Note 14. Stock-Based Compensation

The 2019 Equity Incentive Plan authorizes the granting of stock-based compensation awards to directors, employees, and consultants in the form of restricted stock awards or stock options that settle in shares of the Company’s common stock upon vesting.

The following table presents stock-based compensation expense by category:

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Stock-based compensation expense is recognized in Selling, general and administrative on the Condensed Consolidated Statements of Operations.

Restricted Common Stock Awards

Performance-based awards

Performance-based awards vest over a three-year performance period upon the successful completion of specified milestones related to added infrastructure capacity and Adjusted EBITDA through December 31, 2023.

The following table presents a summary of the Company’s performance-based awards activity:

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As of March 31, 2023, there was approximately $3.6 million of unrecognized compensation cost related to the performance-based awards, which is expected to be recognized over a remaining weighted-average vesting period of approximately eight months.

Service-based awards

Service-based awards generally vest over a one-to-two-year service period.

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The following table presents a summary of the Company’s service-based awards activity:

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As of March 31, 2023, there was approximately $38.5 million of unrecognized compensation cost related to the service-based awards, which is expected to be recognized over a remaining weighted-average vesting period of approximately 14 months.