Stock-Based Compensation Plans

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement, Noncash Expense [Abstract]

The components of stock-based compensation expense were as follows:


	Three months ended March 31,
	2023		2022
	(in thousands)
2021 Stock Incentive Plan	$	2,890	$	4,607
Employee Stock Purchase Plan	47		22
Total Stock Compensation Expense	$	2,937	$	4,629

The 2021 Stock Incentive Plan (the “2021 Plan”) authorized 1,800,000 shares for issuance, plus the number of shares remaining for issuance under the prior stock plan and any future forfeited awards under the prior plan. Stock-based compensation is in the form of restricted stock awards (“RSAs”). The RSAs are subject to either service-based vesting, which is typically between one and four years, in which a specific period of continued employment must pass before an award vests, or performance-based vesting, which is typically between one and two years. The expense associated with these awards is recognized on a straight-line basis over the respective vesting period, with forfeitures accounted for as they occur. For any vesting tranche of an award, the cumulative amount of compensation cost recognized is equal to the portion of the grant‑date fair value of the award tranche that is actually vested at that date.

As of March 31, 2023, the Company had granted 1,256,700 RSAs under the 2021 Plan and had 637,896 shares available for future issuance. The fair value of the restricted stock awards equaled the stock price at the grant date.

The following table summarizes the restricted stock activity during the three months ended March 31, 2023:


			Shares
Balance of unvested shares as of December 31, 2022			495,948
Shares granted			—
Shares forfeited			(1,999)
Shares vested			—
Balance of unvested shares as of March 31, 2023			493,949

Under the Employee Stock Purchase Plan (“ESPP”), as amended and restated effective November 2021, 425,000 shares of common stock have been reserved for issuance. Eligible employees may designate no more than 10% of their base cash compensation to be deducted each pay period for the purchase of common stock under the ESPP. Participants may purchase no more than 1,000 shares or $25,000 of common stock in any one calendar year. Each January 31 and July 31, shares of common stock are purchased with the employees’ payroll deductions from the immediately preceding six months at a price per share of 85% of the lesser of the market price of the common stock on the purchase date or the market price of the common stock on the date of entry into an offering period. During the three months ended March 31, 2023 and 2022, 5,506 and 9,919 shares of common stock, respectively, were issued under the ESPP. The Company issues new shares through its transfer agent upon an employee stock purchase.