The Company maintains three equity incentive plans: the 2018 Equity Incentive Plan (“2018 Plan”), the 2019 Employee, Director and Consultant Equity Incentive Plan (“2019 Plan”) and the 2020 Employee, Director, and Consultant Equity Incentive Plan (“2020 Plan” and collectively, “Incentive Plans”). The 2020 Plan serves as the successor to the 2019 Plan and 2018 Plan and provides for the issuance of incentive stock options ("ISOs"), stock grants and stock-based awards to employees, directors, and consultants of the Company. No further awards will be issued under the 2018 Plan and 2019 Plan. As of March 31, 2024, a total of 4,065,385 shares were available for grant under the 2020 Plan.

The Incentive Plans are administered by the Company's Board of Directors. Notwithstanding the foregoing, the Board of Directors may delegate concurrent responsibility for administering each plan, including with respect to designated classes of persons eligible to receive an award under each plan, to a committee or committees (which term shall include subcommittees) consisting of one or more members of the Board of Directors (collectively, the “Plan Administrator”), subject to such limitations as the Board of Directors deems appropriate.

In November 2020, the Board of Directors and stockholders approved the 2020 Plan and reserved an aggregate of 2,284,053 shares of common stock for issuance under the 2020 Plan. Pursuant to the 2020 Plan, the number of shares available for issuance under the 2020 Plan may be increased on January 1 of each year, beginning on January 1, 2021, and ending on January 2, 2030, in an amount equal to the lesser of (i) 4% of the outstanding shares of the Company’s common stock on such date or (ii) such number of shares determined by the Plan Administrator.

The 2020 Plan provides for the grant of ISOs, nonqualified stock options, stock grants, and stock-based awards that are based in whole or in part by reference to the Company’s common stock.

•The Plan Administrator may grant options designated as incentive stock options or nonqualified stock options. Options shall be granted with an exercise price per share not less than 100% of the fair market value of the common stock on the grant date, subject to certain limitations and exceptions as described in the plan agreements. Generally, the maximum term of an option shall be 10 years from the grant date. The Plan Administrator shall establish and set forth in each instrument that evidences an option the time at which, or the installments in which, the option shall vest and become exercisable.

•The Plan Administrator may grant stock grants and stock-based awards, including securities convertible into shares, stock appreciation rights, phantom stock awards or stock units on such terms and conditions which may be based on continuous service with the Company or related company or the achievement of any performance goals, as the Plan Administrator shall determine in its sole discretion, which terms, conditions and restrictions shall be set forth in the instrument evidencing the award.

RSUs granted to certain executives, employees and members of the Board of Directors expire 10 years after the grant date. The awards generally have a time-based vesting requirement (based on continuous employment). Upon vesting, the RSUs convert into shares of the Company's common stock. The stock-based compensation expense related to service-based awards is recorded over the requisite service period. During the first quarter of 2023, the Company granted RSU awards that are expected to vest with two equal vesting tranches, one of which vested on October 31, 2023, and the second of which is scheduled to vest on October 31, 2024. During the second quarter of 2023, the Company granted RSU awards to members of the Board of Directors that are expected to vest on the one year anniversary of the grant date.

The following table summarizes the activity related to the Company's RSUs for the three months ended March 31, 2024. For purposes of this table, vested RSUs represent the shares for which the service condition had been fulfilled during the three months ended March 31, 2024:


	Number of RSUs	Weighted average grant date fair value
Balance, December 31, 2023	1,242,210	$	3.06
Vested	(112,720)	$	13.75
Balance, March 31, 2024	1,129,490	$	1.99

As of March 31, 2024, total unamortized stock-based compensation cost related to unvested RSUs was $1,269 and the weighted-average period over which the compensation is expected to be recognized is less than one year. For the three months ended March 31, 2024, the Company recognized $752 of total stock-based compensation expense for RSUs. As of March 31, 2024, there were 6,357 RSUs which had previously vested, but were not yet issued due to the recipients' elections to defer the awards.


	Number of PSUs	Weighted average grant date fair value
Balance, December 31, 2023	921,182	$	1.77
Vested	(180,298)	$	1.77
Forfeited	(740,884)	$	1.77
Balance, March 31, 2024	—	$	—

During the three months ended March 31, 2024, the PSU forfeitures were due to employee terminations and performance conditions that were not satisfied, while PSU vests were from awards granted in prior periods. The majority of the PSUs outstanding as of December 31, 2023 were forfeited in the three months ended March 31, 2024, as a result of not meeting certain performance conditions. As of March 31, 2024, there was no unamortized stock-based compensation cost or unvested PSUs outstanding. For the three months ended March 31, 2024, the Company recognized $72 of total stock-based compensation expense for PSUs. The Company issued 1,372,188 additional PSUs in April 2024, which are scheduled to vest in April 2025, assuming certain performance metrics are achieved.

The vesting of stock options is subject to certain change in control provisions as provided in the incentive plan agreements and options may be exercised up to 10 years from the date of issuance.

There were no stock options granted or exercised during the three months ended March 31, 2024. The following table summarizes the stock option activity for the three months ended March 31, 2024:


	Number	Weighted average exercise price		Weighted average grant date fair value		Weighted average remaining contractual term (years)
Outstanding as of December 31, 2023	571,359	$	9.47	$	2.01	3.69
Cancelled	(127,576)	$	8.44	$	0.92
Forfeited	(39)	$	11.06	$	9.89
Outstanding as of March 31, 2024	443,744	$	9.76	$	2.33	4.44
Options exercisable as of March 31, 2024	427,922	$	9.38	$	1.95	4.35
Vested and expected to vest as of March 31, 2024	443,744	$	9.76	$	2.33	4.44


	Number	Weighted average grant date fair value
Unvested as of December 31, 2023	16,674	$	12.15
Vested	(813)	$	3.85
Forfeited	(39)	$	9.89
Unvested as of March 31, 2024	15,822	$	12.59