Stock-Based Compensation (Tables)
|
12 Months Ended |
Dec. 31, 2023 |
|---|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| Summary of Shares of Common Stock Available for Issuance |
Shares of common stock available for issuance under the Company’s equity incentive plans at December 31, 2023 were as follows:
|
|
|
|
|
|
|
December 31, 2023 |
|
Outstanding stock awards |
|
|
7,059,412 |
|
Reserved for future award grants |
|
|
5,239,303 |
|
Reserved for future ESPP |
|
|
83,756 |
|
Total common stock reserved for stock awards |
|
|
12,382,471 |
|
|
| Summary of Stock Option Activity |
A summary of the Company’s stock option activity (excluding performance-based stock option activity summarized further below) for the years ended December 31, 2023, 2022, and 2021 is as follows:
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Outstanding Options |
|
(in thousands, except share and per share data) |
|
Number of
Shares |
|
|
Weighted-
Average
Exercise Price |
|
|
Weighted-
Average
Remaining
Contractual
Term (in years) |
|
|
Aggregate
Intrinsic
Value |
|
Balance—December 31, 2020 |
|
|
4,948,306 |
|
|
$ |
7.10 |
|
|
|
6.71 |
|
|
$ |
146,044 |
|
Options granted |
|
|
1,026,276 |
|
|
|
21.26 |
|
|
|
|
|
|
|
Options exercised |
|
|
(862,056 |
) |
|
|
2.43 |
|
|
|
|
|
|
|
Options forfeited or expired |
|
|
(110,107 |
) |
|
|
13.88 |
|
|
|
|
|
|
|
Balance—December 31, 2021 |
|
|
5,002,419 |
|
|
$ |
10.66 |
|
|
|
6.89 |
|
|
$ |
28,308 |
|
Options granted |
|
|
1,429,295 |
|
|
|
4.80 |
|
|
|
|
|
|
|
Options exercised |
|
|
(488,187 |
) |
|
|
2.07 |
|
|
|
|
|
|
|
Options forfeited or expired |
|
|
(492,395 |
) |
|
|
10.57 |
|
|
|
|
|
|
|
Balance—December 31, 2022 |
|
|
5,451,132 |
|
|
$ |
9.90 |
|
|
|
5.31 |
|
|
$ |
7 |
|
Options granted |
|
|
2,638,500 |
|
|
|
2.61 |
|
|
|
|
|
|
|
Options exercised |
|
|
(8 |
) |
|
|
2.44 |
|
|
|
|
|
|
|
Options forfeited or expired |
|
|
(2,284,038 |
) |
|
|
7.84 |
|
|
|
|
|
|
|
Balance—December 31, 2023 |
|
|
5,805,586 |
|
|
$ |
7.40 |
|
|
|
6.90 |
|
|
$ |
64 |
|
Options vested and exercisable as of December 31, 2023 |
|
|
3,103,913 |
|
|
$ |
9.69 |
|
|
|
5.57 |
|
|
$ |
1 |
|
|
| Summary of Weighted-average Assumptions Used in Determination of Fair Value of Stock Options |
air value of stock options is recognized as compensation expense on a straight-line basis over the requisite service periods of the awards. Fair value of stock options was estimated using the following range of assumptions:
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|
|
|
|
|
|
|
Year Ended December 31, |
|
|
2023 |
|
2022 |
|
2021 |
Expected term (in years) |
|
5.50 - 6.08 |
|
5.50 - 6.08 |
|
5.50 - 6.27 |
Volatility |
|
78.47 - 79.31% |
|
68.37 - 77.68% |
|
67.97 - 69.90% |
Risk-free interest rate |
|
3.47 - 4.66% |
|
1.62 - 4.23% |
|
0.62 - 1.39% |
Dividend yield |
|
–% |
|
–% |
|
–% |
|
| Summary of Restricted Stock Units Activity |
A summary of the Company’s RSU activity for the years ended December 31, 2023, 2022 and 2021 is as follows:
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|
|
|
|
|
|
|
|
|
|
|
|
|
Unvested Restricted Stock Units |
|
(in thousands, except share and per share data) |
|
Number of
Shares |
|
|
Weighted-
Average
Grant Date
Fair Value |
|
|
Aggregate
Fair Value |
|
Balance—December 31, 2020 |
|
|
619,218 |
|
|
$ |
10.41 |
|
|
$ |
22,670 |
|
RSUs granted |
|
|
1,387,656 |
|
|
|
18.05 |
|
|
|
|
