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Stock Based Compensation (Tables)

12 Months Ended

Dec. 31, 2025

Stock Based Compensation

Schedule of option activity under the Plan

​

​	​	​	​	​	​	​	​	​	​
​	​	​	​	​	​	​	Weighted-average	​	​
​	​	​	​	​	​	​	Remaining	​	​
​	​	Number of	​	Weighted-average		​	Contractual Term	​	Aggregate
Stock Options	​ ​ ​	Stock Options	​ ​ ​	Exercise Price		​ ​ ​	(in years)	​	Intrinsic Value
Outstanding as of January 1, 2025	​	20,605,693	​	$	2.45	​	6.68	​	12,008
Granted	​	—	​	$	—	​	​	​	​
Exercised	​	(3,339,162)	​	$	1.57	​	​	​	​
Forfeited	​	(2,549,167)	​	$	2.58	​	​	​	​
Expired	​	(2,397,290)	​	$	4.97	​	​	​	​
Outstanding as of December 31, 2025	​	12,320,074	​	$	2.13	​	5.59	​	29,496
​	​	​	​	​	​	​	​	​	​
Exercisable as of December 31, 2024	​	12,275,078	​	$	2.48	​	5.27	​	9,427
Exercisable as of December 31, 2025	​	9,769,633	​	$	2.19	​	4.94	​	23,427

Schedule of restricted stock grants to non employees

​

​	​	​	​	​	​	​
​	​	For the Years Ended December 31,
​	​ ​ ​	2025		​ ​ ​	2024
Restricted stock grants to Dahae Executives	​	​	—	​	​	298,508

Schedule of recognized & allocated compensation costs

​

​	​	​	​	​	​	​
​	​	For the Years Ended December 31,
​	​	2025		​ ​ ​	2024
Stock-based compensation costs related to RSUs	​	$	6,344	​	$	5,662
Stock-based compensation costs related to stock options	​		2,319	​		6,138
Stock-based compensation costs related to the ESPP	​	​	327	​	​	172
Total equity-based compensation costs	​	$	8,990	​	$	11,972

​

​	​	​	​	​	​	​
​	​	For the Years Ended December 31,
​	​	2025			2024
Direct costs	​	$	—	​	$	1,131
Research and development	​	​	3,553	​	​	4,463
Selling, general and administrative	​	​	5,437	​	​	6,378
Total equity-based compensation cost	​	$	8,990	​	$	11,972

Schedule of fair value of each option using the Black-Scholes option pricing model

​

​	​	​	​	​
​	​	​	​	​
​	​	2024
Approximate risk‑free rate	​	​	4.23	%
Volatility	​	​	48.1	%
Average expected life (in years)	​	​	6	​
Dividend yield	​	​	0	%
Weighted‑average grant date fair value	​	$	0.82	​
Estimated fair value of total stock options granted	​	$	5,175	​

Restricted stock units (RSUs)

Stock Based Compensation

Schedule of non-vested Restricted stock units

​

​	​	​	​	​	​
​	​	Number of	​ ​ ​	Weighted-average
​	​	RSUs	​	Grant Date Fair Value
Balance at December 31, 2024	​	8,200,553	​	​	3.10
Granted	​	10,151,545	​	​	1.75
Vested or Exercised	​	(3,008,674)	​	​	2.02
Forfeited	​	(2,015,234)	​	​	2.08
Balance at December 31, 2025	​	13,328,190	​	​	1.78

Restricted stock

Stock Based Compensation

Schedule of non-vested Restricted stock units

​

​	​	​	​	​
​	​	Number of	​ ​ ​	Weighted-average
​	​	Restricted Stock Grants	​	Grant Date Fair Value
Balance at December 31, 2024	​	238,806	​	1.23
Granted	​	—	​	​
Vested	​	(110,671)	​	1.23
Forfeited	​	—	​	​
Balance at December 31, 2025	​	128,135	​	1.23

2021 Equity Incentive Plan

Stock Based Compensation

Schedule of option activity under the Plan

​

​	​	​	​	​	​	​
​	​	For the Years Ended December 31,
​	​ ​ ​	2025		​ ​ ​	2024
Option awards granted under 2021 Plan	​	​	—	​	​	6,324,127
RSU awards granted under 2021 Plan	​	​	10,151,545	​	​	6,792,700

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