Stock-Based Compensation Expense (Tables)

9 Months Ended

Sep. 30, 2022

Summary of Stock Option Activity

A summary of the stock option activity is presented below (in thousands, except per share amounts):

	Options Outstanding
	Number of Shares Subject to Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Balance at December 31, 2021		186		$	25.41		3.69	$	48.64
Options exercised		(2	)	$	15.21
Options canceled / forfeited / expired		(14	)	$	23.66
Balance at September 30, 2022		170		$	25.69		3.25		—
Vested and expected to vest at September 30, 2022		170		$	25.69		3.25		—
Balance at September 30, 2022		170		$	25.69		3.25		—

Summary of Restricted Stock Awards and Units

Information with respect to outstanding restricted stock awards and units (including both time-based vesting and performance-based vesting) as of September 30, 2022 is as follows (in thousands, except per share amounts):

	Restricted Stock and Restricted Stock Units
	Number of Shares Subject to Time- based Vesting			Number of Shares Subject to Performance- based Vesting		Total Number of Shares			Weighted Average Grant Date Fair Value Per Share
Balance at December 31, 2021		4,689			252		4,941		$	19.15
Employees transferred to IP Licensing business		(23	)		—		(23	)	$	17.31
Awards and units granted		3,080			141		3,221		$	16.59
Awards and units vested / earned		(1,447	)		—		(1,447	)	$	18.60
Awards and units canceled / forfeited		(496	)		—		(496	)	$	17.94
Balance at September 30, 2022		5,803			393		6,196		$	18.05

Summary of Stock-Based Compensation Expense

The following table summarizes the stock-based compensation expense attributable to the Company’s operations for the three and nine months ended September 30, 2022 and 2021 (in thousands):

	Three Months Ended September 30,						Nine Months Ended September 30,
	2022			2021			2022			2021
Cost of revenue, excluding depreciation and amortization of intangible assets	$	779		$	525		$	2,177		$	1,377
Research and development		5,515			4,604			16,295			12,808
Selling, general and administrative		4,291			2,991			11,289			10,178
Total stock-based compensation expense		10,585			8,120			29,761			24,363
Tax effect on stock-based compensation expense		(17	)		(55	)		(80	)		(163	)
Net effect on net loss	$	10,568		$	8,065		$	29,681		$	24,200

Stock-Based Compensation Expense Categorized by Equity Components

Stock-based compensation expense categorized by various equity components for the three and nine months ended September 30, 2022 and 2021 is summarized in the table below (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Restricted stock awards and units	$	10,001	$	7,244	$	27,370	$	21,892
Employee stock purchase plan		584		854		2,391		2,409
Employee stock options		—		22		—		62
Total stock-based compensation expense	$	10,585	$	8,120	$	29,761	$	24,363

Employee Stock Purchase Plan

Schedule of Assumptions Used to Value Awards Granted

The following assumptions were used to value the ESPP shares:

	March 2022			September 2021			March 2021
Expected life (years)		2.0			2.0			2.0
Risk-free interest rate		1.3	%		0.2	%		0.1	%
Dividend yield		1.1	%		0.9	%		1.2	%
Expected volatility		48.5	%		52.0	%		52.0	%

Restricted Stock Units

Schedule of Assumptions Used to Value Awards Granted

The following assumptions were used to value the restricted stock units subject to market conditions granted during the period:

	April 2022			March 2021
Expected life (years)		3.0			3.0
Risk-free interest rate		2.8	%		0.3	%
Dividend yield		1.2	%		1.0	%
Expected volatility		40.9	%		47.9	%