Minute Notary
Two ways to check
Online with the code, or offline with the file
Look up the code printed on the document
The check confirms the Minute Notary seal, the trusted timestamp and the tamper-evident record. It never shows what the document says.
Where is the code? In the small grey line at the top of every page of the sealed PDF: “Verify: minutenotary.ca/verify · Code: …”. The QR code on the seal opens the same check.
Verify the file itself, without uploading it
Drop the sealed PDF and its proof file (.proof.json) into the open-source verifier. It runs entirely in your browser; nothing leaves your computer.
No proof file? Ask Minute Notary for the evidence package of your document. It holds the PDF, the proof, the public key and the timestamp token.
What gets checked
Five checks, in plain words
The offline verifier runs all five and gives one verdict.
- 01
The file is unchanged
hashThe fingerprint (SHA-256) of the exact PDF you hold equals the one recorded when it was sealed. Change one byte and this fails.
- 02
The seal belongs to that file
signatureAn ECDSA P-256 signature over that fingerprint checks out with the public key in the proof.
- 03
The key is the issuer's key
keyCompare the key fingerprint the verifier prints with the one Minute Notary gives you, or give the verifier a trust list.
- 04
The time is independent
timestampAn RFC 3161 timestamp from an outside authority proves when the seal was made, not just what the server clock said.
- 05
The seal is on the record
ledgerThe seal's entry in an append-only, hash-chained ledger recomputes from the proof, so it cannot be slipped in later.
For developers and courts
The verifier is open source
Library, command line and browser page under the MIT licence, with the seal format documented so anyone can write their own checker.
# check a sealed PDF next to its proof file (Node 20+, no install) $ npx sealed-pdf-verify document.pdf --proof document.proof.json # or a whole evidence package $ npx sealed-pdf-verify evidence.zip
- Documentation
- sealed-pdf-verify.readthedocs.io
- Browser page
- minutenotary.github.io/sealed-pdf-verify