Equity Incentive Plans (Tables)

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Summary of Changes in Shares Available for Grant

Changes in shares available for grant during the three months ended March 31, 2024 were as follows:

	Shares Available for Grant
Shares available for grant at December 31, 2023		15,299,763
2019 Equity Incentive Plan reserve increase effective January 1, 2024		7,254,113
Stock options and restricted stock units granted and the maximum market-based restricted stock units granted eligible to be earned		(8,399,478	)
Stock options and restricted stock units forfeited or expired		995,588
Shares available for grant at March 31, 2024		15,149,986

Summary of Stock Option Activity Under 2009 Plan and 2019 Plan

Stock option activity under the 2009 Plan and 2019 Plan during the three months ended March 31, 2024 was as follows:

	Shares Subject to Outstanding Stock Options			Weighted-Average Exercise Price per Share		Aggregate Intrinsic Value (in thousands)
Stock options outstanding at December 31, 2023		12,875,045		$	15.90
Stock options granted		1,008,364			3.99
Stock options forfeited		(195,745	)		17.55
Stock options expired		(67,952	)		17.31
Stock options exercised		(30,900	)		1.43
Stock options outstanding at March 31, 2024		13,588,812		$	15.02	$	108
Stock options vested and exercisable at March 31, 2024		9,662,208		$	16.25	$	108

Summary of Restricted Stock Unit Activity

Restricted stock unit activity under the 2019 Plan during the three months ended March 31, 2024 was as follows:

	Restricted Stock Units Outstanding			Weighted-Average Grant Date Fair Value per Share
Nonvested restricted stock units outstanding at December 31, 2023		9,669,460		$	10.32
Restricted stock units granted		5,327,094			3.99
Restricted stock units forfeited		(731,891	)		10.05
Restricted stock units vested		(2,255,158	)		11.04
Nonvested restricted stock units outstanding at March 31, 2024		12,009,505		$	7.39

Summary of Estimated Grant Date Fair Values of Stock Options Granted

The estimated grant date fair values of stock options granted during the three months ended March 31, 2024 and 2023 were estimated using the Black-Scholes option-pricing model with the following assumptions:

	Three Months Ended March 31,
	2024	2023
Fair value of common stock	$3.99	$8.46
Expected term (in years)	5.27 - 6.08	5.27 - 6.08
Risk-free interest rate	4.2%	4.2% - 4.3%
Expected volatility	74.5% - 75.0%	71.2% - 71.6%
Expected dividend yield	—	—

Summary of Compensation Costs Related to Stock Options and RSUs Included on Unaudited Condensed Consolidated Statements of Operations

The compensation cost related to stock options, restricted stock units and market-based restricted stock units for the three months ended March 31, 2024 and 2023 are included on the unaudited condensed consolidated statements of operations as follows (in thousands):

	Three Months Ended March 31,
	2024		2023
Cost of revenue	$	906	$	1,294
Research and development		4,684		4,549
Sales and marketing		3,013		3,431
General and administrative		5,695		5,397
Total share-based compensation expense	$	14,298	$	14,671

Schedule of Unrecognized Share-Based Compensation Expense and the Remaining Weighted-Average Recognition Period

As of March 31, 2024, unrecognized share-based compensation expense and the remaining weighted-average recognition period were as follows:

	Unrecognized Share-Based Compensation Expense (in thousands)		Remaining Weighted-Average Recognition Period (in years)
Nonvested stock options	$	28,766		1.92
Nonvested restricted stock units		83,591		2.79
Nonvested market-based restricted stock units		14,271		2.28