# PDF Signature Verification and File Integrity Evidence

Preserve the original PDF hash, compare it with a trusted reference checksum, verify embedded signatures, and record certificate-chain findings without treating tool output as legal validity or proof of signer identity.

> Canonical page: https://elysiatools.com/en/hubs/pdf-signature-verification-workflows

- **Keywords:** PDF signature verification, PDF file integrity, certificate chain review, checksum evidence, signed document audit, trust boundary

## Frequently asked questions

### Does a matching checksum prove who signed or published the PDF?

No. It shows byte agreement with the supplied reference. The reference source, certificate trust, signer identity, and legal significance require separate review.

### What should I preserve before verifying a signature?

Keep an unchanged evidence copy and record its source, filename, version, acquisition context, calculated digest, expected checksum, and the verification settings. Do not repair or resave that copy first.

### What if the signature verifies but the certificate is expired or untrusted?

Record the successful cryptographic check together with the expiry or trust problem, then apply the organization's policy. Do not convert a partial result into automatic acceptance.

### Is a positive tool result proof of legal validity or signer identity?

No. These tools provide technical evidence about bytes, signatures, and available certificate details. They do not automatically establish legal validity, authority to sign, or the real-world identity of the signer.

## Related content

- [PDF Archival, Accessibility, and Trust Review](https://elysiatools.com/en/hubs/pdf-archival-accessibility-trust): Clean scanned pages, add OCR, prepare PDF/A files, inspect accessibility structure, add bookmarks, and verify signatures before archival handoff.
- [Detached Signature and File Integrity Verification](https://elysiatools.com/en/hubs/detached-signature-and-file-integrity-verification): Generate or reproduce a file hash, compare it with a published checksum, and verify a detached Ed25519 signature with a separately trusted public key.