Glossary
What Is a PAdES Seal?
PAdES is the European technical standard behind most native e-signature tools, including Braigest's. It defines how an advanced electronic signature is embedded directly inside a PDF, so the document itself carries proof of who signed it and whether anything changed afterward. This guide explains what sealed and intact actually mean in practice.
- PAdES: the ETSI standard for signatures embedded in a PDF
- Sealed means the signature and the document are one file
- Intact means nothing has changed since the moment of signing
What does PAdES actually stand for
PAdES stands for PDF Advanced Electronic Signature. It is a European technical standard, published by ETSI as EN 319 142, that defines how an advanced electronic signature is embedded directly inside a PDF file. Rather than attaching a separate certificate or pasting in an image of a handwritten signature, PAdES writes the signature data into the PDF's own structure. That is what lets any standard PDF reader check the signature later, without needing a separate tool from whoever built the signing product in the first place. It is the format most native, in-app e-signature tools use, including the one built into Braigest's onboarding flow.
What does it mean for a document to be sealed
Sealing means the signature and a cryptographic fingerprint of the document's exact content, at the moment of signing, are written into the PDF itself. The seal is not a stamp glued on top of the file. It is part of the file's own data, generated from the file's content, so it can only match a document that has not changed since the signature was applied. Any later edit, even a single character, changes the fingerprint and breaks the match between the seal and the document. That is the property that makes a sealed PDF different from a scanned signature pasted into a page, which proves nothing about what happened to the document afterward.
How can I tell if a seal is still intact
Open the PDF in any reader that supports digital signature validation, which includes free, widely used software, not a special tool from the vendor who sealed it. The reader recalculates the document's fingerprint and compares it against what was recorded at signing. If nothing has changed, it reports the signature as valid and the document as intact, usually with a visible panel showing the signer, the time and the certificate used. If even a small change was made after signing, the same panel reports the signature as invalid or the document as modified. You do not need to trust a claim on a page. The reader tells you directly whether the seal still matches.
Is a seal the same thing as a signature
Not quite, though PAdES carries both in the same file. A signature is the act of a specific person consenting to sign, which is why an advanced electronic signature is tied to that person's identity and intent. The seal is the technical mechanism, the cryptographic fingerprint written into the PDF, that fixes the document at the moment of signing and lets anyone check later whether it changed. In everyday use, people say a document is sealed and signed almost interchangeably, and for a client onboarding pack that is a reasonable shorthand: one action by the client both records their consent and locks the finished document.
Why it matters when onboarding a client
A client onboarding pack is often more than one document: an engagement letter, a data-processing addendum, a consent form. Signing each one separately, in a separate tool, means keeping several signature records straight and explaining to an auditor which one covers which page. A native PAdES seal changes that. The client signs once, at the end of the flow, and that single signature seals every document generated for their case, because all of them came from the same intake. Anyone who later needs to confirm a document has not been altered opens it in a normal PDF reader and checks the seal, without asking your firm for a separate certificate or an export from a signing vendor.
In Braigest
Every signature in Braigest applies a native PAdES seal
Signing is a step inside the onboarding flow itself, not a separate product. One signature seals the whole document pack with a PAdES seal and an evidence page, on every plan starting at Solo, €29 a month.
Frequently asked questions
Is a PAdES seal legally valid in the EU?
Yes. PAdES is one of the signature formats recognised under the eIDAS Regulation (EU) 910/2014, which gives an electronic signature legal effect and admissibility as evidence across member states, whether or not it reaches the top qualified tier.
Do I need special software to check a sealed PDF?
No. Any PDF reader that supports digital signature validation, including free, widely available software, can check a PAdES seal. You do not need the tool that created the seal in the first place.
What happens if someone edits a sealed document?
The seal breaks. Reopening the file in a compliant reader shows the signature as invalid or the document as modified, because the recalculated fingerprint no longer matches what was recorded at signing.
Is a PAdES seal the same as a qualified electronic signature?
Not necessarily. PAdES is a file format, used for advanced and qualified signatures alike. Braigest applies an advanced electronic signature with a PAdES seal, not a qualified one, which is enough for most private-law onboarding documents.
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