Stock-Based Awards

9 Months Ended

Sep. 30, 2020

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Awards

Note 4. Stock-Based Awards

Stock Options

The following table summarizes stock option activity for the nine months ended September 30, 2020 (in thousands):

	Number of Underlying Shares
Outstanding at December 31, 2019		3,262
Granted		649
Exercised		(326	)
Forfeited or expired		(166	)
Outstanding at September 30, 2020		3,419
Vested and exercisable at September 30, 2020		1,647

Restricted Stock Units

The following table summarizes activity for restricted stock units, or RSUs, and RSUs with performance conditions, or PSUs, for the nine months ended September 30, 2020 (in thousands):

	Number of Underlying Shares
	RSUs			PSUs
Outstanding at December 31, 2019		509			252
Granted		543			241
Vested		(120	)		(243	)
Forfeited		(46	)		(9	)
Outstanding at September 30, 2020		886			241

We granted PSUs in 2019 and 2020 under our annual bonus program to our senior executives and other bonus-eligible employees. The number of annual PSUs that ultimately vest depends on us attaining a financial metric for the fiscal year as well as on the employee’s continued employment through the vesting date. The compensation committee and board of directors certified achievement of the financial metric for PSUs granted in 2019, vesting 243,000 shares in first-quarter 2020.  

Stock-Based Compensation Expense

The following table presents stock-based compensation expense included in our condensed consolidated statements of operations for the periods presented (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Cost of revenue	$	212	$	192	$	595	$	495
Research and development expense		2,088		1,717		5,749		4,028
Sales and marketing expense		1,451		1,622		4,023		4,028
General and administrative expense		1,932		1,262		5,134		3,262
Total stock-based compensation expense	$	5,683	$	4,793	$	15,501	$	11,813