
	Three Months Ended March 31,
	2024		2023
Cost of revenue	$	173	$	227
Sales and marketing	2,832		3,618
Research and development	9,460		9,787
General and administrative	6,111		7,939
Total stock-based compensation	$	18,576	$	21,571

Under the Company’s 2021 Equity Incentive Plan, as of March 31, 2024, 30.8 million shares of Class A common stock were authorized, of which 17.3 million shares of Class A common stock were available for future issuance. The number of shares reserved for issuance was increased in January 2024 pursuant to the evergreen provisions set forth in the 2021 Equity Incentive Plan.

Under the Company’s 2021 Employee Stock Purchase Plan (the “ESPP”), as of March 31, 2024, 3.7 million shares of Class A common stock were authorized. The number of shares reserved for issuance was increased in January 2024 pursuant to the evergreen provisions set forth in the ESPP.

The ESPP provides for concurrent six-month offering and purchase periods beginning February 15 and August 15 of each year. During the three months ended March 31, 2024, 0.2 million shares of Class A common stock were purchased under the ESPP for an aggregate amount of $2.6 million. As of March 31, 2024, the Company recorded a liability of $0.7 million related to the accumulated payroll deductions, which are refundable to employees who withdraw from the ESPP. This amount is included within accrued expenses in the condensed consolidated balance sheets.

A summary of the Company’s stock option activity for the three months ended March 31, 2024 is as follows (in thousands, except weighted average information):


	Number of Options Outstanding	Weighted Average Exercise Price Per Share
Outstanding at December 31, 2023	5,159	$	2.27
Granted	—	—
Exercised	(170)	1.82
Forfeited/Canceled	(3)	2.00
Outstanding at March 31, 2024	4,986	$	2.29
Exercisable at March 31, 2024	4,939	$	2.29

As of March 31, 2024, total remaining stock-based compensation expense for unvested stock options is $0.8 million, which is expected to be recognized over a weighted average period of 0.5 years.

On April 19, 2021, the Company granted the CEO Performance Award, which provided for a grant of 1.4 million RSUs consisting of five vesting tranches with a vesting schedule based upon achieving stock price targets as well as satisfying certain minimum service requirements. On December 21, 2023, the Company entered into the Cancellation Agreement with the CEO, which provided for the cancellation of

the 1.4 million market-based RSUs included in the CEO Performance Award. As of the date of the Cancellation Agreement, none of the stock price targets set forth in the CEO Performance Award had been met and all of the RSUs were unvested. The cancellation resulted in an acceleration of $7.5 million in unrecognized stock-based compensation expense from future periods into the fourth quarter of 2023. Accordingly, the Company recorded no stock-based compensation expense related to the CEO Performance Award during the three months ended March 31, 2024. During the three months ended March 31, 2023, the Company recorded stock-based compensation expense of $1.5 million related to the CEO Performance Award.

For all RSUs, excluding the CEO Performance Award, the Company recorded stock-based compensation expense of $18.6 million and $19.2 million during the three months ended March 31, 2024 and 2023, respectively.

A summary of the Company’s RSU activity for the three months ended March 31, 2024 is as follows (in thousands, except weighted average information):


	Number of Shares	Weighted Average Grant Date Fair Value Per Share
Unvested at December 31, 2023	6,675	$	20.36
Granted	3,395	12.61
Vested	(988)	19.60
Forfeited/Canceled	(200)	20.52
Unvested at March 31, 2024	8,882	$	17.47