Note 12 - Income Taxes

12 Months Ended

Dec. 31, 2022

Notes to Financial Statements

Income Tax Disclosure [Text Block]

(12) Income Taxes

The Company’s provision for income taxes for the years ended December 31, 2022 and 2021 was $0 for both years.

The provision for income taxes differs from the amount which would result by applying the federal statutory income tax rate to pre-tax loss for the years ended December 31, 2022 and 2021. The reconciliation of the provision computed at the federal statutory rate to the Company’s provision (benefit) for income taxes was as follows (in thousands):

	Years ended December 31,
	2022			2021
Tax at federal statutory rate	$	(2,500	)	$	(2,651	)
State, net of federal benefit		(190	)		—
Research and development credit		(291	)		(279	)
Share-based compensation		101			264
Other		—			2
Change in valuation allowance		2,880			2,664
Total provision for income taxes	$	—		$	—

Deferred income taxes reflect the net tax effects of temporary differences between carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes as well as net operating loss and tax credit carryforwards, net of any adjustment for unrecognized tax benefits. The components of the net deferred income tax assets as of December 31, 2022 and 2021 were as follows (in thousands):

	Years ended December 31,
	2022			2021
Accrued compensation	$	189		$	191
Inventory adjustments		24			15
Depreciation and amortization		17			24
Share-based compensation		569			595
Net operating loss and tax credit carryforwards		31,499			30,277
Research and development capitalization		1,674			—
Other		12			2
Gross Deferred Tax Asset		33,984			31,104
Valuation Allowance		(33,984	)		(31,104	)
Net deferred tax asset	$	—		$	—

The Company had approximately $109.5 million and $63.2 million of federal and state net operating loss (NOL) carryforwards, respectively, as of December 31, 2022. For tax reporting purposes, operating loss carryforwards are available to offset future taxable income; such carryforwards expire in varying amounts beginning in 2022 and 2028 for federal and state purposes, respectively, with 2018-2022 federal NOLs having no expiration date. Under current federal and California law, the amounts of and benefits from net operating losses carried forward may be impaired or limited in certain circumstances. Events which may cause limitations in the amount of net operating losses that the company may utilize in any one year include, but are not limited to, a cumulative ownership change of more than 50% over a three-year period.

Generally, utilization of the net operating loss carryforwards and credits may be subject to a substantial annual limitation due to the ownership change limitations provided by Section 382 of the Code, which discusses limitations on NOL carryforwards and certain built-in losses following ownership changes, and Section 383 of the Code, which discusses, special limitations on certain excess credits, etc., and similar state provisions. Accordingly, the Company’s ability to utilize net operating loss carryforwards and tax credit carryforwards may be limited, potentially significantly, as the result of such an “ownership change.” The Company has not yet performed a comprehensive study to determine if it has undergone any ownership changes. If the Company is able to potentially utilize its net operating loss carryforwards and tax credit carryforwards, it will perform a comprehensive Section 382 and 383 study to determine what, if any, limitation on its ability to utilize its NOLs exists.

As of December 31, 2022, the Company had federal and state research and development credits of approximately $3.5 million and $2.6 million available to offset future federal and state income taxes, respectively. The federal tax credit carryforward expires beginning in 2028. The state credit carryforwards have no expiration.

The Company does not believe that these assets are realizable on a more likely than not basis; therefore, the net deferred tax assets have been fully offset by a valuation allowance. The Company did not have deferred tax liabilities as of December 31, 2022 or 2021. The net increase in the total valuation allowance for the year ended December 31, 2022 was $2.9 million, primarily from the net operating losses generated. The net increase in the total valuation allowance for the year ended December 31, 2021 was $2.7 million, primarily from the net operating losses generated. No liability related to uncertain tax positions is reported in the financial statements.

The aggregate changes in the balance of gross unrecognized tax benefits were as follows (in thousands):

	Years ended December 31,
	2022		2021
Balance, beginning of year	$	1,368	$	1,235
Additions based on tax positions related to the current year		151		158
Reductions for tax positions related to prior years		—		(25	)
Balance, end of year	$	1,519	$	1,368

Recognition of approximately $1,106,000 and $991,000 of unrecognized tax benefits would impact the effective rate at December 31, 2022 and 2021 respectively, if recognized. Increases in 2022 relate to increased research and development activity.