What is timestamped proof of prior existence?

A timestamped proof of prior existence shows that a file existed, in a precise state, on a precise date. Ipocamp computes your file's cryptographic fingerprint (a unique string of characters derived from its content), then timestamps it by recording it in an unalterable public registry, whose network sets the date independently of Ipocamp (see the glossary).

Why it matters

In France, copyright arises from the act of creation itself, with no registration required. But in a dispute, you need to be able to show that you had the creation before the other party. That is the whole point of a proof of prior existence: dating your work before you show it, publish it or hand it over to someone else.

What the certificate contains

The certificate links three elements: the file's fingerprint, the timestamp date and the author you chose for the deposit. It is this combination that constitutes the proof.

The fingerprint is a 32-byte sequence computed from the file's content (a SHA-256 hash). It is unique to that file and can in no way be used to rebuild its content. If a single byte of the file changes, the fingerprint changes entirely.

What it proves, and what it does not

It proves that this file, in this exact state, existed no later than the date shown.

On its own, it does not prove that you are the author: it dates a file deposited under your name. Other evidence, such as drafts, successive versions or exchanges, strengthens the case.

It does not create an industrial property right: for a monopoly on an invention or a trademark, a patent or trademark filing is still required.

Keep the original file

To rely on the proof, you must be able to produce the original, unchanged file: it is what allows the fingerprint to be recomputed and compared with the certificate. Keep it exactly as it is, or use the encrypted storage offered with your account.

To go further

The technical mechanics are explained on the Technology page. For the weight of the proof before a court, see The legal value of an Ipocamp proof and Building a solid evidence file.

This article is for general information only and does not replace advice from a legal professional.