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Legal value guide
The legal value of electronic signature
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Is an electronic signature valid and enforceable? Yes — and its probative force depends on the signature level. Here's what eIDAS and the Civil Code say, the probative force of each level and admissibility before courts.
Does electronic signature have legal value?
Yes. Article 25 of the eIDAS regulation establishes a principle of non-discrimination: an electronic signature cannot be refused any legal effect or admissibility as evidence solely because it is in electronic form. Under French law, Article 1366 of the Civil Code gives electronic documents the same probative force as paper, subject to reliable identification of the author and conservation guaranteeing integrity.
Article 1367 of the Civil Code specifies that electronic signature consists of the use of a reliable identification process guaranteeing its link to the act. The reliability of this process is presumed when it meets the requirements set by decree — which corresponds to qualified signature (QES).
Probative force according to signature level
eIDAS defines three levels, whose probative force differs:
Simple signature (SES)
Admissible as evidence (art. 25 eIDAS) but without presumption: its value is freely assessed by the judge. Suitable for low-stakes documents.
Advanced signature (AES)
Linked to the signatory, with authentication and audit trail. Its probative force is significantly strengthened; it is the recommended standard for most contracts.
Qualified signature (QES)
Legal equivalent of handwritten signature (art. 25 eIDAS). It benefits from the presumption of reliability of Article 1367 of the Civil Code: the burden of proof is reversed in case of dispute.
Admissibility and evidence before courts
In practice, several principles govern the use of electronic signature as evidence:
Non-discrimination: evidence cannot be excluded solely because it is electronic (art. 25 eIDAS).
Probative force: equivalent to paper if the author is reliably identified and integrity is guaranteed (art. 1366 Civil Code).
Presumption of reliability: reserved for qualified signature (QES) meeting the decree (art. 1367 para. 2).
Burden of proof: for SES and AES, it is up to the party relying on it to demonstrate reliability; the audit trail is then decisive.
Evidence file: timestamp, identity, IP and OTP strengthen enforceability regardless of level.
How to guarantee the legal value of your signatures
To maximize probative force, choose the level appropriate to the stakes (AES for most contracts, QES for the most sensitive acts) and systematically preserve the evidence file. With Certyneo, each signature comes with authentication, timestamping and a complete audit trail.
The signed document and its eIDAS evidence file are archived with probative value. In case of dispute, you have objective evidence (identity, integrity, date) that supports admissibility and the strength of proof.
Frequently asked questions
Is electronic signature legally valid?
Yes. It cannot be denied legal effect or admissibility as evidence on the ground that it is electronic (art. 25 eIDAS), and electronic writing has the same probative force as paper under conditions (art. 1366 Civil Code).
Which signature has the strongest legal value?
Qualified signature (QES): it is the legal equivalent of a handwritten signature and benefits from a presumption of reliability (art. 1367 Civil Code). Advanced signature (AES) remains very solid for most uses.
Is electronic signature admissible in court?
Yes, it is admissible as evidence. For SES and AES, its value is assessed in light of the reliability of the process (audit trail, time stamp); for QES, a presumption of reliability applies.
Who must prove the reliability of the signature in case of dispute?
For qualified signature (QES), the presumption operates in favour of the party relying on it. For SES and AES, it is up to them to demonstrate reliability — hence the importance of the eIDAS evidence file provided by Certyneo.
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