Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Beginning Balance at Dec. 31, 2024	$ 420,047	$ 44	$ 538,321	$ 56	$ (118,374)
Beginning Balance (in shares) at Dec. 31, 2024		44,422,505
Issuance of common stock upon exercise of stock options	66		66
Issuance of common stock upon exercise of stock options (in shares)		25,930
Vesting of restricted common stock	5		5
Stock-based compensation expense	1,482		1,482
Net unrealized gain (loss) on marketable securities	142			142
Net loss	(21,476)				(21,476)
Ending Balance at Mar. 31, 2025	(400,266)	$ 44	539,874	198	(139,850)
Ending Balance (in shares) at Mar. 31, 2025		44,448,435
Beginning Balance at Dec. 31, 2025	381,926	$ 45	548,517	617	(167,253)
Beginning Balance (in shares) at Dec. 31, 2025		44,806,272
Issuance of common stock upon exercise of stock options	335		335
Issuance of common stock upon exercise of stock options (in shares)		110,300
Vesting of restricted common stock	5		5
Stock-based compensation expense	6,015		6,015
Net unrealized gain (loss) on marketable securities	(1,186)			(1,186)
Net loss	(8,637)				(8,637)
Ending Balance at Mar. 31, 2026	$ 378,458	$ 45	$ 554,872	$ (569)	$ (175,890)
Ending Balance (in shares) at Mar. 31, 2026		44,916,572

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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+ Details

Septerna, Inc. 10-Q