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v3.25.4

Stock-Based Compensation (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Schedule of stock-based compensation included in its condensed consolidated statements of operations and comprehensive income (loss) | ​
​ | ​ | ​ | ​ | ​ | ​
​ | Years Ended December 31,
(in thousands) | 2025 | ​ ​ ​ | 2024
Research and development | $ | 3,037 | ​ | $ | 8,021
General and administrative |  | 7,595 | ​ | ​ | 11,896
Cost of revenue |  | 339 | ​ | ​ | 18
Total | $ | 10,971 | ​ | $ | 19,935
Schedule of share-based compensation expense by award type | ​
​ | ​ | ​ | ​ | ​ | ​
​ | Years Ended December 31,
(in thousands) | 2025 | ​ ​ ​ | 2024
RSUs | $ | 8,359 | ​ | $ | 12,733
PSUs | ​ | 1,380 | ​ | ​ | 2,885
RSAs | ​ | 1,199 | ​ | ​ | 1,950
Stock options | ​ | 33 | ​ | ​ | 370
Earn-Out Restricted Shares | ​ | — | ​ | ​ | 1,997
Total | $ | 10,971 | ​ | $ | 19,935
Summary of RSU activity | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Number of Shares | ​ | Weighted Average Fair Value
Outstanding at December 31, 2023 | ​ | 6,359,474 | ​ | $ | 3.71
Granted | ​ | 11,729,289 | ​ | $ | 1.32
Vested | ​ | (2,413,455) | ​ | $ | 4.14
Forfeited and canceled | ​ | (2,392,385) | ​ | $ | 1.95
Outstanding at December 31, 2024 | ​ | 13,282,923 | ​ | $ | 1.83
Granted | ​ | 9,029,793 | ​ | $ | 0.75
Gross vested units | ​ | (5,209,010) | ​ | $ | 2.40
Forfeited and canceled | ​ | (3,219,825) | ​ | $ | 1.31
Outstanding at December 31, 2025 | ​ | 13,883,881 | ​ | $ | 1.03
Summary of fair value assumptions for performance stock units | ​
​ | ​ | ​
​ | ​ ​ ​ | 2024
Expected term (in years) | ​ | 3.0
Risk free rate | ​ | 4.06%
Expected volatility | ​ | 90.0%
Expected dividends | ​ | 0%
Stock price | $ | 1.36
Summary of PSU activity | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Number of Shares | ​ | Weighted Average Fair Value
Outstanding at December 31, 2023 | ​ | 3,364,810 | ​ | $ | 3.60
Granted | ​ | 3,637,556 | ​ | $ | 0.42
Vested | ​ | — | ​ | $ | —
Forfeited and canceled | ​ | (1,029,316) | ​ | $ | 6.96
Outstanding at December 31, 2024 | ​ | 5,973,050 | ​ | $ | 1.34
Granted | ​ | 264,469 | ​ | $ | 2.32
Vested | ​ | — | ​ | $ | —
Forfeited and canceled | ​ | (274,365) | ​ | $ | 1.31
Outstanding at December 31, 2025 | ​ | 5,963,154 | ​ | $ | 1.39
Summary of stock option activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Number of Options | ​ | ​ | Weighted Average Exercise Price | ​ | ​ | Weighted Average Remaining Contractual Term (in years) | ​ | ​ | Aggregate Intrinsic Value (in millions)
Outstanding at December 31, 2023 | ​ | 13,619,793 | ​ | $ | 0.17 | ​ | ​ | 6.8 | ​ | $ | 22.7
Granted | ​ | — | ​ | $ | — | ​ | ​ | ​ | ​ | ​ | ​
Exercised | ​ | (6,507,475) | ​ | $ | 0.16 | ​ | ​ | ​ | ​ | $ | 4.0
Forfeited and canceled | ​ | (1,049,208) | ​ | $ | 0.19 | ​ | ​ | ​ | ​ | ​ | ​
Outstanding at December 31, 2024 | ​ | 6,063,110 | ​ | $ | 0.19 | ​ | ​ | 5.5 | ​ | $ | 12.2
Granted | ​ | — | ​ | $ | — | ​ | ​ | ​ | ​ | ​ | ​
Exercised | ​ | (614,255) | ​ | $ | 0.12 | ​ | ​ | ​ | ​ | $ | 0.9
Forfeited and canceled | ​ | (17,130) | ​ | $ | 0.39 | ​ | ​ | ​ | ​ | ​ | ​
Outstanding at December 31, 2025 | ​ | 5,431,725 | ​ | $ | 0.19 | ​ | ​ | 4.7 | ​ | $ | 8.8
Vested, December 31, 2025 | ​ | 5,431,725 | ​ | $ | 0.19 | ​ | ​ | 4.7 | ​ | $ | 8.8
Vested or expected to vest, December 31, 2025 | ​ | 5,431,725 | ​ | $ | 0.19 | ​ | ​ | 4.7 | ​ | $ | 8.8
Restricted Stock |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Summary of restricted share activity | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Number of Shares | ​ | Weighted Average Fair Value
Outstanding at December 31, 2023 | ​ | 649,567 | ​ | $ | 5.05
Granted | ​ | — | ​ | $ | -
Vested | ​ | (386,964) | ​ | $ | 5.05
Forfeited and canceled | ​ | (7,145) | ​ | $ | 5.07
Outstanding at December 31, 2024 | ​ | 255,458 | ​ | $ | 5.04
Granted | ​ | — | ​ | $ | —
Vested | ​ | (253,358) | ​ | $ | 5.04
Forfeited and canceled | ​ | (2,100) | ​ | $ | 5.30
Outstanding at December 31, 2025 | ​ | — | ​ | $ | —
Earn-out Shares, Earn-out Restricted Shares |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Summary of restricted share activity | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Number of Shares | ​ | Weighted Average Fair Value
Outstanding at December 31, 2023 | ​ | 1,619,998 | ​ | $ | 6.53
Granted/vested | ​ | — | ​ | $ | —
Forfeited and canceled | ​ | (854,008) | ​ | $ | 6.53
Outstanding at December 31, 2024 | ​ | 765,990 | ​ | $ | 6.53
Granted/vested | ​ | — | ​ | $ | —
Forfeited and canceled | ​ | (23,710) | ​ | $ | 6.53
Outstanding at December 31, 2025 | ​ | 742,280 | ​ | $ | 6.53

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