240
Marketable securities	$	—	$	179,408	$	—	$	179,408
Liabilities
Success fee liability	$	—	$	—	$	365	$	365

The Company’s cash equivalents represent deposits in a short-term U.S. Treasury money market fund quoted in an active market and were classified as a Level 1 fair value measurement. Marketable securities represent fixed income securities (U.S. treasury bills) with original maturities greater than 90 days and were classified as a Level 2 fair value measurement. As of September 30, 2024 and December 31, 2023, the amortized cost of the Company's available for sale marketable securities approximated their fair value. There was no material realized or unrealized gains or losses, either individually or in the aggregate.

The success fee liability associated with the Loan and Security Agreement (the Loan Agreement) the Company entered into in January 2021 was classified as a Level 3 fair value measurement, due to the use of unobservable inputs. On March 5, 2024, the Company paid $0.4 million for the success fee. See Note 10 for additional information on the success fee.

There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the three and nine months ended September 30, 2024 and the year ended December 31, 2023.