13. Stock-Based Compensation

Employee Equity Incentive Plan

On September 20, 2017, the Company established its 2017 Omnibus Equity Incentive Program (the “2017 Plan”) which provides for the granting of equity-based awards to certain employees, directors, independent contractors, consultants and agents. Under the 2017 Plan, the Company may grant non-qualified stock options, stock appreciation rights, restricted stock units and other stock-based awards for up to 22,182 shares of common stock.

On April 19, 2021, the Company established its 2021 Omnibus Equity Incentive Plan (“2021 Equity Plan”). The maximum number of shares of common stock available for issuance under the 2021 Equity Plan is equal to the sum of (i) 30,000 shares of common stock and (ii) an annual increase on the first day of each year beginning in 2022 and ending in and including 2031, equal to the lesser of (A) five percent (5%) of the outstanding shares of common stock on the last day of the immediately preceding fiscal year and (B) such lesser amount as determined by the Board’s compensation committee. The 2021 Equity Plan provides for the grant of stock options (including qualified incentive stock options and nonqualified stock options), stock appreciation rights, restricted stock, restricted stock units, performance stock units, dividend equivalents, and other stock or cash settled incentive awards. Any shares covered by an award, or portion of an award, granted under the 2021 Equity Plan that expires or is forfeited, canceled, cash-settled, or otherwise terminated for any reason will again be available for the grant of awards under the 2021 Equity Plan.

Stock Options

Options become exercisable subject to vesting schedules up to four years from the date of the grant and subject to certain timing restrictions upon an employee’s separation of service and no later than 10 years after the grant date.

A summary of stock option activity as of and for the year ended December 31, 2024 is as follows:

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Stock options include grants to executives that contain both market-based and performance-based vesting conditions. There were no stock options granted that contain both market-based and performance-based vesting conditions during the year ended December 31, 2024. During the year ended December 31, 2024, 97 stock options were exercised and 1,276 market-based and performance-based stock options remain outstanding as of December 31, 2024.

There were no stock options granted during the year ended December 31, 2024. The weighted average grant date fair value of options granted for the years ended December 31, 2023 and 2022 was $12.57 and $12.09, respectively. The total intrinsic value of options exercised during the years ended December 31, 2024, 2023 and 2022 was $10.8 million, $75.6 million and $34.3 million, respectively.

The fair market value of each option granted for the years presented has been estimated on the grant date using the Black-Scholes-Merton option-pricing model with the following assumptions:

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The Company’s board of directors (the “Board”) did not declare or pay dividends on any Company stock during the years ended December 31, 2024, 2023 and 2022.

RSUs

RSUs are subject to vesting schedules up to four years from the date of the grant and subject to certain restrictions upon employee separation.

A summary of RSUs activity as of and for the year ended December 31, 2024 is as follows:

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The total grant date fair value of RSUs that vested during the years ended December 31, 2024, 2023 and 2022 was $64.1 million, $37.6 million and $35.3 million, respectively.

The weighted average grant date fair value of RSUs granted during the years ended December 31, 2023 and 2022 was $28.19 and $24.75, respectively.

PSUs

PSUs are subject to vesting and performance periods of up to approximately three years from the date of the grant.

A summary of PSUs activity as of and for the year ended December 31, 2024 is as follows:

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⁽¹⁾ For awards for which the performance period is complete, the number of outstanding PSUs is based on the actual shares that will vest upon completion of the service period. For awards for which the performance period is not yet complete, the number of outstanding PSUs is based on the participants earning 100% of their target PSUs.

The weighted average grant date fair value of PSUs granted during the year ended December 31, 2023 was $41.31.

The fair market value of TSR PSUs granted for the years presented has been estimated on the grant date using the Monte Carlo Simulation model with the following assumptions:

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Stock-based Compensation Expense

Total stock-based compensation expense recorded in the Consolidated Statements of Operations and Comprehensive Income was as follows:

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As of December 31, 2024, unrecognized stock-based compensation expense was $161.9 million, which is expected to be recognized over a weighted-average period of 1.3 years.

ESPP

In March 2021, the Board approved the Company’s 2021 ESPP. The ESPP qualifies as an “employee stock purchase plan” under Section 423 of the U.S. Internal Revenue Code of 1986, as amended.

The Company reserved 3,000 shares of common stock for issuance under the ESPP. The share reserve increases on the first day of each calendar year beginning on January 1, 2022 and ending on and including January 1, 2031, equal to the lesser of (i) one percent (1%) of the aggregate number of shares of common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares of common stock as is determined by the Board.

Purchases are accomplished through participation in discrete offering periods. The ESPP is available to most of the Company’s employees. The current offering period began on December 1, 2024 and will end on May 31, 2025. The Company expects the program to continue consecutively for six-month offering periods for the foreseeable future.

Under the ESPP, eligible employees are able to acquire shares of the Company’s common stock by accumulating funds through payroll deductions. Company employees are generally eligible to participate in the ESPP if they have completed six months of continuous service with the Company as of the last day of the enrollment period. Eligible employees are able to select a rate of payroll deduction between 1% and 15% of their eligible compensation, up to a $25 annual contribution limit. The purchase price for shares of common stock purchased under the ESPP is 85% of the lesser of the fair market value of the common stock on (i) the first trading day of the applicable offering period and (ii) the last trading day of the applicable offering period. Employees are required to hold shares purchased for minimum of six months following the purchase date. An employee’s participation automatically ends upon termination of employment for any reason. A participant may cancel enrollment or lower their contributions once during an offering period, but no later than 30 days before the end of an offering period. Upon the termination of an employee’s participation in the ESPP, payroll deductions will be stopped and refunded.

Stock-based compensation expense for the ESPP is recognized on a straight-line basis over the requisite service period of each award. Stock-based compensation expense related to ESPP totaled $1.1 million, $0.8 million and $0.6 million for years ended December 31, 2024, 2023 and 2022, respectively.