Net Income (Loss) per Share (Tables)

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Summary of Calculation of Basic and Diluted Net Loss Per Share

The following table sets forth the calculation of basic and diluted net income (loss) per share attributable to common stockholders of Cullinan for the three and nine months ended September 30, 2023 and 2022:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2023			2022			2023			2022
	(in thousands, except per share data)
Numerator:
Net income (loss) attributable to common stockholders of Cullinan	$	(39,183	)	$	(24,804	)	$	(129,359	)	$	137,996
Denominator:
Weighted-average common stock outstanding - basic		42,734			45,611			41,130			44,966
Dilutive effect of common stock issuable from assumed exercise of equity awards		—			—			—			1,614
Weighted-average common stock outstanding - diluted		42,734			45,611			41,130			46,580
Net income (loss) per share attributable to common stockholders of Cullinan:
Basic	$	(0.91	)	$	(0.54	)	$	(3.15	)	$	3.07
Diluted	$	(0.91	)	$	(0.54	)	$	(3.15	)	$	2.96

Summary of Outstanding Equity Instruments Excluded from Computation of Diluted Net Income (Loss) Per Share

The following table sets forth potential common shares that were excluded from the computation of diluted net income (loss) per share attributable to common stockholders of Cullinan for the nine months ended September 30, 2023 and 2022 because their effect would have been anti-dilutive:

	Nine Months Ended September 30,
	2023		2022
	(in thousands)
Stock options		9,355		6,643
Preferred stock		6,024		—
Restricted stock awards and RSUs		158		24
Employee stock purchase plan		1		12
Total		15,538		6,679