v3.26.1
Income Taxes (Tables)
12 Months Ended
Dec. 31, 2025
Income Taxes  
Schedule of Pretax book income (loss), as per geographical location

Income before income taxes included the following (in thousands):

  ​ ​ ​

As of December 31, 2025

  ​ ​ ​

As of December 31, 2024

Pretax book income/(loss)

 

  ​

 

  ​

United States

$

(56,511)

$

(77,193)

United Kingdom

 

(6,378)

 

(5,541)

Germany

 

 

(1,008)

Netherlands

 

119

 

(35)

Pretax book loss

$

(62,770)

$

(83,777)

Schedule of Deferred Tax Assets and Liabilities

The tax effects of temporary differences and tax loss and credit carry forwards that give rise to significant portions of deferred tax assets and liabilities at December 31, 2025 and 2024 are comprised of the following (in thousands):

  ​ ​ ​

As of December 31, 2025

  ​ ​ ​

As of December 31, 2024

Deferred tax asset

Net operating loss carryforward

$

236,137

$

222,329

Research and development credit carry forwards

19,746

18,687

Capitalized research and experimental expenditures

24,835

23,496

Stock based compensation

16,856

17,116

Intangible assets

(12,970)

38

Other

12

(407)

Total deferred tax assets

284,616

281,221

Valuation Allowance

(297,787)

(281,221)

Deferred tax liability, net of allowance

$

(13,171)

$

Schedule of Effective Income Tax Rate Reconciliation

The expected tax expense (benefit) based on the U.S. federal statutory rate is reconciled with actual tax expense (benefit) as follow (dollars in thousands):

  ​ ​ ​

As of December 31, 2025

  ​ ​ ​

As of December 31, 2024

 

$

Amount

  ​ ​ ​

Percent

%

$

Amount

  ​ ​ ​

Percent

%

Statutory federal income tax rate

 

(13,182)

21.0

%  

(17,593)

21.0

%  

State taxes, net of federal tax benefit (a)

 

0.0

%  

(456)

5.8

%  

Foreign tax effect

 

Rate differential

 

(279)

0.4

%  

170

-0.2

%  

Rate change

 

(475)

0.8

%  

0.0

%  

Change in valuation allowance

 

1,532

-2.4

%  

1,213

-1.4

%  

Nontaxable or nondeductible items

 

Interest on convertible debt

 

1,015

-1.6

%  

648

-0.8

%  

Debt extinguishment on convertible debt

2,403

-3.8

%  

2,125

-2.5

%  

Mark-to-market gain on convertible debt

(5,383)

8.6

%  

(1,620)

1.9

%  

Other permanent items and true ups

(490)

0.8

%  

13

0.0

%  

Tax credits

Research & development tax credits

(468)

0.7

%  

(464)

0.6

%  

Change in unrecognized tax benefit

0.0

%  

0.0

%  

Change in valuation allowance

 

14,790

-23.6

%  

15,964

-19.1

%  

Income tax provision (benefit)

 

(537)

0.9

%  

0.0

%  

(a)State taxes in Maryland made up the majority (greater than 50 percent) of the tax effect in this category.

Schedule of Components of Income Tax Expense (Benefit)

  ​ ​ ​

As of December 31, 2025

  ​ ​ ​

As of December 31, 2024

Federal

 

  ​

 

  ​

Current

$

$

Deferred

 

(12,733)

 

(13,994)

State

 

 

Current

 

 

Deferred

 

(6,832)

 

(4,364)

Foreign

 

 

Current

 

(497)

 

Deferred

 

2,959

 

(1,418)

Change in valuation allowance

 

16,566

 

19,776

Income tax provision (benefit)

$

(537)

$