Supplementary Balance Sheet Information

3 Months Ended

Mar. 31, 2022

Note 5 – Supplementary Balance Sheet Information

Property and equipment consist of the following (in thousands):


	March 31, 2022			December 31, 2021
Lab equipment	$	6,802		$	6,784
Leasehold improvements		2,355			2,339
Computer equipment		803			700
Furniture and fixtures		391			391
Software		600			600
Vehicles		97			97
Construction in process		142			17
		11,190			10,928
Less: accumulated depreciation		(7,162	)		(6,749	)
Total property and equipment, net	$	4,028		$	4,179

Depreciation expense for the three months ended March 31, 2022 and 2021 was $0.4 million and $0.3 million, respectively.

Intangible assets, excluding goodwill, consist of the following (in thousands):


	March 31, 2022							December 31, 2021
	Cost		Accumulated Amortization			Net Carrying Value		Cost		Accumulated Amortization			Net Carrying Value
Intangible assets subject to amortization
Patents	$	1,747	$	(588	)	$	1,159	$	1,755	$	(566	)	$	1,189
Purchased technology		16,900		(7,042	)		9,858		16,900		(6,572	)		10,328
Intangible assets not subject to amortization
Trademarks		114		—			114		100		—			100
Total	$	18,761	$	(7,630	)	$	11,131	$	18,755	$	(7,138	)	$	11,617

Amortization expense related to definite-lived intangible assets was $0.5 million for both the three months ended March 31, 2022 and 2021.

Future estimated amortization expense of intangible assets is (in thousands):

Accrued liabilities consist of the following (in thousands):


	March 31, 2022		December 31, 2021
Compensation related accruals	$	2,594	$	4,029
Accrued clinical trial expense		893		870
Other expenses		2,686		2,766
Total accrued liabilities	$	6,173	$	7,665