Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Tables)

v3.21.2
Stock-Based Compensation (Tables)
 9 Months Ended
Sep. 30, 2021
Share-based Payment Arrangement [Abstract]  
Stock-Based Compensation Expense The Company recognizes stock-based compensation in the consolidated statements of operations, based on the department to which the related employee reports, as follows:
Three Months Ended September 30, Nine Months Ended September 30,
2021 2020 2021 2020
(in thousands) (in thousands)
Cost of net revenue $ 151  $ 143  $ 468  $ 417 
Research and development 7,692  6,056  22,121  14,842 
Selling, general and administrative 8,179  7,350  20,354  17,202 
Restructuring expense —  596  —  596 
$ 16,022  $ 14,145  $ 42,943  $ 33,057 
Summary of Restricted Stock Unit Activity A summary of the Company’s restricted stock unit activity is as follows:
Number of Shares
(in thousands)		 Weighted-Average Grant-Date Fair Value per Share
Outstanding at December 31, 2020 5,832  $ 20.05 
  Granted 2,115  37.66 
  Vested (1,951) 26.48 
  Canceled (567) 23.86 
Outstanding at September 30, 2021 5,429  $ 24.20 
Summary of Performance-Based Restricted Stock Unit Activity
A summary of the Company’s performance-based restricted stock unit activity is as follows:
Number of Shares
(in thousands)		 Weighted-Average Grant-Date Fair Value per Share
Outstanding at December 31, 2020 1,722  $ 13.97 
  Granted(1)
599  35.10 
  Vested (311) 16.74 
  Canceled (5) 35.72 
Outstanding at September 30, 2021 2,005  $ 19.80 
________________
(1) Number of shares granted is based on the maximum percentage achievable in the performance-based restricted stock unit award.
Employee Stock Purchase Plan, Valuation Assumptions The fair values of employee stock purchase rights were estimated using the Black-Scholes option pricing model at their respective grant date using the following assumptions:
Nine Months Ended September 30,
2021 2020
Weighted-average grant date fair value per share $ 10.85  $ 6.41 
Risk-free interest rate 0.04  % 0.15  %
Dividend yield —  % —  %
Expected life (in years) 0.50 0.51
Volatility 61.10  % 93.25  %
Summary of Stock Option Activity A summary of the Company’s stock options activity is as follows:
Number of Options
(in thousands)		 Weighted-Average Exercise Price Weighted-Average Contractual Term (in years) Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2020 797  $ 14.67 
Exercised (370) 12.00 
Outstanding at September 30, 2021 427  $ 16.97  3.50 $ 13,799 
Vested and expected to vest at September 30, 2021 427  $ 16.97  3.49 $ 13,799 
Exercisable at September 30, 2021 358  $ 16.69  3.43 $ 11,646