You have just finished a demo or a master and you are about to send it to a label, a producer, an artist or a competition. The problem is not proving that the file sits on your computer today. It is being able to show, months later if need be, that this precise version already existed before you sent it. Sealway binds the fingerprint of your file to a qualified electronic timestamp under eIDAS.
Built for
Before it is published, a demo or a master passes through many hands.
A musician finishes a track. They send it to a label, a producer, a singer, another composer, a publisher, a client, a competition, platforms, or simply to several people for an opinion. A few months later, a very similar track appears.
At that point, remembering that you created it first is no longer enough: you have to be able to produce something that shows the file already existed on that date.
In France, no formality is needed to be protected, and the Berne Convention makes the same rule apply across its member countries. The difficulty is not having rights. It is being able to establish, on the day it matters, what existed and when.
The author of a work of the mind enjoys, by the mere fact of its creation, an exclusive intangible property right in it, enforceable against all. The French Ministry of Culture sums it up: protection is acquired without the author having to complete any administrative formality of filing or prior registration. The Berne Convention says the same for its member countries: the enjoyment and the exercise of these rights “shall not be subject to any formality” (art. 5(2)).
The work is deemed created, regardless of any public disclosure, by the mere realisation, even unfinished, of the author’s conception. A demo, a rough mix or a sketch already falls under copyright, provided it is original.
Authorship belongs, unless proven otherwise, to the person or persons under whose name the work is disclosed. That presumption is rebuttable: it can be challenged by any means. No service, Sealway included, confers authorship.
The right exists from creation. But if a dispute arises, you need material documenting the existence of the work, its content, a date, its creative process, its versions and the exchanges with third parties. The French Ministry of Culture notes that a filing or a registration may make it easier to prove authorship and the date of creation. That proof is what Sealway contributes to, and that alone.
French Ministry of Culture · technical sheets on copyright
The sheet recalls that protection requires no formality, then lists the ways of dating a creation: a commissaire de justice or a notary, a Soleau envelope with the INPI, a collecting society, and sending the work to oneself in a sealed envelope.
Nevertheless, the existence of a filing or a registration, particularly in the context of litigation, may make it easier to prove the authorship and the date of creation of the work.
What Sealway takes from it
The right is not filed. The date, however, is proven.
Every musician knows the method. It is not worthless. It is old, cumbersome, and designed for a world of physical media.
The French Ministry of Culture’s sheet still mentions it: the author may send the work “to themselves or to a third party in a sealed envelope with acknowledgement of receipt, without opening the envelope on receipt, the postmark serving as proof” (our translation). The FAQ of MusicStart, the service of the Sacem’s subsidiary, ranks it among the “more traditional” ways of obtaining proof of prior existence.
A sign of the times: since 1 April 2024, the INPI no longer accepts paper Soleau envelopes. Filing is done online, on the digital fingerprints of the files.
When the proof is created, the fingerprint of the file is bound to a qualified electronic timestamp, issued by a qualified trust service provider within the meaning of the eIDAS Regulation. It is not a date Sealway writes in a database.
A musical creation is almost never a single file. A Sealway proof can gather up to 10 files, 250 MB in total, around one work.
Each file keeps its own SHA-512 fingerprint; the whole is sealed by a single timestamp. The evidence file states which file matches which fingerprint, and each can be verified separately.
Any file type is accepted: WAV, AIFF, FLAC, MP3, AAC, MIDI, PDF, images, exported projects, archives. The proof bears on the bytes of the file, whatever its format.
A musical work does not always appear in one go. Sealway makes it possible to document the important stages of its creation.
Structure, main melody, provisional lyrics. Proof no. 1.
The chorus changes. Proof no. 2, on the new version.
Vocals and instruments recorded. Proof no. 3.
WAV master and MP3 version in one proof. Proof no. 4.
The version sent is the one of proof no. 4. The evidence file is kept before sending.
Each proof carries its own date. End to end, they document a chronology: what existed, in what form, at what moment. That is particularly useful for collaborations, co-writing, remote productions, stem exchanges, ghost production, commissioned music, advertising music, soundtracks or the successive transformations of a sample.
Creating a proof for each version is not an obligation. The stages that matter are those where a file leaves your computer, and those where the work changes significantly.
A proof created after sending says nothing about what existed before. It is created beforehand, in a few minutes.
The one you are actually going to send: the master, the demo, the stems.
Master, MP3, stems, lyrics: everything that documents this version, in one proof.
The fingerprint of each file is computed, then timestamped by a qualified provider.
Download the evidence file, or let Sealway keep your original files with a storage subscription. Either way, never modify the originals: they are what the fingerprint lets you verify.
