| Stock-based compensation |
Note 35.Stock-based compensation Employee stock option plans The F Share Option Plan (“FSOP”) and the Ordinary Share Option Plan (“OSOP”) were approved respectively on January 19, 2023, and September 15, 2023, by the Board of directors of SEALSQ. Grants In the 12 months to December 31, 2023, the Group granted a total of 77 options exercisable in F shares to employees, with immediate vesting, all of which had been exercised as of December 31, 2024. The new shares resulting from the exercise were only created in 2025, therefore, the share capital increase from this exercise was not recorded in the year ended December 31, 2024. The options granted were valued at grant date using the Black-Scholes model. There was no grant of options on ordinary shares under the ESOP in the year ended December 31, 2023. In the 12 months to December 31, 2024, the Group granted a total of 23 options exercisable in F shares to employees, with immediate vesting, all of which had been exercised as of December 31, 2024. The new shares resulting from the exercise were only created in 2025, therefore, the share capital increase from this exercise was not recorded in the year ended December 31, 2024. The Group also granted a total of 245,165 options exercisable in ordinary shares to Board members, with immediate vesting granted, none of which had been exercised as of December 31, 2024. The options granted were valued at grant date using the Black-Scholes model. In the 12 months to December 31, 2025, the Group granted a total of 3,042,652 options exercisable in ordinary shares to employees, board members and advisors. The options granted consisted of: | - | 3,041,452 options with immediate vesting granted to employees, Board members and advisors, 2,569,953 of which had been exercised as of December 31, 2025; and |
| - | 1,200 options exercisable in ordinary shares to an employee, not yet vested as of December 31, 2025. |
The options granted were valued at grant date using the Black-Scholes model. There was no grant of options on F shares under the ESOP in the year ended December 31, 2025. Stock option charge to the income statement The Group calculates the fair value of options granted by applying the Black-Scholes option pricing model. Expected volatility was based on historical volatility of SEALSQ’s ordinary shares in 2025 and 2024, and on historical share price volatility of other companies in the same industry and of a similar size for prior periods. In the year ended December 31, 2025, a total charge of USD 11,260,701 for options granted to Board members, employees and advisors was recognized in the consolidated income statement calculated by applying the Black-Scholes model at grant, in relation to options. The following assumptions were used to calculate the compensation expense and the calculated fair value of stock options granted: | | | | | | | | | | December 31, | | December 31, | | December 31, | | Assumption | | 2025 | | 2024 | | 2023 | | Dividend yield | | None | | None | | None | | Risk-free interest rate used (average) | | 1.00 | % | 1.00 | % | 1.00 | % | Expected market price volatility | | 175.40 - 183.25 | % | 65.31 - 140.47 | % | 73.19 | % | Average remaining expected life of stock options on F shares (years) | | — | | — | | 6.19 | | Average remaining expected life of stock options on ordinary shares (years) | | 5.33 | | 6.53 | | n/a | |
The following tables illustrates the development of the Group’s non-vested options for the years ended December 31, 2025 and 2024. | | | | | | | Options on ordinary shares | | | Number of shares | | Weighted-average grant | Non-vested options | | under options | | date fair value (USD) | Non-vested options as at December 31, 2023 | | — | | — | Granted | | 245,165 | | 0.61 | Vested | | 245,165 | | 0.61 | Non-vested forfeited or cancelled | | — | | — | Non-vested options as at December 31, 2024 | | — | | — | Granted | | 3,042,652 | | 2.94 | Vested | | 3,041,452 | | 2.93 | Non-vested forfeited or cancelled | | — | | — | Non-vested options as at December 31, 2025 | | 1,200 | | 4.29 |
| | | | | | | Options on F shares | | | Number of shares | | Weighted-average grant | Non-vested options | | under options | | date fair value (USD) | Non-vested options as at December 31, 2023 | | — | | — | Granted | | 23 | | 2.35 | Vested | | 23 | | 2.35 | Non-vested forfeited or cancelled | | — | | — | Non-vested options as at December 31, 2024 | | — | | — | Granted | | — | | — | Vested | | — | | — | Non-vested forfeited or cancelled | | — | | — | Non-vested options as at December 31, 2025 | | — | | — |
The following tables summarize the Group’s stock option activity for the years ended December 31, 2025 and 2024. | | | | | | | | | | | | | | | Weighted average | | | | | | | Weighted-average | | remaining | | Aggregate | | | Ordinary shares | | exercise price | | contractual term | | intrinsic value | Options on ordinary shares | | under options | | (USD) | | (in years) | | (USD) | Outstanding as at December 31, 2023 | | — | | — | | — | | — | Of which vested | | — | | — | | — | | — | Granted | | 245,165 | | 0.01 | | — | | — | Outstanding as at December 31, 2024 | | 245,165 | | 0.01 | | 6.65 | | 1,505,313 | Of which vested | | 245,165 | | 0.01 | | 6.65 | | 1,505,313 | Granted | | 3,042,652 | | 0.01 | | — | | — | Exercised or converted | | (2,647,019) | | 0.01 | | — | | 9,471,366 | Forfeited or cancelled | | (65,774) | | 0.01 | | — | | | Outstanding as at December 31, 2025 | | 575,024 | | 0.04 | | 6.14 | | 2,152,900 | Of which vested | | 573,824 | | 0.04 | | 6.14 | | 2,148,376 |
| | | | | | | | | | | | | | | Weighted average | | | | | | | Weighted-average | | remaining | | Aggregate | | | F shares under | | exercise price | | contractual term | | intrinsic value | Options on F shares | | options | | (USD) | | (in years) | | (USD) | Outstanding as at December 31, 2023 | | 77 | | 0.05 | | 6.19 | | 19 | Of which vested | | 77 | | 0.05 | | 6.19 | | 19 | Granted | | 23 | | 0.05 | | — | | — | Exercised or converted | | (100) | | 0.05 | | — | | 118 | Outstanding as at December 31, 2024 | | — | | — | | — | | — | Of which vested | | — | | — | | — | | — | Granted | | — | | — | | — | | — | Exercised or converted | | — | | — | | — | | — | Outstanding as at December 31, 2025 | | — | | — | | — | | — | Of which vested | | — | | — | | — | | — |
Summary of stock-based compensation expenses | | | | | | | Stock-based compensation expenses | | 12 months ended December 31, | USD’000 | | 2025 | | 2024 | | 2023 | In relation to the Ordinary Share Option Plan | | 11,261 | | 148 | | — | In relation to the F Share Option Plan | | — | | — | | — | Total | | 11,261 | | 148 | | — |
Stock-based compensation expenses are recorded under the following expense categories in the income statement. | | | | | | | Stock-based compensation expenses | | 12 months ended December 31, | USD’000 | | 2025 | | 2024 | | 2023 | Research & development expenses | | 2,376 | | — | | — | Selling & marketing expenses | | 3,694 | | — | | — | General & administrative expenses | | 5,191 | | 148 | | — | Total | | 11,261 | | 148 | | — |
The following table reconciles the total stock-based compensation expense to the amounts recognized in stockholders’ equity: | | | | | | | Stock-based compensation expenses | | 12 months ended December 31, | USD’000 | | 2025 | | 2024 | | 2023 | Total stock-based compensation for the period | | 11,261 | | 148 | | — | Less: stock-based compensation classified as liability | | (1,538) | | — | | — | Stock-based compensation recognized in APIC | | 9,723 | | 148 | | — |
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