10.   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 up to 22,182 shares of common stock.

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.

Restricted stock units are 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.

A summary of stock option activity for the three-months ended March 31, 2021 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 three months ended March 31, 2021. As of March 31, 2021, 3,433 market-based and performance-based awards were outstanding. As of March 31, 2021, the Company did not consider the performance condition to be probable and did not recognize any expense associated with these options.

The weighted average grant date fair value of options granted during the three months ended March 31, 2021 and 2020 was $8.39 and $3.18, respectively The total intrinsic value of options exercised during the three months ended March 31, 2021 and 2020 was $3.3 million and $0.2 million, respectively.

The fair market value of each option granted during the three months ended March 31, 2021 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 of the Company’s common or preferred stock during the three months ended March 31, 2021 or during the three months ended March 31, 2020.

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A summary of restricted stock unit activity for the three-months ended March 31, 2021 is as follows:

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As of March 31, 2021, unrecognized stock-based compensation expense was $24.2 million, which is expected to be recognized over a weighted-average period of 1.3 years.

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

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