Signing time confirmed by an independent authority
The time on a sign.yt signature does not come from our server clock alone. A timestamping authority signs it too, so the date holds up when someone asks.
Four authorities, one signature
sign.yt asks Certum for the timestamp first. If it does not answer, the next authority in the list takes over: DigiCert, then Sectigo, then FreeTSA. One signature always uses one authority from start to finish, and a recovered primary is used again after a few minutes.
If every authority is unreachable, the document is still signed at the PAdES-B-B level instead of waiting forever.
Long-term validation built in
With a timestamp in place, the final seal is extended with validation data and a document timestamp (PAdES-B-LTA). The roots of all four authorities ship with the platform, so the validation path can be built without extra setup.
That means the signature can still be checked years from now, after the signing certificates have expired.
Frequently asked questions
What is an RFC 3161 timestamp?
A small token signed by a timestamping authority that proves a given hash existed at a given time. It is embedded in the PDF signature.
What happens if a timestamping authority is down?
sign.yt moves on to the next one in the list. Only if all of them fail is the signature created without a timestamp.
Can I use my own timestamping authority?
The authority list is set per platform. Contact us if your contracts require a specific qualified provider.
More features
- Public verification
Each signed document carries a QR code and short link to a public check page. Masked names, signing dates, seal status and a file comparison.
- Profil Zaufany and qualified signatures
Let Polish signers use Profil Zaufany, e-dowód or mObywatel via Węzeł Podpisu, or sign with a qualified electronic signature from a trust service provider.
- Audit trail
Every action is logged in an append-only, hash-chained audit log. Signatures are chained per document and a certificate of completion is added to each PDF.