The Company’s Equity Incentive Plan (“Equity Plan”) provides long-term incentives to the Company’s key employees, including officers, directors, consultants and advisers (“Eligible Participants”), and is designed to align stockholder and employee interests. Under the Equity Plan, the Company may grant incentive stock options, nonstatutory stock options, restricted stock awards, restricted stock units, and other stock based awards or any combination thereof to Eligible Participants. The Compensation Committee of the Company’s Board of Directors establishes the terms and conditions of any awards granted under the plans. At the time of grant, the Company takes into consideration the timing of the stock based award and evaluates for conditions that could result in the award to be considered spring loaded. As of December 31, 2023 and 2022, the number of shares of common stock that was authorized and remained available for issuance under the Equity Plan was 20.6 million and 9.8 million, respectively.

The Company has granted incentive stock options under the Equity Plan. These options have various vesting terms, but generally vest in equal installments over three years and expire in ten years. The Company recognizes compensation expense for stock option grants over the Eligible Participants' requisite service period, which is generally based on the vesting period and the fair value at the date of grant using the Black-Scholes option pricing model. The table below summarizes the assumptions for the indicated periods:


	Year Ended December 31,
	2023			2022			2021
Risk-free interest rate	3.9		%	1.4		%	0.4		%
Expected term of options (years)	5			5			5
Volatility	65		%	100		%	62		%
Weighted average grant-date fair value per share	$	0.73		$	0.86		$	0.17


	Shares	Weighted Average Exercise Price
Outstanding at January 1, 2023	8,099,885	$	1.29
Granted	800,000	1.27
Exercised	(61,484)	0.70
Forfeited or expired	(554,400)	1.99
Outstanding at December 31, 2023	8,284,001	1.24

Exercisable at December 31, 2023	6,736,494	$	1.26

The intrinsic value of a stock option is the amount by which the market value of the underlying stock exceeds the exercise price of the option. For the years ended December 31, 2023, 2022 and 2021, the total intrinsic value of all stock options exercised was less than $0.1 million, $0.4 million and $0.7 million, respectively. The aggregate intrinsic value of all outstanding stock options at December 31, 2023 was $6.9 million with a remaining contractual life of 5.3 years. The aggregate intrinsic value of all vested stock options that were exercisable at December 31, 2023 was $5.7 million based on a per grant calculation with a remaining contractual life of 4.7 years. Net cash proceeds during the year ended December 31, 2023 from the exercise of stock options was less than $0.1 million.

For each of the years ended December 31, 2023, 2022 and 2021, the Company recognized $0.5 million of compensation expense related to stock options. As of December 31, 2023, unrecognized compensation expense related to non-vested stock options outstanding was approximately $0.6 million to be recognized over a weighted-average period of 1.6 years.

Grants of restricted stock have varying vesting criteria, including immediate, one year from the grant date, in equal annual installments over three years or based on performance criteria. Non-vested shares are generally forfeited upon the termination of employment. Holders of restricted stock awards are entitled to all rights of a stockholder of the Company with respect to the restricted stock, including the right to vote the shares and receive any dividends or other distributions. Compensation expense associated with restricted stock is measured based on the grant date fair value of the common stock and is recognized on a straight line basis over the vesting period. The table below summarizes the weighted average grant date fair value of restricted stock for the indicated periods:


	Shares	Weighted Average Grant Date Fair Value
Nonvested at January 1, 2023	9,953,866	$	1.47
Granted	7,860,740	1.36
Vested	(8,819,458)	1.29
Forfeited	(159,067)	1.47
Nonvested at December 31, 2023	8,836,081	$	1.56

Included in the vested balance during the year ended December 31, 2023 were approximately 3.4 million performance-based restricted stock awards that vested upon the achievement of certain milestones during the year.

For the years ended December 31, 2023, 2022 and 2021, the Company recognized $13.1 million, $10.4 million and $5.6 million, respectively, of compensation expense related to restricted stock awards. The increase in compensation expense during 2023 was driven primarily by performance grants to certain employees associated with their efforts under the Service Agreements as well as other performance criteria. The total fair value, as calculated on the day of vesting, of restricted stock awards that vested during 2023, 2022 and 2021 was $11.6 million, $14.6 million, and $8.6 million, respectively. As of December 31, 2023, unrecognized compensation expense related to unvested restricted stock outstanding was approximately $10.2 million to be recognized over a weighted-average period of 1.7 years.

During 2023, the Company granted 44.5 million restricted stock units ("RSUs") to certain executives which are earned over a four-year performance period. The RSUs vest upon the Company's common stock trading at various price levels throughout the performance period. The RSUs were valued using a Monte Carlo simulation model. As of the grant date, September 25, 2023, the fair value of the RSUs was $39.5 million. This total fair value will be recognized over the derived service period, estimated to be 2.6 years. The Monte Carlo simulation was computed using the following assumptions:

For the year ended December 31, 2023, the Company recognized $6.7 million of compensation cost related to these awards. As of December 31, 2023, unrecognized compensation expense related to unvested market-based RSUs was approximately $32.8 million to be recognized over a weighted-average period of 1.5 years. No market-based RSUs vested, expired or were forfeited during 2023.

The Company has an annual bonus plan designed to reward designated key employees' efforts to exceed the Company's financial performance goals for the designated calendar year ("Plan Year"). The bonus pool available for distribution is determined based on the Company's adjusted EBITDA performance during the Plan Year. The bonus may be paid in cash or the Company's common stock, subject to certain approvals.

For the 2023 Plan Year, the Company's adjusted EBITDA performance was within the bonus payout threshold according to the plan document. As of December 31, 2023, $2.5 million was accrued on the Company's consolidated balance sheet related to this bonus payment, which is expected to be made in the form of common stock during the first quarter of 2024.

The Company has an Employee Stock Purchase Plan (the “Plan”) which provides eligible employees of the Company with an opportunity to acquire shares of its common stock at a discount. As of December 31, 2023, the maximum aggregate number of shares of common stock that may be purchased through the Plan was 20.0 million shares (subject to adjustment as allowed in the Plan) and the Company has issued approximately 13.6 million shares.

For 2023 and 2022, the Company received $0.9 million and $0.7 million, respectively, in proceeds related to shares issued under the Plan. For each of the years ended December 31, 2023, 2022 and 2021, the Company recorded compensation expense of approximately $0.4 million, which is reflected in marketing, general and administrative expenses. The fair value of the employees’ stock purchase rights granted under the ESPP is estimated using the Black-Scholes option pricing model.