Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2024

Summary of Shares Available for Issuance Under 2020 Plan

A summary of the shares available for issuance under the 2020 Plan and Inducement Plan (collectively, the “Incentive Plans”) is as follows:

	2020 Plan	Inducement Plan
Balance at December 31, 2023	294	—
Authorized	566	100
Granted/Awarded	(31)	(4)
Cancelled/Forfeited	140	—
Balance at March 31, 2024	969	96

Summary of Option Award Activity

Option award activity under the Incentive Plans is set forth below:

	Options Outstanding
	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)		Aggregate Intrinsic Value
Outstanding at December 31, 2023		1,974		$	5.31		8.0	$	429
Options granted		34		$	4.12
Options exercised		(2	)	$	2.65
Options cancelled/forfeited		(108	)	$	6.45
Outstanding at March 31, 2024		1,898		$	5.23		8.1	$	332
Vested and expected to vest at March 31, 2024		1,898		$	5.23		8.1	$	332
Vested and exercisable at March 31, 2024		1,088		$	5.94		7.7	$	107

Summary of Stock Options Outstanding and Vested

The following table summarizes information about stock options outstanding and vested as of March 31, 2024:

	Options Outstanding						Options Vested
Exercise Price	Options Outstanding		Weighted Average Remaining Contractual Term (in Years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$2.15 - $3.10		355		8.8	$	2.66		102	$	2.66
$3.23		422		9.2	$	3.23		193	$	3.23
$3.27 - $5.95		54		8.3	$	4.63		12	$	5.78
$6.04		413		7.7	$	6.04		225	$	6.04
$6.07 - $8.62		654		7.1	$	7.44		556	$	7.45
		1,898		8.1	$	5.23		1,088	$	5.94

Summary of Fair Value of Stock Options was Estimated Using Assumptions

The fair value of stock options was estimated using the following assumptions for the three months ended March 31, 2024 and 2023:

	Three Months Ended March 31,
	2024	2023
Risk-free interest rate	3.9 - 4.2%	3.5 - 4.2%
Expected term (years)	6	6
Expected volatility	58%	70%
Dividends	0.0%	0.0%

Summary of Total Stock-Based Compensation Expense Recognized

The following table sets forth the total stock-based compensation expense recognized under the Incentive Plans and the 2020 ESPP in the Company's condensed statements of operations:

	Three Months Ended March 31,
	2024		2023
Revenue – product	$	2	$	—
Cost of revenue – product		51		83
Cost of revenue – service		29		46
Selling, general and administrative expenses		484		1,426
Research and development expenses		86		171
Total	$	652	$	1,726

Summary of Unrecognized Stock-based Compensation Expense Expected to be Amortized

Total unrecognized stock-based compensation expense is expected to be amortized as follows:

Fiscal Year	Amount
Remainder of 2024	$	1,414
2025		1,000
2026		222
2027		26
2028		—
Total unrecognized stock-based compensation expense	$	2,662

Restricted Stock Units

Summary of Restricted Stock Units Activity

Restricted stock unit activity under the Incentive Plans is set forth below:

	Restricted Stock Units Outstanding
	Number of Units			Weighted Average Grant Date Fair Value Per Share
Non-vested at December 31, 2023		483		$	3.04
Restricted stock units granted		2		$	3.55
Restricted stock units vested		(84	)	$	3.26
Restricted stock units cancelled		(14	)	$	2.65
Non-vested at March 31, 2024		387		$	3.01