XML 57 R20.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Equity-based Compensation | 12 Months Ended
--- | ---
Dec. 31, 2021
Share-based Payment Arrangement [Abstract] |
Equity-based Compensation | 11. Equity-based Compensation Option and Grant Plans In April 2015, the Company’s shareholders approved the 2015 Stock Option and Grant Plan, or the 2015 Plan, and in July 2016, the Company’s shareholders approved the 2016 Stock Option and Incentive Plan, or the 2016 Plan. In May 2018, the Company’s shareholders approved the 2018 Stock Option and Incentive Plan, or the 2018 Plan (collectively, the “Plans”). Subsequent to the IPO, no further options were granted under the 2015 Plan. The Plans provide for the issuance of equity awards in the form of restricted shares, options to purchase common shares which may constitute incentive stock options, or ISOs, or non-statutory stock options, or NSOs, unrestricted stock unit grants, and qualified performance and market-based awards to eligible employees, officers, directors, non-employee consultants and other key personnel. Terms of the equity awards, including vesting requirements, are determined by the Company’s board of directors, subject to the provisions of the Plans. Options granted by the Company typically vest over four years and have a contractual life of ten years. Restricted stock unit grants typically vest over two to three years. At December 31, 2021, the Company had 25,005,365 common shares authorized for issuance under the 2018 Plan and 10,298,664 common shares available for future grant under the 2018 Plan. Equity-Based Compensation Expense The Company recognized stock-based compensation expense totaling $102.4 million, $66.0 million, and $49.5 million during the years ended December 31, 2021, 2020 and 2019, respectively. Stock‑based compensation expense by classification within the consolidated statements of operations and comprehensive income (loss) is as follows (in thousands):
|  | Years Ended December 31, |
|  | 2021 |  |  | 2020 |  |  | 2019 |
Research and development |  | $ | 59,683 |  |  | $ | 35,120 |  |  | $ | 23,273 |
General and administrative |  |  | 42,707 |  |  |  | 30,898 |  |  |  | 20,784 |
Loss from equity method investment |  |  | — |  |  |  | — |  |  |  | 5,467 |
Total |  | $ | 102,390 |  |  | $ | 66,018 |  |  | $ | 49,524 |
As of December 31, 2021, there was $150.6 million and $71.4 million of unrecognized compensation expense related to unvested stock options and restricted stock units, respectively, that is expected to be recognized over a weighted-average period of 2.7 and 2.5 years, respectively. Stock Options The fair value of each option issued to employees was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:
|  | Years Ended December 31, |
|  | 2021 |  |  | 2020 |  |  | 2019 |
Options granted |  |  | 1,616,255 |  |  |  | 2,182,773 |  |  |  | 2,832,784 |
Weighted-average exercise price |  | $ | 124.32 |  |  | $ | 68.91 |  |  | $ | 39.16 |
Weighted-average grant date fair value |  | $ | 77.38 |  |  | $ | 42.28 |  |  | $ | 24.57 |
Assumptions: |  |  |  |  |  |  |  |  |
Expected volatility |  |  | 70.3 | % |  |  | 69.2 | % |  |  | 68.9 | %
Expected term (in years) |  |  | 6.0 |  |  |  | 6.0 |  |  |  | 6.0 |
Risk-free interest rate |  |  | 1.0 | % |  |  | 0.6 | % |  |  | 2.2 | %
Expected dividend yield |  |  | 0.0 | % |  |  | 0.0 | % |  |  | 0.0 | %
The following table summarizes stock option activity under the Company’s equity award plans (intrinsic value in thousands):
|  | Shares |  |  | Weighted- Average Exercise Price |  |  | Weighted- Average Remaining Contractual Term (years) |  |  | Aggregate Intrinsic Value |
Outstanding at December 31, 2020 |  |  | 8,101,980 |  |  | $ | 42.44 |  |  |  | 7.8 |  |  | $ | 896,666 |
Granted |  |  | 1,616,255 |  |  | $ | 124.32 |  |  |  |  |  |  |
Exercised |  |  | (1,245,071 | ) |  | $ | 30.96 |  |  |  |  |  |  |
Cancelled or forfeited |  |  | (660,182 | ) |  | $ | 79.54 |  |  |  |  |  |  |
Outstanding at December 31, 2021 |  |  | 7,812,982 |  |  | $ | 58.07 |  |  |  | 7.4 |  |  |  | 219,103 |
Exercisable at December 31, 2021 |  |  | 4,598,353 |  |  | $ | 40.86 |  |  |  | 6.6 |  |  | $ | 174,056 |
Vested and expected to vest at December 31, 2021 |  |  | 7,812,982 |  |  | $ | 58.07 |  |  |  | 7.4 |  |  | $ | 219,103 |
During 2021 and 2020, the Company did no t grant stock option awards subject to performance-based or market-based vesting conditions. As of December 31, 2021, options to purchase 998,504 common shares subject to performance-based vesting conditions were vested, as performance conditions were achieved, and there were 123,057 options to purchase common shares subject to performance-based vesting conditions outstanding. Activity related to stock options subject to performance-based vesting conditions is included in the table above. During 2017, the Company granted 150,000 options with market-based vesting conditions, of which 75% vest at the end of a three-year service period and 25% vest at the end of a four-year service period. Upon achieving a specified average stock price in prior years, the market conditions were satisfied. Expense for the options is being recognized over the requisite service period. As of December 31, 2021, 150,000 of the stock options had vested. The total intrinsic value (the amount by which the fair market value exceeded the exercise price) of stock options exercised during the year ended December 31, 2021, 2020 and 2019 was $119.5 million, $104.2 million, and $42.2 million, respectively. Restricted Stock The following table summarizes the restricted stock activity under the Company’s equity award plans:
|  | Shares |  |  | Weighted- Average Grant Date Fair Value |
Unvested balance at December 31, 2020 |  |  | 894,092 |  |  | $ | 70.55 |
Granted |  |  | 628,175 |  |  |  | 111.73 |
Vested |  |  | (455,440 | ) |  |  | 58.00 |
Cancelled or forfeited |  |  | (132,652 | ) |  |  | 100.25 |
Unvested balance at December 31, 2021 |  |  | 934,175 |  |  | $ | 100.14 |
During the years ended December 31, 2021, 2020 and 2019, the total fair value of restricted stock vested was $45.3 million, $21.6 million, and $3.6 million, respectively. Award modifications Equity award modifications for certain equity awards held by departing employees and non-employees for the years ended December 31, 2021, 2020 and 2019 were not material to the Company's stock-based compensation expense. Employee Stock Purchase Plan On July 19, 2016, the Company’s board of directors adopted its 2016 Employee Stock Purchase Plan, or the ESPP Plan, which was subsequently approved by its shareholders and became effective on October 19, 2016. The ESPP Plan authorizes the initial issuance of up to a total of 0.4 million shares of the Company’s common stock to participating employees. The Company activated its ESPP Plan on January 1, 2020. The Company issued 21,590 and 13,410 shares under the ESPP during the years ended December 31, 2021 and 2020, respectively.

X
- Definition The entire disclosure for share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -URI http://asc.fasb.org/topic&trid=2228938 + Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration