Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2023		60,998
Beginning balance at Dec. 31, 2023	$ 662,087	$ 611	$ 1,131,266	$ 1,291	$ (471,418)	$ 337
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	11,421		11,421
Exercise of stock options (in shares)		153
Exercise of stock options	1,787	$ 1	1,786
Issuance of restricted stock units (in shares)		484
Issuance of restricted stock units	0	$ 5	(5)
Net unrealized gain (loss) on marketable debt securities	(1,445)			(1,445)
Net loss	(74,116)				(73,440)	(676)
Ending balance (in shares) at Mar. 31, 2024		61,635
Ending balance at Mar. 31, 2024	599,734	$ 617	1,144,468	(154)	(544,858)	(339)
Beginning balance (in shares) at Dec. 31, 2023		60,998
Beginning balance at Dec. 31, 2023	662,087	$ 611	1,131,266	1,291	(471,418)	337
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net unrealized gain (loss) on marketable debt securities	510
Net loss	(190,340)
Ending balance (in shares) at Sep. 30, 2024		69,963
Ending balance at Sep. 30, 2024	705,926	$ 701	1,364,846	1,800	(658,483)	(2,938)
Beginning balance (in shares) at Mar. 31, 2024		61,635
Beginning balance at Mar. 31, 2024	599,734	$ 617	1,144,468	(154)	(544,858)	(339)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	17,190		17,190
Exercise of stock options (in shares)		10
Exercise of stock options	140		140
Issuance of common stock under the Employee Stock Purchase Plan (in shares)		54
Issuance of common stock under the Employee Stock Purchase Plan	930	$ 1	929
Issuance of restricted stock units (in shares)		67
Issuance of restricted stock units	0	$ 1	(1)
Net unrealized gain (loss) on marketable debt securities	(498)			(498)
Net loss	(68,782)				(67,337)	(1,445)
Ending balance (in shares) at Jun. 30, 2024		61,766
Ending balance at Jun. 30, 2024	548,714	$ 619	1,162,726	(652)	(612,195)	(1,784)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	12,338		12,338
Exercise of stock options (in shares)		59
Exercise of stock options	685	$ 1	684
Issuance of restricted stock units (in shares)		44
Sale of common stock and pre-funded warrants, net of issuance cost (in shares)		8,094
Sale of common stock and pre-funded warrants, net of issuance cost	189,179	$ 81	189,098
Net unrealized gain (loss) on marketable debt securities	2,452			2,452
Net loss	(47,442)				(46,288)	(1,154)
Ending balance (in shares) at Sep. 30, 2024		69,963
Ending balance at Sep. 30, 2024	705,926	$ 701	1,364,846	1,800	(658,483)	(2,938)
Beginning balance (in shares) at Dec. 31, 2024		70,256
Beginning balance at Dec. 31, 2024	674,026	$ 703	1,381,607	(663)	(704,036)	(3,585)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	12,213		12,213
Exercise of stock options (in shares)		189
Exercise of stock options	2,974	$ 2	2,972
Issuance of restricted stock units (in shares)		691
Issuance of restricted stock units	0	$ 7	(7)
Net unrealized gain (loss) on marketable debt securities	1,018			1,018
Purchase of noncontrolling interest	(1,725)		(5,524)			3,799
Net loss	(48,632)				(48,418)	(214)
Ending balance (in shares) at Mar. 31, 2025		71,136
Ending balance at Mar. 31, 2025	639,874	$ 712	1,391,261	355	(752,454)	0
Beginning balance (in shares) at Dec. 31, 2024		70,256
Beginning balance at Dec. 31, 2024	674,026	$ 703	1,381,607	(663)	(704,036)	(3,585)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net unrealized gain (loss) on marketable debt securities	1,821
Net loss	(85,484)
Ending balance (in shares) at Sep. 30, 2025		71,343
Ending balance at Sep. 30, 2025	625,316	$ 714	1,412,750	1,158	(789,306)	0
Beginning balance (in shares) at Mar. 31, 2025		71,136
Beginning balance at Mar. 31, 2025	639,874	$ 712	1,391,261	355	(752,454)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	10,737		10,737
Issuance of common stock under the Employee Stock Purchase Plan (in shares)		80
Issuance of common stock under the Employee Stock Purchase Plan	662	$ 1	661
Issuance of restricted stock units (in shares)		81
Issuance of restricted stock units	0	$ 1	(1)
Net unrealized gain (loss) on marketable debt securities	(97)			(97)
Net loss	(30,825)				(30,825)
Ending balance (in shares) at Jun. 30, 2025		71,297
Ending balance at Jun. 30, 2025	620,351	$ 714	1,402,658	258	(783,279)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	10,092		10,092
Issuance of restricted stock units (in shares)		46
Net unrealized gain (loss) on marketable debt securities	900			900
Net loss	(6,027)				(6,027)
Ending balance (in shares) at Sep. 30, 2025		71,343
Ending balance at Sep. 30, 2025	$ 625,316	$ 714	$ 1,412,750	$ 1,158	$ (789,306)	$ 0

Xencor Inc 10-Q