Stock-based compensation expense is recorded in the consolidated statements of operations as follows (in thousands):


	Three months ended March 31,
	2026		2025
Cost of goods sold	$	25	$	73
Research and development		146		270
Sales and marketing		132		73
General and administrative		404		491
Total stock-based compensation expense	$	707	$	907

The following table summarizes the outstanding stock option activity during the period indicated (shares in thousands):


				Weighted average
	Number of stock options			Exercise price		Remaining contractual term (in years)		Aggregate intrinsic value (in thousands)
Balance at December 31, 2025		2,418		$	9.07		5.5	$	169
Granted		350		$	4.19
Exercised		(20	)	$	4.60
Expired/Forfeited		(33	)	$	4.89
Balance at March 31, 2026		2,715		$	8.53		5.7	$	1,193

Vested and exercisable at March 31, 2026		2,026		$	9.88		4.6	$	472
Vested and expected to vest at March 31, 2026		2,715		$	8.53		5.7	$	1,193

The weighted average grant-date fair value of options granted during the three months ended March 31, 2026 was $2.32. The grant-date fair value of each option award is estimated on the date of grant, using the Black-Scholes-Merton option-pricing model.

As of March 31, 2026, there was $1.6 million of unrecognized stock-based compensation costs related to unvested stock options granted under the Company’s equity plans. These costs are expected to be recognized over the next 2.4 years.

The following table summarizes the Company’s restricted stock unit (RSU) activity during the period indicated (shares in thousands):


	Restricted stock units			Weighted average grant date fair value
Balance at December 31, 2025		886		$	5.13
Grants		196		$	4.24
Vested and released		(323	)	$	4.89
Forfeited		(52	)	$	5.09
Balance at March 31, 2026		707		$	5.50

As of March 31, 2026, there was $2.4 million of unrecognized stock-based compensation costs related to non-vested RSUs, which are expected to be recognized over a remaining weighted-average vesting period of 2.3 years.

Share-settled compensation to non-employees was incurred and recognized as stock-based compensation expense and recorded in accrued expense. Within ninety days after the calendar year-end, the liabilities are settled in RSU grants and vest on the grant date. The share-settled obligations were $33.0 thousand and $0.1 million as of March 31, 2026 and December 31, 2025, respectively.

During the three months ended March 31, 2026, the Company received $0.1 million from the issuance of 19,785 shares under the ESPP.