Net Loss per Share (Tables)

9 Months Ended

Sep. 30, 2021

Summary of Calculation of Basic and Diluted Net Loss Per Share

The following table sets forth the calculation of basic and diluted net loss per share:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2020			2021			2020 ⁽¹⁾			2021
	(in thousands, except share and per share data)						(in thousands, except share and per share data)
Numerator:
Net loss attributable to common stockholders of Cullinan	$	(9,858	)	$	(17,350	)	$	(23,453	)	$	(33,056	)
Denominator
Total weighted-average shares used in computing net loss per share, basic and diluted		19,721,992			43,438,861			19,453,479			43,254,230
Net Loss per Share:	$	(0.50	)	$	(0.40	)	$	(1.21	)	$	(0.76	)

(1) The shares and per share amounts for the nine months ended September 30, 2020 were derived from the unaudited consolidated financial statements as of that date and were retroactively adjusted as a result of the Reorganization and Reverse Stock Split. See Note 3 to the for additional details.

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

The following outstanding equity instruments were excluded from the computation of the diluted net loss per share for the periods presented because their effect would have been anti-dilutive:

	As of September 30,
	2020		2021
Restricted stock awards		274,357		131,812
Stock options		—		7,200,268
Estimated shares issuable under the ESPP		—		2,234
Total		274,357		7,334,314