Online proof of prior existence: how to choose a service

Services that date a creation online look alike at first sight. They all calculate a fingerprint of the file and issue a certificate. The differences show on the day you have to produce the proof before a judge, a client or an investor. This guide gives you the criteria to compare them.

To choose between a Soleau envelope, an official report and online timestamping, first read our comparison of the three methods. This guide covers what sets one service apart from another.

Four questions to ask before choosing

How many files will you date? A one-off deposit and a creation that changes every week do not call for the same service.

Are your files confidential? A trade secret, an unpublished manuscript or source code require that the content is never made public.

Who will need to verify the proof? A judge, a client, a foreign partner. Each of them must be able to verify it without your help.

What will you do if you are copied? Proof is only the first step. You then need to be able to defend yourself.

The nine criteria

Who sets the date

The date must come from a source the provider does not control, for example a public ledger such as a blockchain, or an independent timestamping authority. A date set only by the provider's own server is easier to challenge.

Anchoring per file or in batches

Some services group the fingerprints of many files before recording them all at once. The proof for your file then relies on an intermediate calculation that has to be reconstructed. With file-by-file anchoring, each deposit has its own record, which is simpler to present.

Confidentiality of the content

Only the fingerprint should be published, never the file. Also check where and how the file is stored, if it is stored at all.

Verification by a third party

A judge or an expert must be able to verify the certificate without creating an account, and without depending on the provider.

Accepted formats

Image, text, code, audio, video, archive. A service limited to certain formats will sooner or later force you to switch.

Pricing model

Either pay per deposit, where each deposit is charged, or a subscription, which includes deposits. Paying per deposit suits occasional deposits. A subscription suits those who date every version.

Legal protection insurance

Proof does not pay for a lawsuit. Check whether insurance covers your lawyer's fees in a dispute, and look at the limit, the exclusions and the waiting period.

Legal support

If you are copied, someone should help you assess the situation and choose the right course of action.

Hosting and governing law

Hosting in Europe and a contract governed by French law make things simpler for a user based in France, in particular regarding the GDPR.

Comparison table

When the Soleau envelope or an official report remain the right choice

For a finished work deposited only once, the e-Soleau is simple and well recognised. For a high-stakes situation, or to have a copy recorded online, a report by a commissaire de justice provides very strong evidence. Timestamping does not replace this report of the copy. It proves what you had, and on which date.

Combining methods

Date your work as you go with online timestamping. The day a copy appears, have it recorded by a commissaire de justice. Your file then brings together your dated creations and the proof of the copy.

Is online timestamping valid before a judge?

In France, evidence is free in civil matters (article 1358 of the Civil Code). The judge assesses its weight, which rests on the reliability of the process and on keeping the original file. See the legal value of an Ipocamp proof.

Is a blockchain essential?

No. It ensures that the date does not depend on the provider, which an independent timestamping authority also provides.

Is price the right criterion?

It matters, but compare what it includes, meaning the number of deposits, the retention period, verification and insurance. A cheap deposit that must be renewed, with no defence in a dispute, can end up costing more.

With Ipocamp, in practice

Ipocamp records each file separately on the Tezos blockchain, publishes only the fingerprint and issues a certificate anyone can verify. The subscription includes Covéa legal protection insurance and legal support. Your first 5 deposits are free, no account needed.

This article is for informational purposes only and does not constitute legal advice. The e-Soleau information comes from the INPI website. The features of other services vary. Check the conditions in force.