8. SHARE-BASED COMPENSATION

3 Months Ended

Mar. 31, 2023

Disclosure Of Compensation Related Costs Sharebased Payments Abstract

Schedule of Valuation Allowance for Impairment

. SHARE-BASED COMPENSATION

We issue share-based compensation to employees in the form of stock options, restricted stock

nits (RSUs), and performance stock units (PSUs). We account for the share-based awards by recognizing the fair value of share-based compensation expense on a straight-line basis over the service period of the award, net of estimated forfeitures. The fair value of stock options is estimated on the grant date using the Black-Scholes option pricing model. The fair value of RSUs and

non-executive

PSUs is determined by the closing price of our common stock on the grant date. Changes in estimated inputs or using other option valuation methods may result in materially different option values and share-based compensation expense.

The following table summarizes the amount of share-based compensation expense by line item on the statements of operations:


Share-based compensation expense	Three Months Ended
	March 31,
(in thousands)	2023		2022
Research and development expense	$	757	$	1,833
Sales, marketing, general and administrative expense		2,192		1,901

	$	2,949	$	3,734

Options activity and positions

The following table summarizes shares, weighted-average exercise price, weighted-average remaining contractual term and aggregate intrinsic value of options outstanding and options exercisable as of March 31, 2023:


Options	Shares		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding as of March 31, 2023		943,000	$	1.26		4.5	$	1,425
Exercisable as of March 31, 2023		943,000	$	1.26		4.5	$	1,425

As of March 31, 2023, there is no unrecognized share-based employee compensation related to stock options.

Restricted stock activity and positions

The following table summarizes activity and positions with respect to RSUs and PSUs for the three months ended March 31, 2023:


				Weighted-average
	Shares			price
Unvested as of December 31, 2022		8,866,000		$	3.85
Granted		161,000			2.35
Vested		(458,000	)		9.12
Forfeited		(191,000	)		12.71

Unvested as of March 31, 2023		8,378,000		$	3.40

During the quarter ended March 31, 2023, we issued 106,000 shares for the partial achievement of internal performance milestones during the fourth quarter of 2022. These shares were valued based on the closing price of our common stock on the dates of grant and vest quarterly over two years. We had canceled 426,000 PSUs in the fourth quarter of 2022 related to the same internal performance milestones.

As of March 31, 2023, our unrecognized share-based compensation related to RSUs was $9.4 million, which we plan to expense over the next 1.5 years, our unrecognized share-based compensation related to executive PSUs was $7.2 million, which we plan to expense over the next 2.5 years, and our unrecognized share-based compensation related to the

non-executive

PSUs was $1.4 million, which we plan to expense over the next 1.1

years.