Net Income (Loss) per Share (Tables)

6 Months Ended

Jun. 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 for the three and six months ended June 30, 2023 and 2022:

	Three Months Ended June 30,					Six Months Ended June 30,
	2023			2022		2023			2022
	(in thousands, except per share data)
Numerator:
Net income (loss) attributable to common stockholders of Cullinan	$	(32,214	)	$	174,898	$	(90,176	)	$	162,800
Denominator:
Weighted-average common stock outstanding - basic		39,952			44,873		40,315			44,654
Dilutive effect of common stock issuable from assumed exercise of equity awards		—			1,508		—			1,735
Weighted-average common stock outstanding - diluted		39,952			46,381		40,315			46,389
Net income (loss) per share:
Basic	$	(0.82	)	$	3.90	$	(2.24	)	$	3.65
Diluted	$	(0.82	)	$	3.77	$	(2.24	)	$	3.51

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 for the six months ended June 30, 2023 and 2022 because their effect would have been anti-dilutive:

	Six Months Ended June 30,
	2023		2022
	(in thousands)
Stock options		9,185		6,250
Preferred stock		5,795		—
Restricted stock awards and RSUs		156		—
Total		15,136		6,250