Soleau envelope

The enveloppe Soleau is a service offered by the INPI which makes it possible to give a certain date to a creation, an idea, an invention or a document, by depositing it in sealed form or, today, electronically. It takes its name from its inventor, Eugène Soleau. The enveloppe Soleau confers no intellectual property right. It is a means of proving the anteriority of a creation at a given date.

How the enveloppe Soleau works

First, the depositor describes the creation in a document, in text, drawings or photographs, in any form but within a limited size. Second, the deposit is registered and dated by the INPI, which keeps one copy and returns the other to the depositor, or archives the electronic file with a digital fingerprint. Third, storage lasts five years, renewable once, ten years in all. The content remains secret: the INPI does not read it and does not publish it. The details are set out on the website of the INPI.

Evidentiary value and limits

The enveloppe Soleau proves that a person was in possession of a given content at a given date. It is useful for establishing the date of creation of a work protected by copyright, for supporting a prior user right against a third party’s patent, or for documenting know-how in the context of trade secrets. It does not however protect the invention: only a patent confers an exclusive right. Nor does it prove authorship or inventorship, but only possession of the content. Other dating methods exist, such as a bailiff’s report, a deposit with a notary or qualified electronic time-stamping.

Key points

In practice, the enveloppe Soleau is a simple and inexpensive evidence-building tool, suited to the preliminary phases of a project, before the filing of a patent or a design. It should never be regarded as a substitute for filing a title. The firm advises on organising the proof of creations and inventions, notably in the context of trade secrets, as presented on the page trade secrets attorney.