In July 2018, the Board adopted the 2018 Equity Incentive Plan (the “2018 Plan”). The 2018 Plan became effective in connection with the Company's initial public offering ("IPO"). The number of shares reserved for issuance under the 2018 Plan increases automatically on January 1 of each year beginning in 2019 and continuing through 2028 by a number of shares of common stock equal to the lesser of (x) 5% of the total outstanding shares of the Company’s common stock and common stock equivalents as of the immediately preceding December 31 (rounded to the nearest whole share) and (y) a number of shares determined by the Company's the Board.

Pursuant to the 2018 Plan, the Company issues stock options to employees and directors. The fair value of the stock options is based on the Company’s closing stock price on the trading day immediately prior to the date of grant. The option price, number of shares, and grant date are determined at the discretion of the Board. For so long as the option holder performs services for the Company, the options generally vest over 48 months, on a monthly or quarterly basis, with certain options subject to an initial annual cliff vest, and are exercisable for a period not to exceed ten years from the date of grant.

The summary of the Company’s stock option activity is as follows:


	Number of Options			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
						(In years)		(In thousands)
Outstanding at October 2, 2021		14,545,239		$	12.86		5.1	$	282,141
Granted		—			—
Exercised		(2,526,447	)		11.59
Expired		(340	)		2.50
Forfeited		(18,072	)		15.05
Outstanding at April 2, 2022		12,000,380		$	13.13		4.9	$	174,640
At April 2, 2022
Options exercisable		11,234,842		$	13.06		4.7	$	164,249
Options vested and expected to vest		11,940,890		$	13.12		4.9	$	173,829

As of April 2, 2022, and October 2, 2021, the Company had $2.5 million and $6.2 million, respectively, of unrecognized stock-based compensation expense related to stock options, which are expected to be recognized over weighted-average periods of 0.7 and 0.9 years, respectively.

Pursuant to the 2018 Plan, the Company issues RSUs to employees and directors. The fair value of RSUs is based on the Company's closing stock price on the trading day immediately preceding the date of grant. RSUs vest quarterly over the service period, which is generally four years, with certain awards subject to an initial annual cliff vest. The summary of the Company’s RSU activity is as follows:


	Number of Units			Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value
						(In thousands)
Outstanding at October 2, 2021		9,283,525		$	12.64	$	299,487
Granted		2,958,133			32.04
Released		(2,004,895	)		13.47
Forfeited		(512,347	)		17.55
Outstanding at April 2, 2022		9,724,416		$	18.11	$	269,172
At April 2, 2022
Units expected to vest		8,328,841		$	17.73	$	230,542

As of April 2, 2022, and October 2, 2021, the Company had $134.5 million and $90.0 million of unrecognized stock-based compensation expense related to RSUs, which are expected to be recognized over weighted-average periods of 2.7 and 2.5 years, respectively.

Pursuant to the 2018 Plan, the Company issues PSUs that vest on the satisfaction of service and performance conditions. The Company estimates the fair value of PSUs on the grant date and recognizes compensation expense in the period it becomes probable that performance conditions will be achieved. On a quarterly basis, the Company re-evaluates the assumption of the probability that performance conditions will be satisfied and revises its estimates

as appropriate as new or updated information becomes available. The summary of the Company’s PSU activity is as follows:


	Number of Units		Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value
					(In thousands)
Outstanding at October 2, 2021		158,521	$	22.81	$	5,114
Granted		252,296		29.71
Vested		—		—
Forfeited		—		—
Outstanding at April 2, 2022		410,817	$	27.05	$	11,371

As of April 2, 2022, and October 2, 2021, the Company had $6.8 million and $3.6 million of unrecognized stock-based compensation expense related to PSUs, which are expected to be recognized over weighted-average periods of 1.1 and 1.2 years, respectively.

Total stock-based compensation expense by functional category was as follows:


	Three Months Ended				Six Months Ended
	April 2, 2022		April 3, 2021		April 2, 2022		April 3, 2021
(In thousands)
Cost of revenue	$	377	$	261	$	705	$	474
Research and development		8,091		6,683		14,829		12,942
Sales and marketing		4,177		3,632		7,824		7,040
General and administrative		8,580		5,787		15,326		10,751
Total stock-based compensation expense	$	21,225	$	16,363	$	38,684	$	31,207