What is an electronic signature? Complete 2026 guide

An electronic signature is a set of data in electronic form that is attached to, or logically associated with, other electronic data and that the signer uses to sign. This definition, set out in the eIDAS regulation (Regulation (EU) 910/2014), covers a wide spectrum of technical mechanisms, from the simplest (ticking a box, typing a name) to the most sophisticated (qualified cryptographic certificate).

Under French law, Article 1367 of the Civil Code provides that “the signature required for an act to be validly executed identifies the person who affixes it” and that, when electronic, it “consists in the use of a reliable identification process guaranteeing its link with the act to which it relates”. The reliability of the process is presumed for qualified signatures within the meaning of eIDAS.

In practice, an electronic signature performs three functions: it identifies the signer, it expresses their consent to the content of the document, and it guarantees the integrity of the document (any subsequent modification is detectable).

Mechanism-i kakki tukik: l'authentication signataire-mit tamarmi l'integrity document-mit.

To authenticate the signer, one or more identification factors are used: a trusted email address (single-use link), an OTP code received by SMS, a personal cryptographic certificate, and so on. To guarantee integrity, a fingerprint (hash) of the document is calculated at the moment of signing. If the document is altered afterwards, the fingerprint no longer matches — and the signature is invalidated.

In solutions such as Certyneo, the process relies on PDF processing libraries that embed this cryptographic metadata directly into the file. A timestamped audit trail (action log) completes the set-up by recording every step: sending, opening, OTP validation, signing, and so on.

From a technical perspective, several security mechanisms strengthen the inviolability of the process: qualified timestamping (RFC 3161) appends certified time proof to each signature; TLS 1.3 encryption protects data in transit; the signer's geolocation and IP address are recorded for traceability; finally, in certain flows (AES/QES), behavioral biometric data (typing speed, pressure) complement the identity fingerprint.

The concept of non-repudiation is central: thanks to the timestamped and cryptographically signed audit trail, it is technically impossible for a signer to deny signing a document without falsifying the chain of evidence. Regarding archiving, French regulations (decree 2016-1673) impose 10-year retention for most commercial documents — Certyneo ensures this archiving with evidentiary value in sovereign hosting (EU).

Franssummiut, sapallianik sifrirsuq qanuq loi n°2000-230 13 marsimmi 2000 pissuk, Code civil iluani iluarianngituk sifrirsuq immik sapallianik immik inuit agulinniraa papinnirmiuq. Article 1366-imiut sapallianik sifrirsuq « inuit agulinniraa papinnirmiuq pisuk ».

Eurruppaamiuq qanuqumik, naatiraliuraa eIDAS (UE) n°910/2014 qanuniq atausivik sapallianik sifrirsuq pisuk. Article 25-imiut pisuk: « sapallianik sifrirsuq qanuniq inuuguq naamik atausiviq sifrirsuq atausivik pissuk ». Sapallianik qanuq (QES) aglaksimagut qilak pissuq qallunaat sapallianirmik 27 nutaat.

Dokumantin atausivik (innuguruq sapallianik, innuguruq iluarianngituk, sapallianirmik, NDA, mallunitsiarniq), sapallianik aglaksimajuk (AES) inuuguq agulinniraa immik pisuk. sapallianik qanuq (QES) atausivik atausiviq dokumantin inuit sapallianirmiuq qanuniq pissuk.