The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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The amount of short-term deposits held by the entity that are not classified as cash equivalents. [Refer: Cash equivalents]

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Amount of additional proceeds receivable upon exercise of warrants.

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Accounting principles - Going concern (Details) - EUR (€) € in Thousands	Dec. 31, 2025	May 07, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Going Concern
Cash and cash equivalents	€ 99,312		€ 96,564	€ 26,918	€ 86,736
Short-term deposits	131,558		€ 0	€ 70
Tranche II, 2024 Financing arrangement in three tranches \| Maximum \| T3 BSA warrants
Going Concern
Additional proceeds receivable upon exercise of warrants	€ 116,000	€ 116,000