When a document is disputed, the other side's lawyer does not start with the law. They start with a short list of plain questions about the file in front of them. Most of them can be answered in a sentence if you prepared, and most of them cannot be answered at all by an ordinary PDF. Here are the ten that come up most, what evidence answers each one, and where a plain file falls short.
1. Who made it?
An ordinary PDF carries an author field, and anyone can type anything into it. A timestamp does not fix this on its own, because it shows when a file existed, not who wrote it. Authorship needs a second piece of evidence: a signature from an identifiable person, or an identity check on the account that sealed the file.
2. When was it made?
The creation date inside a plain PDF is written by whatever computer produced it, and a clock can be set to any day. A sealed document carries a trusted timestamp under RFC 3161, issued by a third party rather than by you. Under Article 41(2) of the eIDAS Regulation, a qualified electronic time stamp enjoys the presumption of the accuracy of the date and time it indicates.
3. Has it changed since?
Sealing records a cryptographic fingerprint of the document at that moment. The how it works page describes it as proof that even a minor alteration would be detectable. A plain PDF has no fingerprint on record, so the only comparison anyone can make is your copy against theirs.
4. Who signed it?
A picture of a handwritten signature pasted into a PDF proves nothing about who placed it there. A cryptographic signature is tied to a certificate. The validator on swisstrustlayer.com shows who signed the document, when, and with which certificate.
5. What level of signature is it?
This is where lawyers get specific. Under Article 25 of eIDAS, an electronic signature cannot be denied legal effect solely because it is electronic, and a qualified electronic signature has the equivalent legal effect of a handwritten one. In Switzerland, Article 14 paragraph 2bis of the Code of Obligations equates a qualified electronic signature combined with a qualified time stamp, under the Federal Act on Electronic Signatures (ZertES), with a handwritten signature, unless a statute or the contract says otherwise. The validator recognizes qualified signatures under both frameworks.
6. Was the signer identified?
The signature shows which certificate was used. Who the certificate holder really is depends on the identity check behind it. A plain PDF has no such check at all. If identity matters in your dispute, keep the record of how the person was verified alongside the file.
7. Can I verify it myself, without your help?
With a sealed document, yes. Each one comes with a public verification link that works without creating an account, and the validator takes an uploaded signed PDF with no registration or login. It checks the signature chain, the issuing certificate authority, certificate expiry and timestamp integrity. Only signature metadata is processed, and the document content is not stored.
8. What does the timestamp actually prove?
That the exact file, as it was at that moment, existed then and has not been altered since. That is all, and it is a lot. It does not say who wrote the file, whether its contents are true, or whether the person who sealed it owns the rights to it. The presumption in Article 41 covers the date, the time and the integrity of the data, nothing wider. Say so plainly, because the other side will.
9. What happens if the file was edited?
An edited copy has a different fingerprint, so the validator reports that the content was modified after signing. The original sealed file still verifies as it was. This is why a sealed original is worth more than a folder of later versions: you can show which one is the fixed point and which ones came after.
10. Where is the original kept?
The seal covers a fingerprint of your document, so the exact original file has to be kept by you. If the file is lost, the fingerprint cannot rebuild it. Store the sealed file itself in more than one place, together with its certificate, which has its status archived at the time of sealing so that it can be checked years later.
Close the gaps before a dispute
Go through the list with one important file in mind, maybe a contract, a design, or a manuscript. The questions a plain PDF cannot answer are the ones to close before a dispute, because a timestamp cannot be added backwards. You can seal a document and hand out the public verification link the same day.
Seal your first document on Swiss Trust Layer or read the full mechanism on how it works.
