Earnings per Share (Tables)

9 Months Ended

Sep. 30, 2022

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 earnings (net loss) per share:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2022			2021			2022		2021
	(in thousands, except per share data)
Numerator:
Net income (loss) attributable to common stockholders of Cullinan	$	(24,804	)	$	(17,350	)	$	137,996	$	(33,056	)
Denominator:
Weighted-average common stock outstanding - basic		45,611			43,439			44,966		43,254
Dilutive effect of common stock issuable from assumed exercise of equity awards		—			—			1,614		—
Weighted-average common stock outstanding - diluted		45,611			43,439			46,580		43,254
Earnings (net loss) per share:
Basic	$	(0.54	)	$	(0.40	)	$	3.07	$	(0.76	)
Diluted	$	(0.54	)	$	(0.40	)	$	2.96	$	(0.76	)

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 the diluted net income (loss) per share for the periods presented because their effect would have been anti-dilutive:

	As of September 30,
	2022		2021
	(in thousands)
Stock options		6,643		7,200
Restricted stock units		24		132
Employee Stock Purchase Plan		12		2
Total		6,679		7,334