The demo, the master or the stems go out with, on your side, dated proof of what you sent.
Co-writing, remote productions, stem exchanges: files travel in both directions.
Two artists work remotely. The first sends instrumental-v4.wav. The second adds vocals-v2.wav. A final version is then produced from both.
Months later, a discussion arises: who created what, which version existed when, when a given element was added.
Sealway does not settle the ownership of the rights or the split between co-authors: that is a matter for the agreement between the parties and, failing that, for the court. What proofs created along the way, by each participant, do provide is objective material on the chronology of the files: what instrumental-v4.wav contained, on what date, and what was added afterwards.
The simplest way: each participant creates a proof of their contribution before sending it, then a joint proof is created on the final version.
instrumental-v1.wav is finished. The beatmaker creates a Sealway proof: SHA-512 fingerprint, qualified timestamp.
They send the track to several artists, with a collaboration in mind.
A track built on a very similar composition is released.
What the beatmaker holds is an evidence file showing that a file exactly matching their instrumental already existed on 10 January. Their lawyer can use it with the other material: working files, exchanges, emails, contracts, project histories.
These means do not exclude one another. They differ in mechanism, cost and place in a creative process. The first three are French options; prices as published on the services’ websites on 20 September 2026.
| Means | Principle | Files | Indicative cost | Points to watch |
|---|---|---|---|---|
| Registered post to yourself | Sealed envelope, the postmark serving as proof; content recorded later if needed. | One physical medium per mailing. | Postage for each mailing. | Physical storage; ill-suited to successive versions; heavy handling in a dispute. |
| e-Soleau (INPI) | Online filing; receipt signed by the INPI’s server seal, with date, UTC time and fingerprint of each document; kept by the INPI. | 1 to 100 files, 2 GB in total when kept by the INPI; no size limit in fingerprints-only mode. | €15 up to 50 MB, then €10 per 50 MB, per 5-year period. | Institutional solution; kept for 5 to 20 years; confers no intellectual property right. |
| MusicStart (URights, a Sacem subsidiary) | Certificate of priority (MusicStart’s « certificat d’antériorité ») whose fingerprint is anchored on the Tezos blockchain, according to its documentation. | One file per single filing, several per work and unlimited filings with a subscription; 20 MB per file; MP3, MPEG, OGG and documents. | Free for Sacem members; otherwise €3.99 incl. VAT per single filing, or unlimited filings at €4.99 incl. VAT per month or €49.99 incl. VAT per year; one filing free for 30 days after signing up. | Designed for music; fingerprint anchored on a blockchain, with no qualified timestamp mentioned. |
| Bailiff’s report (constat de commissaire de justice) | Personal findings of a public and ministerial officer. | According to the mission given. | On quotation. | Specific evidential regime; relevant when an authorised third party must record facts in person. |
| Sealway | SHA-512 fingerprint of each file, qualified electronic timestamp under eIDAS, multi-blockchain anchoring in addition, exportable evidence file verifiable without Sealway. | Up to 10 files and 250 MB per proof, any format. | €1.99 per proof, less in a pack. | Digital and immediate; one proof per version that matters; does not establish authorship. |
Sealway is not a universal substitute for these means. A commissaire de justice’s report remains relevant when the situation requires an authorised third party to record facts in person. The e-Soleau is a recognised institutional solution. Sealway stands out by its mechanism, the qualified electronic timestamp and independent verification, and by its place in a digital workflow where versions follow one another.
The court freely assesses the material submitted to it. A Sealway proof is one item of that material: the one that establishes the existence and the integrity of a file on a given date.
File creation date, modification date, date in the file name, file-system timestamp, date shown in a piece of software, ID3 or EXIF metadata: this information depends on the computing environment and can generally be modified.
A metadata field may be one item among others, but it does not enjoy the presumption a qualified electronic timestamp derives from the eIDAS Regulation. With Sealway, the date does not come from a property of the file: it comes from an independent timestamp, bound to the file’s fingerprint.
A date that rests on a file’s metadata alone can be set aside by a court: the French Conseil d’État accepted it for site photographs (CE, 10 March 2025, no. 472387). Read our analysis of that decision →
What Sealway does for your music, and what it does not claim to do.
Texts, official documents and services cited on this page. The French sources are in French.
Sealway does not provide legal advice. These references are given for information; the evidential weight of the material produced is for the court to assess.
Source code to date before a delivery, a deliverable handed over by email: a version fixed before it leaves your hands.
One proof per version that matters: SHA-512 fingerprint, qualified electronic timestamp under eIDAS, evidence file verifiable by a third party. Join the waitlist to be notified at launch.
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