RSUs vested |
|
|
(266,119 |
) |
|
|
10.93 |
|
|
|
5,521 |
|
RSUs forfeited |
|
|
(61,059 |
) |
|
|
18.45 |
|
|
|
|
Balance—December 31, 2021 |
|
|
1,679,696 |
|
|
$ |
16.35 |
|
|
$ |
23,969 |
|
RSUs granted |
|
|
2,071,201 |
|
|
|
4.86 |
|
|
|
|
RSUs vested |
|
|
(897,871 |
) |
|
|
11.74 |
|
|
|
3,189 |
|
RSUs forfeited |
|
|
(231,544 |
) |
|
|
10.94 |
|
|
|
|
Balance—December 31, 2022 |
|
|
2,621,482 |
|
|
$ |
9.33 |
|
|
$ |
5,191 |
|
RSUs granted |
|
|
24,500 |
|
|
|
2.18 |
|
|
|
|
RSUs vested |
|
|
(839,194 |
) |
|
|
9.91 |
|
|
|
1,520 |
|
RSUs forfeited |
|
|
(552,962 |
) |
|
|
8.89 |
|
|
|
|
Balance—December 31, 2023 |
|
|
1,253,826 |
|
|
$ |
8.99 |
|
|
$ |
2,633 |
|
|
| Stock Based Compensation Expense by Award Type and Function |
The following is a summary of stock-based compensation expense by function (in thousands):
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Year Ended December 31, |
|
|
|
2023 |
|
|
2022 |
|
|
2021 |
|
Cost of revenue |
|
$ |
1,761 |
|
|
$ |
1,922 |
|
|
$ |
1,414 |
|
Research and development |
|
|
4,870 |
|
|
|
5,256 |
|
|
|
4,064 |
|
Selling, general and administrative |
|
|
7,420 |
|
|
|
12,255 |
|
|
|
8,900 |
|
Total stock-based compensation expense |
|
$ |
14,051 |
|
|
$ |
19,433 |
|
|
$ |
14,378 |
|
The following is a summary of stock-based compensation expense by award type (in thousands):
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Year Ended December 31, |
|
|
|
2023 |
|
|
2022 |
|
|
2021 |
|
Stock options |
|
$ |
5,746 |
|
|
$ |
8,560 |
|
|
$ |
8,585 |
|
RSUs |
|
|
7,539 |
|
|
|
9,990 |
|
|
|
4,765 |
|
ESPP |
|
|
766 |
|
|
|
883 |
|
|
|
1,028 |
|
Total stock-based compensation expense |
|
$ |
14,051 |
|
|
$ |
19,433 |
|
|
$ |
14,378 |
|
|
| 2019 Employee Stock Purchase Plan |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| Summary of Weighted-average Assumptions Used to Calculate Stock-Based Compensation For Each Stock Purchase Right Granted Under ESPP |
:
|
|
|
|
|
|
|
|
|
Year Ended December 31, |
|
|
2023 |
|
2022 |
|
2021 |
Expected term (in years) |
|
0.5 |
|
0.49 - 0.5 |
|
0.49 |
Volatility |
|
69.23 - 84.88% |
|
82.35 - 112.07% |
|
55.92 - 74.88% |
Risk-free interest rate |
|
5.14 - 5.51% |
|
1.49 - 4.58% |
|
0.04 - 0.06% |
Dividend yield |
|
–% |
|
–% |
|
–% |
Fair value |
|
$0.33 - $0.91 |
|
$1.26 - $2.23 |
|
$6.30 - $8.21 |
|
| Performance-Based Stock Option | 2019 Plan |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
|
| Summary of Stock Option Activity |
A summary of the Company’s performance-based stock option activity for the years ended December 31, 2023, 2022 and 2021 is as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Outstanding Performance-Based Options |
|
(in thousands, except share and per share data) |
|
Number of
Shares |
|
|
Weighted-
Average
Exercise Price |
|
|
Weighted-
Average
Remaining
Contractual
Term (in
years) |
|
|
Aggregate
Intrinsic
Value |
|
Balance—December 31, 2020 |
|
|
421,000 |
|
|
$ |
5.10 |
|
|
|
9.21 |
|
|
$ |
13,266 |
|
No activities |
|
|
— |
|
|
|
|
|
|
|
|
|
|
Balance—December 31, 2021 |
|
|
421,000 |
|
|
$ |
5.10 |
|
|
|
8.21 |
|
|
$ |
3,861 |
|
No activities |
|
|
— |
|
|
|
|
|
|
|
|
|
|
Balance—December 31, 2022 |
|
|
421,000 |
|
|
$ |
5.10 |
|
|
|
1.00 |
|
|
$ |
— |
|
Options expired |
|
|
(421,000 |
) |
|
|
5.10 |
|
|
|
|
|
|
|
Balance—December 31, 2023 |
|
|
— |
|
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