Stock-Based Compensation (Tables)

The following table summarizes stock-based compensation expense resulting from stock options, restricted stock units, market-based restricted stock units, performance-based restricted stock units, and the ESPP purchase rights included in our Condensed Consolidated Statements of Operations (in millions):


	Three Months Ended December 31,				Nine Months Ended December 31,
	2020		2019		2020		2019
Cost of revenue	$	1	$	1	$	4	$	3
Research and development	74		60		214		170
Marketing and sales	11		10		34		27
General and administrative	25		20		74		56
Stock-based compensation expense	$	111	$	91	$	326	$	256

The following table summarizes our stock option activity for the nine months ended December 31, 2020:


	Options (in thousands)	Weighted- Average Exercise Prices		Weighted- Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in millions)
Outstanding as of March 31, 2020	1,074	$	30.85
Granted	2	122.84
Exercised	(790)	29.34
Forfeited, cancelled or expired	—	—
Outstanding as of December 31, 2020	286	$	35.78	3.49	$	31
Vested and expected to vest	286	$	35.78	3.49	$	31
Exercisable as of December 31, 2020	286	$	35.78	3.49	$	31

The following table summarizes our restricted stock unit activity for the nine months ended December 31, 2020:


	Restricted Stock Rights (in thousands)	Weighted- Average Grant Date Fair Values
Outstanding as of March 31, 2020	6,217	$	100.42
Granted	3,080	126.46
Vested	(3,102)	103.39
Forfeited or cancelled	(345)	107.52
Outstanding as of December 31, 2020	5,850	$	112.14

The following table summarizes our performance-based restricted stock unit activity, presented with the maximum number of shares that could potentially vest, for the nine months ended December 31, 2020:


	Performance- Based Restricted Stock Units (in thousands)	Weighted- Average Grant Date Fair Value
Outstanding as of March 31, 2020	579	$	110.51
Granted	—	—
Forfeited or cancelled	—	—
Outstanding as of December 31, 2020	579	$	110.51

The following table summarizes our market-based restricted stock unit activity, presented with the maximum number of shares that could potentially vest, for the nine months ended December 31, 2020:


	Market-Based Restricted Stock Units (in thousands)	Weighted- Average Grant Date Fair Value
Outstanding as of March 31, 2020	1,898	$	128.41
Granted	874	145.78
Vested	(157)	113.72
Forfeited or cancelled	(420)	137.69
Outstanding as of December 31, 2020	2,195	$	134.60

The following table summarizes total shares repurchased during the three and nine months ended December 31, 2020 and 2019:


	May 2018 Program	November 2020 Program		Total
(In millions)			Shares	Amount		Shares	Amount		Shares	Amount
Three months ended December 31, 2020			—	$	—	2.5	$	326	2.5	$	326
Nine months ended December 31, 2020			0.7	$	78	2.5	$	326	3.2	$	404
Three months ended December 31, 2019			3.1	$	305	—	$	—	3.1	$	305
Nine months ended December 31, 2019			9.6	$	916	—	$	—	9.6	$	916