Shareholders' equity - Movements in BSPCE and BSA share warrants (Details) |
12 Months Ended | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 15, 2023
EquityInstruments
€ / shares
|
May 25, 2023
EquityInstruments
€ / shares
|
Apr. 16, 2021
EquityInstruments
€ / shares
|
Mar. 09, 2020
EquityInstruments
€ / shares
|
Jun. 28, 2019
EquityInstruments
€ / shares
|
May 29, 2017
EquityInstruments
€ / shares
|
Dec. 31, 2025
EquityInstruments
€ / shares
shares
|
Dec. 31, 2025
EUR (€)
EquityInstruments
€ / shares
shares
|
Dec. 31, 2025
EquityInstruments
€ / shares
shares
|
Dec. 31, 2024
EquityInstruments
€ / shares
shares
|
Dec. 31, 2024
EUR (€)
EquityInstruments
€ / shares
shares
|
Dec. 31, 2024
EquityInstruments
€ / shares
shares
|
Dec. 31, 2023
EquityInstruments
€ / shares
shares
|
Dec. 31, 2023
EUR (€)
EquityInstruments
€ / shares
shares
|
Dec. 31, 2023
EquityInstruments
€ / shares
shares
|
|
| Shareholders' equity | |||||||||||||||
| Outstanding, Beginning balance | 1,410,814 | 790,600 | |||||||||||||
| Issued | 1,060,000 | ||||||||||||||
| Exercised | (363,000) | ||||||||||||||
| Forfeited / Lapsed | (76,786) | ||||||||||||||
| Outstanding, Ending balance | 0 | 1,410,814 | |||||||||||||
| BSPCE and BSA Share Warrants | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Outstanding, Beginning balance | 776,333 | 776,333 | 806,800 | ||||||||||||
| Issued | 30,000 | ||||||||||||||
| Forfeited / Lapsed | (60,467) | ||||||||||||||
| Outstanding, Ending balance | 776,333 | 776,333 | 776,333 | ||||||||||||
| Number of exercisable shares | 746,333 | 746,333 | 746,333 | 746,333 | 746,333 | 746,333 | 732,000 | 732,000 | 732,000 | ||||||
| Number of shares callable by warrants | shares | 776,333 | 776,333 | 776,333 | 776,333 | 776,333 | 776,333 | 776,333 | 776,333 | 776,333 | ||||||
| Expense from share-based payment transactions | € | € 30,000 | € 236,000 | € 827,000 | ||||||||||||
| BSPCE plans | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Outstanding, Beginning balance | 430,000 | 430,000 | 488,800 | ||||||||||||
| Forfeited / Lapsed | (58,800) | ||||||||||||||
| Outstanding, Ending balance | 430,000 | 430,000 | 430,000 | ||||||||||||
| Number of exercisable shares | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | ||||||
| Number of shares callable by warrants | shares | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | ||||||
| BSPCE - Plan 2013 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 0.59 | € 0.59 | € 0.59 | € 0.59 | € 0.59 | € 0.59 | |||||||||
| Outstanding, Beginning balance | 8,800 | ||||||||||||||
| Forfeited / Lapsed | (8,800) | ||||||||||||||
| Number of bonus shares lapsed | 8,800 | ||||||||||||||
| BSPCE - Plan 2021 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | |||||
| Outstanding, Beginning balance | 430,000 | 430,000 | 480,000 | ||||||||||||
| Issued | 600,000 | ||||||||||||||
| Forfeited / Lapsed | (50,000) | ||||||||||||||
| Outstanding, Ending balance | 430,000 | 430,000 | 430,000 | ||||||||||||
| Number of exercisable shares | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | 430,000 | ||||||
| BSPCE - Plan 2021 | Based on Market Condition | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Forfeited / Lapsed | (30,000) | ||||||||||||||
| BSPCE - Plan 2021 | Based on Non-Market Condition | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Forfeited / Lapsed | (20,000) | ||||||||||||||
| BSA Plans | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Outstanding, Beginning balance | 346,333 | 346,333 | 318,000 | ||||||||||||
| Issued | 30,000 | ||||||||||||||
| Forfeited / Lapsed | (1,667) | ||||||||||||||
| Outstanding, Ending balance | 346,333 | 346,333 | 346,333 | ||||||||||||
