Note 9 - Intangible Assets, Net

9 Months Ended

Sep. 30, 2022

Intangible Assets Disclosure [Text Block]

Note 9. Intangible Assets, net

Intangible assets consisted of the following for the periods indicated (in thousands):

	*September 30, 2022*
	*Gross*		*Accumulated*			*Intangible*
	*Amount*		*amortization*			*assets, net*
Patents	$	8,865	$	(5,155	)	$	3,710
Trademarks		50		(20	)		30
Total intangible assets	$	8,915	$	(5,175	)	$	3,740

	*December 31, 2021*
	*Gross*		*Accumulated*			*Intangible*
	*Amount*		*amortization*			*assets, net*
Patents	$	8,597	$	(4,779	)	$	3,818
Trademarks		35		(17	)		18
Total intangible assets	$	8,632	$	(4,796	)	$	3,836

For the three months ended September 30, 2022 and 2021, amortization expense for intangible assets, included in general and administrative expenses on the statement of operations, was $0.2 million and $0.1 million, respectively. For the nine months ended September 30, 2022 and 2021, included in general and administrative expenses on the statement of operations, the amortization expense for intangible assets, was each $0.5 million. The remaining weighted average amortization period for intangible assets is approximately 6 years.

At September 30, 2022, future amortization expense for intangible assets for future one year periods is estimated to be (in thousands):

2023			616
2024			616
2025			616
2026			616
2027			616
2028			616
thereafter			44
			3,740