Equity Incentive Plans (Tables)

3 Months Ended

Mar. 31, 2026

Total stock-based compensation expense by function was as follows (in millions):


	Three Months Ended March 31,
	2026		2025

Research and development	$	36	$	29
Selling, general, and administrative	10		5
Total	$	46	$	34

RSU activity under the Plan and the 2017 Plan was as follows (in millions, except per share amounts):


	Number of shares	Weighted- average grant date fair value
Unvested at December 31, 2025	80	$	5.12
Granted	63	4.41
Vested	(10)	4.39
Forfeited	(3)	5.21
Unvested at March 31, 2026	130	$	4.83

Stock options granted under the Plan during the three months ended March 31, 2026 were as follows:


	Three Months Ended March 31, 2026

Stock options granted (in millions)	1
Weighted average grant date fair value	$	3.18
Weighted average grant date fair value assumptions:
Expected term	6.5 years
Risk-free interest rates	4.1		%

Expected volatility	79.1		%

Stock option activity under the Plan and the 2017 Plan was as follows (in millions, except per share amounts):


	Number of shares	Weighted average exercise price		Weighted average remaining contractual term (in years)	Aggregate intrinsic value
Outstanding at December 31, 2025	91	$	2.21
Granted	1	4.38
Exercised	(4)	1.85
Forfeited	(1)	3.18

Outstanding at March 31, 2026	87	$	2.23	6.5	$	155
Exercisable at March 31, 2026	62	$	1.98	5.9	$	121