Marketable Securities - Graphite Bio, Inc. (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Schedule of Marketable Securities

The Company did not hold any marketable securities as of December 31, 2023. The amortized cost, gross unrealized holding gains or losses, and fair value of the Company’s marketable securities by major security type as of December 31, 2022 are summarized in the table below (in thousands):

	December 31, 2022
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses		Fair Value
Available-for-sale securities
U.S. treasuries	$	65,807	$	—	$	(416)	$	65,391
Commercial paper	115,381		13		(333)		115,061
U.S. agency securities	53,767		15		(327)		53,455
Asset-backed securities	1,914		—		—		1,914
Total available-for-sale securities	$	236,869	$	28	$	(1,076)	$	235,821

Marketable securities consisted of the following (in thousands):

	December 31, 2023
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Commercial paper	$	18,742	$	9	$	—	$	18,751
US government agencies	9,927		1		(3)		9,925
US treasury securities	1,977		1		—		1,978
Totals	$	30,646	$	11	$	(3)	$	30,654