8.

Income taxes

As of December 31, 2025 and 2024, a valuation allowance was recorded against all deferred tax assets due to our cumulative net loss position.

The components of our loss from continuing operations before income taxes are as follows for the periods indicated:

  ​ ​ ​

Year Ended

December 31, 

(in thousands)

2025

  ​ ​ ​

2024

Domestic

$

(53,324)

$

(59,922)

Foreign

 

 

12

Loss from continuing operations before taxes

$

(53,324)

$

(59,910)

The components of our provision for income taxes are as follows for the periods indicated:

  ​ ​ ​

Year Ended

December 31, 

(in thousands)

2025

  ​ ​ ​

2024

Current

Federal and state

$

$

Foreign

 

(18)

 

55

Total provision for income taxes

$

(18)

$

55

The reconciliation of taxes at the federal statutory rate to our provision for income taxes are as follows for the periods indicated:

  ​ ​ ​

Year Ended

Year Ended

December 31, 

December 31, 

2025

2024

2025

  ​ ​ ​

2024

 

U.S. federal statutory tax rate

$

(11,198)

$

(12,581)

21.0

%

21.0

%

State and local income taxes, net of federal income tax effect(1)

(28)

(26)

0.1

Foreign tax effects

3

5

Effect of cross-border tax laws

1

Tax credits

(313)

(550)

0.5

0.9

Changes in valuation allowances

10,152

11,930

(19.0)

(19.9)

Nontaxable or nondeductible items

Share-based payment awards

1,008

874

(1.9)

(1.5)

Meals and entertainment

332

269

(0.7)

(0.4)

Changes in unrecognized tax benefits

26

133

(0.2)

Total

$

(18)

$

55

0.0

%

(0.1)

%

As of December 31, 2025 and 2024, the U.S. federal corporate income tax rate of 21% was used as the applicable statutory rate. Minnesota makes up the majority (greater than 50 percent) of the state income tax expense, net of federal income tax effect.

Significant components of net deferred tax assets were as follows for the periods indicated:

  ​ ​ ​

Year Ended

December 31, 

(in thousands)

2025

  ​ ​ ​

2024

Deferred tax assets

Net operating loss carryforwards

$

111,304

$

98,329

R&D tax credits

10,414

10,147

Capitalized R&D expenses

2,748

8,015

Non-qualified stock options

5,585

4,482

Start-up costs

225

452

Accrued vacation

140

227

Other

1,507

450

Total deferred tax assets

131,923

122,102

Valuation allowance

(131,923)

(122,102)

Net deferred tax assets

$

$

As of December 31, 2025, we had federal and state net operating loss carryforwards (“NOLs”) of approximately $483.7 million and $9.7 million, respectively. The federal NOLs began expiring in 2021 and the state NOLs began expiring in 2020. As of December 31, 2025, we had federal and state tax credit carryforwards of approximately $10.3 million and $1.9 million, respectively. The federal tax credit carryforwards began expiring in 2021 and the state tax credits will begin expiring in 2028.

Utilization of NOLs may be subject to an annual limitation due to the ownership change limitations provided by Section 382 of the Internal Revenue Code of 1986, as amended, and similar state provisions. We have not performed a detailed analysis to determine whether an ownership change has occurred. Such a change of ownership would limit our utilization of the NOLs and could be triggered by subsequent sales of securities by us or our stockholders.

The changes to our gross unrecognized tax benefits were as follows for the periods indicated:

  ​ ​ ​

Year Ended

December 31, 

(in thousands)

2025

  ​ ​ ​

2024

Gross unrecognized tax benefits at beginning of year

$

2,346

$

2,221

Gross increases:

Prior year tax positions

Current year tax positions

135

182

Gross decreases:

Prior year tax positions

(80)

(57)

Gross unrecognized tax benefits at end of year

$

2,401

$

2,346

All of these unrecognized tax benefits, if recognized, would impact the effective tax rate before taking consideration of the valuation allowance. The amount of unrecognized tax benefits subjected to the valuation allowance was $1.8 million for the each of the years ended December 31, 2025 and 2024. We recognized a nominal amount and approximately $0.1 million of interest or penalties for each of the years ended December 31, 2025 and 2024. Total accrued interest and penalties were $0.6 million and $0.5 million for the years ended December 31, 2025 and 2024, respectively. We recognize accrued interest and penalties related to unrecognized tax positions as a component of income tax expense. We do not expect a significant change in the amount of unrecognized tax benefits in the next year.

We are subject to U.S. federal income tax as well as income tax of multiple state and foreign jurisdictions. Tax years from 2006 through present remain open for audit under the applicable statute of limitations due to the carryover of the unused NOLs and tax credit carryforwards. We do not have any tax audits or other proceedings pending.

On July 4, 2025, the One Big Beautiful Bill Act (“OBBBA”) was enacted in the U.S. The OBBBA includes significant tax-related provisions, such as the permanent extension of certain expiring provisions of the Tax Cuts and Jobs Act, modifications to the international tax framework, and the restoration of favorable tax treatment for certain business provisions, including the deduction of certain R&D costs. The legislation has multiple effective dates, with certain provisions effective in 2025 and others implemented through 2027. The impacts of the OBBBA were taken into account in our provision for income taxes for fiscal year 2025. Because a valuation allowance has been recorded against all deferred tax assets, the impacts of the OBBBA were not material to our consolidated financial statements or related disclosures.

Historical Timeline

Fiscal YearFiled
2025Feb 13, 2026Showing above
2024Feb 18, 2025
2023Feb 9, 2024
2022Feb 10, 2023
2021Feb 22, 2022

About Income Taxes Disclosures

The income tax disclosure reveals how much a company actually pays in taxes versus what the statutory rate would predict. Analysts focus on the effective tax rate (ETR) reconciliation, which breaks down every item driving the gap between the 21% federal rate and the company's reported ETR — including R&D credits, foreign rate differentials, and state taxes. Deferred tax assets (DTAs) and their valuation allowances signal management's confidence in future profitability: a rising allowance suggests the company doubts it can use accumulated tax benefits. Uncertain tax benefit (UTB) reserves quantify exposure to IRS challenges on aggressive positions.

Key signals to watch: sudden ETR drops without clear operational reasons, large increases in valuation allowances, growing UTB balances, and significant unremitted foreign earnings. Post-TCJA, pay attention to GILTI and BEAT provisions that affect multinational tax structures. Compare the cash taxes paid (from the cash flow statement) against the income tax provision to gauge earnings quality.