Stock-Based Compensation and Employee Benefit Plans

3 Months Ended

Mar. 31, 2023

Stock-Based Compensation and Employee Benefit Plans

Stock-Based Compensation Expense

The following table summarizes the components of stock-based compensation expense in the condensed consolidated statements of operations (in thousands):


	Three Months Ended March 31,
		2023		2022

Cost of revenue		$	4,161	$	3,860
Research and development		8,410		7,082
Sales and marketing		5,817		4,775
General and administrative		11,165		10,591
		$	29,553	$	26,308

Stock Option Activity

The following table summarizes the stock option activity under our stock plans during the reporting period:


	Outstanding Options
	Number of Shares	Weighted Average Exercise Price		Remaining Contractual Life (Years)	Aggregate Intrinsic Value
	(in thousands)
Balances at December 31, 2022	8,748,309	$	20.70	4.6	40,532

Exercised	(114,526)	6.71

Expired	(156,405)	30.45
Balances at March 31, 2023	8,477,378	20.71		4.4	42,208
Vested and expected to vest at March 31, 2023	8,474,492	20.71		4.4	42,171
Exercisable at March 31, 2023	8,417,352	$	20.81	4.4	41,425

Stock Options - During the three months ended March 31, 2023 and 2022, we recognized $0.2 million and $2.1 million of stock-based compensation costs for stock options, respectively.

We did not grant options in the three months ended March 31, 2023 and 2022.

As of March 31, 2023 and December 31, 2022, we had unrecognized compensation costs related to unvested stock options of $0.2 million and $0.4 million, respectively. This cost is expected to be recognized over the remaining weighted-average period of 1.0 year and 0.9 years, respectively. Cash received from stock options exercised totaled $0.8 million and $1.0 million for the three months ended March 31, 2023 and 2022, respectively.

Stock Award Activity

A summary of our stock awards activity and related information is as follows:


	Number of Awards Outstanding	Weighted Average Grant Date Fair Value

Unvested Balance at December 31, 2022	9,549,035	$	19.99
Granted	4,115,300	18.99
Vested	(2,104,904)	17.81
Forfeited	(126,807)	28.80
Unvested Balance at March 31, 2023	11,432,624	$	19.93

Stock Awards - The estimated fair value of RSUs and PSUs is based on the fair value of our Class A common stock on the date of grant. For the three months ended March 31, 2023 and 2022, we recognized $22.6 million and $21.0 million of stock-based compensation costs for stock awards, respectively.

As of March 31, 2023 and December 31, 2022, we had $187.0 million and $135.7 million of unrecognized stock-based compensation expense related to unvested stock awards, expected to be recognized over a weighted average period of 2.2 years and 1.9 years, respectively.

Executive Awards

On February 15, 2023, the Company granted RSU and PSU awards (the “2023 Executive Awards”) to certain executive staff pursuant to the 2018 Plan. The RSUs have time-based vesting schedules, started vesting on February 15, 2023 and shall vest over a three year period. PSUs started vesting on February 15, 2023 and have a three-year cliff vesting period. PSUs will vest based on a combination of time and achievement against performance metrics targets assuming continued employment and service through each vesting date. Stock-based compensation costs associated with the 2023 Executive Awards are recognized over the service period as we evaluate the probability of the achievement of the performance conditions.

The following table presents the stock activity and the total number of shares available for grant under our stock plans:


						Plan Shares Available for Grant

Balances at December 31, 2022						28,340,641
Added to plan						8,948,255
Granted						(3,851,435)

Cancelled/Forfeited						223,447
Expired						(138,839)
Balances at March 31, 2023						33,522,069

2018 Employee Stock Purchase Plan

During the three months ended March 31, 2023 and 2022, we recognized $6.5 million and $2.5 million of stock-based compensation costs for the 2018 ESPP, respectively. We issued 449,525 and 420,689 shares in the three months ended March 31, 2023 and 2022, respectively. During the three months ended March 31, 2023 and 2022, we added an additional 2,239,563 and 2,055,792 shares and there were 15,630,754 and 13,840,716 shares available for issuance as of March 31, 2023 and December 31, 2022, respectively.

As of March 31, 2023 and December 31, 2022, we had $21.3 million and $12.0 million of unrecognized stock-based compensation costs, expected to be recognized over a weighted average period of 0.9 years and 0.6 years, respectively.