11.   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.

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, 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.

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 as of and for the six-months ended June 30, 2021 and December 31, 2020 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 six months ended June 30, 2021. As of June 30, 2021, 3,433 market-based and performance-based awards were outstanding. As of June 30, 2021, the Company did not consider the performance condition to be probable and did not recognize any expense associated with these options.

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The weighted average grant date fair value of options granted during the six months ended June 30, 2021 and 2020 was $9.23 and $2.65, respectively. The total intrinsic value of options exercised during the six months ended June 30, 2021 and 2020 was $30.4 million and $0.3 million, respectively.

The fair market value of each option granted during the six months ended June 30, 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 six months ended June 30, 2021 or during the six months ended June 30, 2020.

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A summary of restricted stock unit activity as of and for the six months ended June 30, 2021 and December 31, 2020 is as follows:

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The total grant date fair value of restricted stock units that vested during the six months ended June 30, 2021 was $2.2 million.

As of June 30, 2021, unrecognized stock-based compensation expense was $24.6 million, which is expected to be recognized over a weighted-average period of 1.4 years.

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

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