PAdES

ETSI's advanced signature format dedicated to PDF, embedded in the document.

Definition

PAdES embeds a CMS/CAdES signature inside the PDF's native signature structure (the /Sig object), so the document stays a valid, openable, visually verifiable PDF. It supports timestamping and the baseline levels B-B, B-T, B-LT, B-LTA, including LTV (Long-Term Validation), which embeds certificates and revocation data for durable verification.

Origin

Standardised by ETSI EN 319 142-1 (Electronic Signatures and Infrastructures; PAdES digital signatures), published by ETSI ESI; the underlying PDF signature mechanism is defined by ISO 32000 (PDF). Formerly TS 102 778.

Example in context

A PAdES B-LTA-signed PDF/A invoice: the /Sig dictionary holds a CMS SignedData, an RFC 3161 timestamp, plus a DSS (Document Security Store) and an archive timestamp for long-term retention.

Related terms

• ISO 32000-2 PDF 2.0 — the PDF format that carries the signature.
• CAdES — the CMS foundation of PAdES.