EQUITY AWARD PLANS (Tables)

12 Months Ended

Jul. 31, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

The Company’s summary of RSU activity under the Stock Plans is as follows:



	Number of Shares		Grant Date Fair Value per Share
Outstanding—July 31, 2016	12,265,369		$	13.23
Granted	12,986,597		$	21.84
Released	(6,146,169	)	$	15.63
Canceled/forfeited	(1,729,707	)	$	13.57
Outstanding—July 31, 2017	17,376,090		$	18.85

Schedule of Employee Stock Purchase Plan, Valuation Assumptions

The Company uses the Black-Scholes option-pricing model to determine the fair value of shares purchased under the 2016 ESPP with the following weighted-average assumptions on the date of grant (on October 11, 2016 and April 5, 2017):



	Fiscal Year Ended July 31, 2017
Expected term (in years)	0.75
Risk-free interest rate	0.6	%
Volatility	51.0	%
Dividend yield	—	%

Schedule of Stock Option Activity

The Company’s stock option activity under the Stock Plan is as follows:



	Options Outstanding
	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value
						(In years)	(In thousands)
Outstanding—August 1, 2016	26,166,968		(1)	$	4.39	7.5	$	208,101
Options granted	1,047,950			12.14
Options exercised	(4,786,381	)		3.27
Options canceled/forfeited	(2,094,006	)		8.89
Outstanding—July 31, 2017	20,334,531			4.59		6.4	338,787
Exercisable—July 31, 2017	19,645,676			4.43		6.3	330,486
Vested and expected to vest—July 31, 2017	20,334,531			4.59		6.4	338,787

(1)

Includes 455,000 stock options with both service and performance conditions with a weighted-average fair value per share of $3.78 (the “Performance Stock Options”). Vesting of the Performance Stock Options was subject to continuous service with the Company (the “service condition”) and satisfaction of certain liquidity events of the Company (the “performance condition”). The Company recognized cumulative stock-based compensation expense related to the Performance Stock Options in the first quarter of fiscal year 2017 as the performance condition was met upon the Company's successful IPO. The cumulative stock-based compensation expense recorded in the first quarter of fiscal 2017 was for the portion of the awards for which the relevant service condition had been satisfied and the remaining expense is being recognized over the remaining service period.

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

Stock-Based Compensation—Total stock-based compensation expense recognized for stock awards granted under the equity award plans in the consolidated statements of operations is as follows (in thousands):



	Fiscal Year Ended July 31,
	2015		2016		2017
Cost of revenue:
Product	$	363	$	391	$	3,066
Support and other services	718		968		10,411
Sales and marketing	6,474		8,006		78,117
Research and development	5,411		6,259		109,044
General and administrative	4,174		4,432		30,853
Total stock-based compensation expense	$	17,140	$	20,056	$	231,491

Schedule Stock Option Valuation Assumptions

The fair value of the Company’s stock options was estimated using the following weighted-average assumptions:



	Fiscal Year Ended July 31,
	2015			2016			2017
Fair value of common stock	$	10.29		$	14.81		$	12.14
Expected term (in years)	6.1			6.1			6.1
Risk-free interest rate	1.7		%	1.6		%	1.3		%
Volatility	46		%	42		%	52		%
Dividend yield	—			—			—