| Number of exercisable shares | 316,333 | 316,333 | 316,333 | 316,333 | 316,333 | 316,333 | 302,000 | 302,000 | 302,000 | ||||||
| Number of shares callable by warrants | shares | 346,333 | 346,333 | 346,333 | ||||||||||||
| BSA - Plan 2017 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 6.675 | € 6.67 | € 6.67 | € 6.67 | € 6.67 | € 6.67 | € 6.67 | € 6.67 | € 6.67 | € 6.67 | |||||
| Outstanding, Beginning balance | 130,000 | 130,000 | 130,000 | ||||||||||||
| Issued | 195,000 | ||||||||||||||
| Outstanding, Ending balance | 130,000 | 130,000 | 130,000 | ||||||||||||
| Number of exercisable shares | 130,000 | 130,000 | 130,000 | 130,000 | 130,000 | 130,000 | 130,000 | 130,000 | 130,000 | ||||||
| BSA - Plan 2018 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 6.07 | € 6.07 | € 6.07 | € 6.07 | € 6.07 | € 6.07 | € 6.07 | € 6.07 | € 6.07 | ||||||
| Outstanding, Beginning balance | 116,000 | 116,000 | 116,000 | ||||||||||||
| Outstanding, Ending balance | 116,000 | 116,000 | 116,000 | ||||||||||||
| Number of exercisable shares | 116,000 | 116,000 | 116,000 | 116,000 | 116,000 | 116,000 | 116,000 | 116,000 | 116,000 | ||||||
| BSA - 2019 plan | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 2.2 | € 2.2 | € 2.2 | € 2.2 | € 2.2 | € 2.2 | € 2.2 | € 2.2 | € 2.2 | € 2.2 | |||||
| Outstanding, Beginning balance | 10,000 | 10,000 | 10,000 | ||||||||||||
| Issued | 10,000 | ||||||||||||||
| Outstanding, Ending balance | 10,000 | 10,000 | 10,000 | ||||||||||||
| Number of exercisable shares | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | ||||||
| BSA 2019 bis | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | |||||
| Outstanding, Beginning balance | 10,000 | 10,000 | 10,000 | ||||||||||||
| Issued | 10,000 | ||||||||||||||
| Outstanding, Ending balance | 10,000 | 10,000 | 10,000 | ||||||||||||
| Number of exercisable shares | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | ||||||
| BSA 2019 ter | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | € 3.68 | |||||
| Outstanding, Beginning balance | 36,000 | 36,000 | 36,000 | ||||||||||||
| Issued | 36,000 | ||||||||||||||
| Outstanding, Ending balance | 36,000 | 36,000 | 36,000 | ||||||||||||
| Number of exercisable shares | 36,000 | 36,000 | 36,000 | 36,000 | 36,000 | 36,000 | 36,000 | 36,000 | 36,000 | ||||||
| BSA 2021 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | € 11.74 | |||||
| Outstanding, Beginning balance | 14,333 | 14,333 | 16,000 | ||||||||||||
| Issued | 50,000 | ||||||||||||||
| Forfeited / Lapsed | (1,667) | ||||||||||||||
| Outstanding, Ending balance | 14,333 | 14,333 | 14,333 | ||||||||||||
| Number of exercisable shares | 14,333 | 14,333 | 14,333 | 14,333 | 14,333 | 14,333 | |||||||||
| BSA 2021 | Based on Non-Market Condition | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Forfeited / Lapsed | (1,667) | ||||||||||||||
| BSA 2023-1 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 2.51 | € 2.51 | € 2.51 | € 2.51 | € 2.51 | € 2.51 | € 2.51 | € 2.51 | 2.51 | € 2.51 | |||||
| Outstanding, Beginning balance | 10,000 | 10,000 | 10,000 | 10,000 | |||||||||||
| Issued | 10,000 | 10,000 | |||||||||||||
| Outstanding, Ending balance | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | ||||||||||
| BSA 2023-2 | |||||||||||||||
| Shareholders' equity | |||||||||||||||
| Exercise price (in euros) | € / shares | € 3.91 | € 3.91 | € 3.91 | € 3.91 | € 3.91 | € 3.91 | € 3.91 | € 3.91 | € 3.91 | € 3.91 | |||||
| Outstanding, Beginning balance | 20,000 | 20,000 | |||||||||||||
| Issued | 20,000 | 20,000 | |||||||||||||
| Outstanding, Ending balance | 20,000 | 20,000 | 20,000 | ||||||||||||