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Income Taxes (Tables)

12 Months Ended

Dec. 31, 2025

Income Taxes

Schedule of Income before income tax of domestic and foreign

​

​	​	​	​	​	​	​
​	​	For the Years Ended December 31,
​	​ ​ ​	2025		​	2024
U.S.	​	$	(86,277)	​	$	(93,543)
Foreign	​	​	(7,206)	​	​	(1,650)
Loss before income tax expense (benefit)	​	$	(93,483)	​	$	(95,193)

Schedule of income taxes

​

​	​	​	​	​	​	​	​
​	​	For the Years Ended December 31,					​
​	​ ​ ​	2025		​	2024		​
Current income tax expense (benefit)	​	​	​	​	​	​	​
Federal	​	$	—	​	$	—	​
State	​	​	(1)	​	​	8	​
Foreign	​	​	(7)	​	​	1,186	​
Deferred income tax expense (benefit)	​	​	​	​	​	​	​
Federal	​	​	—	​	​	—	​
State	​	​	—	​	​	—	​
Foreign	​	​	—	​	​	—	​
Total income tax expense (benefit)	​	$	(8)	​	$	1,194	​

Schedule of net cash paid

​

​	​	​
​	For the Year Ended December 31,
​	2025
Federal	$	—
Aggregated state and local jurisdictions	​	—
Disaggregated state and local jurisdictions	​	​
South Carolina	​	3
District of Columbia	​	2
California	​	2
Connecticut	​	1
Foreign (Republic of Korea)	​	(8)
Net cash paid (refunds received) for income taxes	$	—

Schedule of reconciliation of the statutory federal income tax expense to income tax

​

​	​	​	​	​	​
​	​ ​ ​	December 31,			​
​	​ ​ ​	2025	​	2025	​
​	​	Tax Expense	​	Effective Rate	​
U.S. federal statutory tax rate	​	(19,552)	​	21	%
​	​	​	​	​	​
State income taxes - net of federal income tax benefits (1)	​	(2)	​	—	%
Foreign tax effects	​	​	​	​	​
Republic of Korea	​	​	​	​	​
Valuation allowance	​	2,400	​	(2.58)	%
Other	​	(845)	​	0.91	%
Effects of changes in tax laws or rates enacted in the current period	​	—	​	—	​
Effect of cross-border tax laws	​	—	​	—	%
Tax credits	​	​	​	​	​
Research and development credit	​	(903)	​	0.97	%
Changes in valuation allowances	​	16,772	​	(18.01)	%
Nontaxable or nondeductible items	​	​	​	​	​
Stock-based compensation (2)	​	(429)	​	0.46	%
Mark-to-market warrant liabilities	​	1,081	​	(1.16)	%
Other	​	667	​	(0.72)	%
Changes in unrecognized tax benefits	​	226	​	(0.24)	%
Other adjustments	​	577	​	(0.62)	​
Effective tax rate	​	(8)	​	0.01	%

​

(1) South Carolina and the District of Columbia make up the majority (greater than 50%) of the state income tax expense, net of federal income tax effect category.

(2) The Company classifies windfalls and shortfalls relating to stock-based compensation as a nontaxable or nondeductible item.

​

The table below represents a reconciliation of the U.S. federal statutory tax rate to effective tax rate for the year ended December 31, 2024 under the prior guidance

​

​	​	​	​
U.S. federal statutory tax rate	​	21.00	%
State income taxes - net of federal income tax benefits	​	0.82	%
Foreign withholding taxes	​	(1.25)	%
Global tax rate differential	​	(0.21)	%
Permanent differences	​	(2.17)	%
Net change in valuation allowance	​	(21.79)	%
Research and development	​	4.08	%
Other	​	(1.74)	%
Effective tax rate	​	(1.26)	%

​

​

Schedule of tax effects of temporary differences that give rise to significant portions of the deferred income tax assets and liabilities

​

​	​	​	​	​	​	​	​
​	​	December 31,		​	December 31,		​
​	​ ​ ​	2025		​	2024		​
Deferred tax assets	​	​	​	​	​	​	​
Net operating loss	​	$	51,517	​	$	30,446	​
R&D credit	​	​	8,100	​	​	7,423	​
Stock compensation	​	​	3,363	​	​	2,909	​
Section 174 capitalization	​	​	26,203	​	​	22,759	​
ROU lease liability	​	​	2,018	​	​	2,061	​
Available-for-sale securities	​	​	—	​	​	(14)	​
Other	​		1,670	​		2,441	​
Total deferred tax asset	​		92,871	​		68,025	​
Valuation allowance	​		(90,181)	​		(64,744)	​
Net deferred tax assets	​		2,690	​		3,281	​
Deferred tax liabilities	​		​	​		​	​
Intangibles (non-goodwill)	​	$	(4)	​	$	(2)	​
Available-for-sale securities	​	​	(82)	​	​	—	​
Property, plant and equipment	​		(663)	​		(1,144)	​
Accretion	​	​	(236)	​	​	(307)	​
ROU asset	​	​	(1,705)	​	​	(1,828)	​
Total deferred tax liabilities	​		(2,690)	​		(3,281)	​
Total net deferred tax liability	​	$	—	​	$	—	​

Schedule of operating losses and tax credit carryforwards

​

​	​	​	​	​
​	​	Amount	​	Expiration Years
Net operating losses, federal (Pre January 1, 2018)	$	99	​	2037
Net operating losses, federal (Post December 31, 2017)	​	42,242	​	Indefinite
Net operating losses, state	​	6,889	​	Various
Net operating losses, foreign	​	2,287	​	2039-2040
Tax Credits, federal	​	8,100	​	2037-2045

Schedule of unrecognized tax benefits

​

​	​	​	​	​	​	​	​
​	​	For the Year Ended December 31,					​
​	​ ​ ​	2025		​	2024		​
Balance, beginning of year	​	$	2,474	​	$	1,186	​
Gross increases related to prior period tax position	​		—	​		383	​
Gross increases related to current period tax position	​		566	​		905	​
Gross decreases related to prior period tax position	​		(340)	​		—	​
Balance, end of year	​	$	2,700	​	$	2,474	​

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