Auditors flagged several change advisories as lacking tamper evidence across the last two reviews. Identify the recurr…
Open the PDF document containing the digital signature you want to validate.
If prompted, enable all necessary trust settings for the certificate authority used by the signature.
CautionIf the certificate is not trusted, Acrobat may not be able to validate the signature correctly.
Look for the Signatures panel on the right side, or click on the signature field in the document to open the signature details.
In the Signatures panel or details dialog, review the signature status message to check if the signature is still valid after document changes.
NoteAcrobat will indicate if the document was modified after signing and whether the changes are permitted (such as filling in forms or adding approved annotations) or if the signature was invalidated by unauthorized edits.
Expand the signature properties to view the list of changes made after signing, if any.
Best practiceClicking 'View Signed Version' lets you compare the signed state to the current version to see exactly what changed.
Confirm whether the signature remains valid or has been invalidated by edits, as indicated by Acrobat.
You can quickly check if a signature is still valid after changes by opening the signature panel and reviewing the status message.
This runs in the Acrobat app - there is no separate API for this task.
When a certificate is 'trusted', it means your Adobe Acrobat software recognizes the signer's identity as authentic. This trust is based on a relationship you or your organization has set up, often with a Certificate Authority. Trusting a certificate helps ensure the document's origin and integrity.
If an advisory is 'Unsigned', it means it lacks a digital signature to verify its origin or that it hasn't been altered. While the content might still be correct, you cannot digitally confirm its authenticity or integrity. You should verify the source through other means, like checking the official website or contacting the sender directly, before fully trusting the information.
Adding verification information, like a timestamp, makes signatures 'self-validating' over time. This is called Long-Term Validation (LTV). It means the signature can still be proven valid even if the signer's certificate later expires or is revoked. This protects the document's integrity for many years.
| Action | Purpose | Focus |
|---|---|---|
| Verifying a Signature | Checks if a specific signature on a document is valid, authentic, and unchanged. | The individual signature and document integrity. |
| Managing Trusted Identities | Sets up which signers or Certificate Authorities your software will automatically trust in the future. | The overall trust settings and relationships for all signatures. |