You had it first. Prove the date.
An invention, a design, a manuscript, a model checkpoint, a dataset. The question in almost every dispute is not what it is, but when you had it. Hashing the work in your browser and notarizing that hash with a neutral witness gives you a signed, RFC 3161 timestampable record that this exact work existed on this date. You can prove the date without ever disclosing the work, because only the fingerprint is sent. The work itself never leaves your machine.
Seal today, reveal on your terms.
Fingerprint
Your browser computes the SHA-256 hash of the work locally. A single changed byte produces a different hash, so the fingerprint pins the exact version.
Witness
Notarize the hash with Dynamic Feed. The receipt comes back Ed25519-signed and RFC 3161 timestampable: proof this fingerprint existed at that moment, held in an append-only archive.
Reveal
Whenever you need to, disclose the work and the receipt. Anyone can re-hash the work, confirm it matches, and check the signature and timestamp against a published key. No trust in us required.
Fingerprint a work, in your browser.
Pick the file that holds your work: a PDF of the disclosure, the CAD file, the manuscript, the model weights, the dataset. Your browser computes its SHA-256 fingerprint locally with the Web Crypto API. The file is hashed in your browser and never uploaded. Nothing is stored about you.
seal record (JSON)
curl -X POST https://dynamicfeed.ai/v1/notarize -H "content-type: application/json" -H "X-API-Key: YOUR_FREE_KEY" -d '{"payload_sha256":"<your hash>","subject":"priority-<your-label>"}'
The returned receipt is Ed25519-signed and RFC 3161 timestampable. Save the receipt JSON next to the original file: together they are your priority kit. Re-verify any time against /.well-known/keys or with the MIT-licensed verifiers (see /verify and /standards). A free key is self-serve at POST /signup, details in the docs.
Later, prove the sealed work is this work.
When the day comes to rely on your priority, drop the original file and paste the receipt you saved. Your browser re-hashes the file and confirms it is byte-identical to the fingerprint the receipt sealed. This check runs entirely in your browser: neither the file nor the receipt is uploaded.
A match proves the file you hold now is exactly the bytes sealed on the receipt's date. To also confirm the receipt itself is genuine and its timestamp intact, check its signature at /verify.
A dated fingerprint is corroboration.
Defensive publication and prior art: a sealed fingerprint, revealed later, is evidence the idea was in your hands before someone else's filing date. Trade secrets: prove a secret existed in a specific form on a date without disclosing it, which matters when misappropriation is alleged. Design and authorship disputes: show your version predates the copy. Model and dataset provenance: pin exactly which weights or which data you held, when. In each case the record is corroboration that does not depend on anyone taking your word for it, because opposing parties can re-verify it themselves.
Evidence of a date, not a patent.
Dynamic Feed is a neutral witness, not a registry, examiner or adviser. A priority proof shows that this exact work existed on a date and has not changed since. It does not grant any intellectual property right: patents, designs and trademarks are granted only by the relevant offices, and it is not a substitute for filing. It does not prove who authored the work, only that these bytes existed as of the timestamp, and mailing yourself a sealed envelope was never protection either. Use it as corroborating evidence of a date of possession beside proper filings and advice from a qualified attorney. Advisory evidence, tamper-evident not tamper-proof, not a certification and not legal advice.
One call seals every version.
Wire the notary into your version control or release pipeline and every build, draft and checkpoint gets a dated, signed fingerprint automatically, hash only, self-serve to scale.