10. Income Taxes

The Company incurred no current or deferred federal or state tax expense during the periods presented. The only tax expense is related to state minimum taxes.

The following is a reconciliation of the Company’s expected federal income tax provision (benefit) to the actual income tax provision (in thousands) (after the adoption of ASU 2023-09):

 

 

 

Year Ended December 31,

 

 

 

2025

 

Income tax (benefit) at statutory rate

 

$

(28,626

)

 

 

21.0

%

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

 

 

(10,362

)

 

 

7.6

%

Effects of changes in tax laws or rates enacted in the current period

 

 

 

 

 

 

Tax Credits

 

 

 

 

 

 

R&D tax credits

 

 

(2,952

)

 

 

2.2

%

Changes in valuation allowance

 

 

25,362

 

 

 

-18.6

%

Nontaxable or nondeductible items

 

 

 

 

 

 

Stock Compensation

 

 

5,886

 

 

 

-4.3

%

Nondeductible executive compensation

 

 

21

 

 

 

0.0

%

Other

 

 

202

 

 

 

-0.2

%

Changes in unrecognized tax benefits

 

 

10,363

 

 

 

-7.6

%

Other

 

 

108

 

 

 

-0.1

%

Income tax expense

 

$

2

 

 

 

0.0

%

(1) The state of California comprises greater than 50% of the Company’s state tax benefit.

The following is a reconciliation of the Company’s expected federal income tax provision (benefit) to the actual income tax provision (in thousands) (prior to the adoption of ASU 2023-09):

 

 

 

Year Ended December 31,

 

 

 

2024

 

Tax computed at federal statutory rate

 

$

(39,115

)

State tax, net of federal tax benefit

 

 

(8,429

)

Non-deductible compensation

 

 

35

 

Permanent differences

 

 

22

 

Stock Compensation

 

 

8,560

 

R&D tax credits

 

 

(7,672

)

Reserve for uncertain tax positions

 

 

8,612

 

Other

 

 

(135

)

Valuation Allowance

 

 

38,122

 

Income tax expense

 

$

 

 

Significant components of the Company’s deferred tax assets are summarized as follows (in thousands):

 

 

 

December 31,

 

 

 

2025

 

 

2024

 

Deferred tax assets:

 

 

 

 

 

 

Capitalized R&D expense

 

$

111,424

 

 

$

127,559

 

Net operating losses

 

 

186,855

 

 

 

147,019

 

R&D tax credits

 

 

66,653

 

 

 

63,126

 

Intangible asset amortization

 

 

8,000

 

 

 

8,692

 

Deferred revenue

 

 

2,298

 

 

 

1,147

 

Stock compensation

 

 

6,731

 

 

 

7,836

 

Lease liability

 

 

16,348

 

 

 

17,925

 

Other

 

 

1,026

 

 

 

788

 

Total deferred tax assets

 

 

399,335

 

 

 

374,092

 

Deferred tax liabilities:

 

 

 

 

 

 

Depreciation

 

 

(2,623

)

 

 

(2,212

)

Right-of-use assets

 

 

(8,738

)

 

 

(9,796

)

Total deferred tax liabilities

 

 

(11,361

)

 

 

(12,008

)

Net of deferred tax assets and liabilities

 

 

387,974

 

 

 

362,084

 

Valuation allowance

 

 

(387,974

)

 

 

(362,084

)

Net deferred tax assets

 

$

 

 

$

 

 

Income taxes paid or refunded consist of the following as of:

 

 

 

Years Ended
December 31,

 

 

 

2025

 

 

2024

 

Federal

 

$

 

 

$

 

State

 

 

1,600

 

 

 

1,700

 

Total income taxes paid (refunded)

 

$

1,600

 

 

$

1,700

 

 

A valuation allowance of $388.0 million and $362.1 million at December 31, 2025 and 2024, respectively, has been established to offset the deferred tax assets, as realization of such assets is uncertain.

At December 31, 2025, the Company had federal and state net operating loss (NOL) carryforwards of $879.1 million and $773.3 million, respectively, which may be available to offset future taxable income. The federal and California NOL carryforwards begin to expire in 2027 and 2028, respectively, unless previously utilized. At December 31, 2025, the Company had federal and California research and development (R&D) credit carryforwards of $48.5 million and $40.1 million, respectively. The federal R&D tax credit carryforwards will begin to expire in 2035 unless previously utilized. The California R&D credit carryforwards will carry forward indefinitely.

Under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, (the Code), substantial changes in the Company’s ownership may limit the amount of net operating loss and research and development credit carryforwards that could be used annually in the future to offset taxable income. The tax benefits related to future utilization of federal and state net operating loss carryforwards, credit carryforwards, and other deferred tax assets may be limited or lost if cumulative changes in ownership exceeds 50% within any three-year period. The Company completed a study to assess whether an ownership change, as defined by Section 382 of the Code, had occurred from the Company’s formation through December 31, 2015. Based upon this study, the Company determined that several ownership changes had occurred. Accordingly, the Company reduced its deferred tax assets related to the federal NOL carryforwards and the federal R&D credit carryforwards that are anticipated to expire unused as a result of these ownership changes. These tax attributes were excluded from deferred tax assets with a corresponding reduction of the valuation allowance with no net effect on income tax expense or the effective tax rate. The Company updated the study December 31, 2025 and concluded there were no ownership changes during 2025. Future ownership changes may further limit the Company’s ability to utilize its remaining tax attributes.

The Company files income tax returns in the United States, various state jurisdictions, and the Netherlands with varying statutes of limitations. The Company currently has no years under examination by any jurisdiction; however, the Company is subject to income tax examination by federal and state tax authorities for years beginning in 2022 and 2021, respectively. However, to the extent allowed by law, the taxing authorities may have the right to examine prior periods where NOLs and tax credits were generated and carried forward, and make adjustments up to the amount of the carryforwards.

The change in the Company’s unrecognized tax benefits is summarized as follows (in thousands):

 

 

December 31,

 

 

2025

 

 

2024

 

 

Beginning unrecognized tax benefits

 

$

70,505

 

 

$

59,680

 

 

Increase related to current year tax positions

 

 

11,630

 

 

 

10,345

 

 

Increase related to prior year tax positions

 

 

275

 

 

 

687

 

 

Decrease related to prior year tax positions

 

 

 

 

 

(207

)

 

Ending unrecognized tax benefits

 

$

82,410

 

 

$

70,505

 

 

 

Due to the valuation allowance recorded against the Company’s deferred tax assets, none of the total unrecognized tax benefits as of December 31, 2025 would reduce the effective tax rate if recognized. The Company has not recognized interest or penalties in its consolidated statements of operations and comprehensive loss since inception. The Company recognizes interest and penalties related to unrecognized tax benefits within income tax expense. The Company has not recognized interest or penalties related to income tax matters in its consolidated statements of operations and comprehensive loss since inception.

Historical Timeline

Fiscal YearFiled
2025Feb 26, 2026Showing above
2023Feb 26, 2024
2022Feb 28, 2023
2021Feb 28, 2022
2020Feb 24, 2021
2019Mar 2, 2020
2017Mar 5, 2018
2015Mar 3, 2016

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.