Net Loss per Share Attributable to Cullinan (Tables)

6 Months Ended

Jun. 30, 2025

Earnings Per Share [Abstract]

Summary of Calculation of Basic and Diluted Net Loss Per Share

The following tables set forth the calculation of basic and diluted net loss per share attributable to Cullinan for the three and six months ended June 30, 2025 and 2024 (in thousands, except per share data):


		Three Months Ended June 30,
		2025								2024
		Common Stock				Preferred Stock				Common Stock				Preferred Stock
Numerator:
Net loss attributable to Cullinan - basic and diluted		$	(63,127	)		$	(6,928	)		$	(37,605	)		$	(4,423	)
Denominator:
Weighted-average shares outstanding — basic and diluted			59,015				648				55,052				648
Net loss per share attributable to Cullinan:
Basic and diluted		$	(1.07	)		$	(10.70	)		$	(0.68	)		$	(6.83	)


		Six Months Ended June 30,
		2025								2024
		Common Stock				Preferred Stock				Common Stock				Preferred Stock
Numerator:
Net loss attributable to Cullinan - basic and diluted		$	(106,825	)		$	(11,731	)		$	(69,940	)		$	(9,236	)
Denominator:
Weighted-average shares outstanding — basic and diluted			58,960				648				49,031				648
Net loss per share attributable to Cullinan:
Basic and diluted		$	(1.81	)		$	(18.12	)		$	(1.43	)		$	(14.26	)

Cullinan used the treasury stock method for equity awards and the if converted method for preferred stock to determine the number of dilutive shares outstanding in each period.

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 diluted weighted-average common shares outstanding for the six months ended June 30, 2025 and 2024 because their effect would have been anti-dilutive (in thousands):


		Six Months Ended June 30,
		2025				2024
Stock options			12,601				8,289
Preferred stock			6,475				6,475
Restricted stock units			1,609				301
Employee stock purchase plan			10				7
Total			20,695				15,072