Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Common Stock in Treasury	Non- controlling Interest
Common stock, beginning balance (in shares) at Sep. 30, 2024		124,376,000
Beginning balance at Sep. 30, 2024	$ 191,063	$ 217	$ 1,806,000	$ 4,750	$ (1,625,523)		$ 5,619
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	15,209		15,209
Exercise of stock options (in shares)		70,000
Exercise of stock options	634		634
Common stock - restricted stock units vesting (in shares)		209,000
Issuance of pre-funded warrants (in shares)		917,000
Issuance of pre-funded warrants	25,000	$ 1	24,999
Foreign currency translation adjustments	(106)			(106)
Unrealized gains (losses) on available-for-sale securities	(507)			(507)
Net income (loss)	(175,218)				(173,085)		(2,133)
Common stock, ending balance (in shares) at Dec. 31, 2024		125,572,000
Ending balance at Dec. 31, 2024	$ 56,075	$ 218	1,846,842	4,137	(1,798,608)		3,486
Common stock, beginning balance (in shares) at Sep. 30, 2025	135,702,000	138,363,000
Beginning balance at Sep. 30, 2025	$ 503,416	$ 231	2,139,725	6,443	(1,627,154)	$ (53,193)	37,364
Treasury stock, beginning balance (in shares) at Sep. 30, 2025	(2,661,000)					(2,661,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	$ 19,371		19,371
Exercise of stock options (in shares)	296,682	296,000
Exercise of stock options	$ 5,098		5,098
Common stock - restricted stock units vesting (in shares)		704,000
Common stock - restricted stock units vesting	2	$ 1	1
Issuance of common stock under at-the-market offering, net of issuance costs (in shares)		689,000
Issuance of common stock under at-the-market offering, net of issuance costs	46,832	$ 1	46,831
Foreign currency translation adjustments	110			110
Unrealized gains (losses) on available-for-sale securities	146			146
Dividends declared by variable interest entity to noncontrolling shareholders	(40,520)						(40,520)
Net income (loss)	$ 28,242				30,811		(2,569)
Common stock, ending balance (in shares) at Dec. 31, 2025	137,391,000	140,052,000
Ending balance at Dec. 31, 2025	$ 562,697	$ 233	$ 2,211,026	$ 6,699	$ (1,596,343)	$ (53,193)	$ (5,725)
Treasury stock, ending balance (in shares) at Dec. 31, 2025	(2,661,000)					(2,661,000)

ARROWHEAD PHARMACEUTICALS, INC. 10-Q