You made something. A song, a chapter, a logo, a business plan, a codebase. Sooner or later you may need to show a client, a platform, or a court that it existed before a certain date, or before someone else's copy of it did.
The good news: timing evidence is the easiest kind to get right, and you can get it for free. The catch: most of the folk methods people rely on don't hold up, and the strong methods only work if you use them before the dispute, not after.
Why "first" is worth proving
Most originality disputes are really timing disputes. A plagiarism accusation, in either direction, comes down to whose version existed first. A contested freelance deliverable comes down to what you sent and when. An idea a partner "independently developed" comes down to what you can show predates the partnership.
In each case, the person with a dated, independent, tamper-evident record starts the conversation from higher ground. Often the record ends the conversation on its own: it's hard to argue with a public entry that predates your claim.
The poor man's copyright myth
The famous folk method: seal your work in an envelope, mail it to yourself, and keep it unopened. The postmark supposedly proves the date.
The problems are well known. Envelopes can be steamed open and resealed, or mailed unsealed and filled later. The postmark dates the envelope, not what's inside it. And the U.S. Copyright Office says plainly that mailing a copy of your work to yourself is not a substitute for registration. Courts have given the practice very little weight. The email version, sending the file to yourself, inherits the same weakness: the date lives in records you or your provider control.
The instinct behind it is exactly right, though: create dated evidence that's hard to tamper with. The fix is to put the date somewhere nobody controls, including you.
What a timestamp can prove
- That this exact file, byte for byte, existed at a specific moment.
- That you (or your account) had it at that moment.
- That yours is the earliest public claim on record for those bytes.
- That the file hasn't changed since: one edited character breaks the match.
What a timestamp can't prove
- That you created the work. It proves possession at a moment, not authorship truth.
- That you hold a copyright registration. Registration is a separate legal process with its own benefits, like statutory damages in the US.
- That nobody privately had the work earlier without stamping it.
A timestamp is evidence, not a verdict, and this page is not legal advice. For a real dispute, bring your evidence to a lawyer. What a timestamp does is make sure you have evidence worth bringing.
Authorship in the AI era
AI-assisted work makes timing evidence more valuable, not less. Output is cheap to generate and nearly impossible to attribute after the fact, so "you lifted that from my AI session" is an accusation with no natural defense, unless you can show your version existed first.
Stamping the exact output ties it to your account at a specific moment. Whether AI-assisted work qualifies for copyright is unsettled law that varies by country; a timestamp doesn't decide that question. It preserves your side of the timeline while the law catches up. You can also attach an optional "Made with AI" disclosure to a stamp, useful if you publish under rules like the EU AI Act's Article 50 marking requirements.
How to build the habit
The method is simple, and it's covered step by step in how to timestamp a file for free. The habit matters more than the tool:
- Stamp when the work exists, not when the dispute does. A record made after an accusation proves nothing about before it.
- Stamp meaningful versions. The finished draft, the sent contract, the shipped design. Each stamp is a dated waypoint in your work's history.
- Keep the files. The stamp records the fingerprint; the file itself is what you'll drop at the verify page to demonstrate the match.
Identity is optional and layered. You can stamp with a bare account and the timestamp still holds. If you publish under your name, proving a handle or domain upgrades your stamps to a Verified byline, so the record says "made by a person who demonstrably controls @you," not just "made by account 4c1f."
Common questions
Does a timestamp give me copyright?
No. In most countries copyright exists automatically when you create a work; registration is a separate legal process with its own benefits. A timestamp is evidence of when you had the work, which is useful in a dispute, but it is not a registration.
Does mailing my work to myself work?
It is widely doubted. Envelopes can be unsealed and resealed, the postmark dates the envelope rather than its contents, and the U.S. Copyright Office says plainly that the practice is not a substitute for registration. A cryptographic timestamp is free and far harder to dispute.
Can I prove authorship of AI-assisted work?
A timestamp proves you had this exact output at this moment, which settles timing disputes. Whether AI-assisted work qualifies for copyright is unsettled law that varies by country; a timestamp doesn't decide that question, it preserves your evidence while it gets decided.
Do I have to reveal my work to timestamp it?
No. Only the file's SHA-256 fingerprint is recorded; the file itself never leaves your device. You can keep a manuscript, pitch, or invention private and still hold a public record that it existed, revealing the content only if a dispute ever requires it.