How do I know if a digital signature is truly valid?

Open the document and click on the digital signature. Look for the 'Signature Properties' or 'Validate Signature' option. Acrobat will show if the signature is valid based on its certificate and trust settings. You may need to update your trusted identities for full validation.

If my digital signature shows a warning, what are the first steps I should take?

Review the specific warning message to understand the issue. Check the signer's certificate details to see who signed and if it's expired. Update your list of trusted identities in Acrobat. If possible, contact the signer to confirm the signature's intent.

How is verifying a digital signature different from just seeing a scanned image of a signature?

Feature Scanned Image of Signature Verified Digital Signature. Authenticity Proof Only visual, can be easily copied or faked. Cryptographically linked to the signer's identity and certificate. Tamper Detection No way to know if document changed after signing. Automatically detects any changes to the document after it was signed. Legal Weight Often requires additional proof (witnesses, notary). Provides strong legal evidence of signer identity and document integrity. Verification Process Manual inspection, often subjective. Automated check by software against trusted certificates.

Run Audit Trail in Adobe Acrobat — How-to & AI prompts

AI prompts

2 ways to ask · copy any one

AExecute — “help me do it”Run an audit trail for the court's recent e-signature batch for [month=January]: produce a log…+

Run an audit trail for the court's recent e-signature batch for [month=January]: produce a log showing who viewed and signed each agreement and export the log to the compliance folder.

when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed.

BImprove — “do it better”Generate the [month=January] e-signature audit: include timestamps for view, sign, and…+

Generate the [month=January] e-signature audit: include timestamps for view, sign, and delegation events; attach the signed PDFs; highlight any out-of-office delegations; and prepare a one-page summary for the compliance officer identifying anomalies.

when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed.

How to do it

the tool · the steps · what to avoid

1
Open the PDF document containing the digital signature you want to validate.
2
Locate the signature field or signature panel in the document.
3
Click directly on the digital signature or open the signature panel and select the signature you wish to validate.
4
In the signature details popup, click Signature Properties.
5
In the Signature Properties dialog, click Show Certificate to review certificate details if needed.
6
Close the certificate window, then click Validate Signature in the Signature Properties dialog.
Best practiceIf the signature status shows as 'Unknown' or 'Not Valid', check if the signer's certificate needs to be added to your list of trusted identities.
7
Review the validation result displayed in the Signature Properties dialog.

In the appWith the API

You can view detailed information about the signature's validity and certificate by clicking on the signature and opening Signature Properties.

This runs in the Acrobat app - there is no separate API for this task.

Glossary

words on this page

Digital SignatureAn electronic mark on a document that proves who signed it and that the document has not changed.ExampleA digital signature on your tax return confirms you submitted it and that its contents are unchanged.

CertificateAn electronic file that proves a person's or organization's identity online, like a digital ID card.ExampleYour certificate confirms your identity when you access secure online government services.

Trust RelationshipWhen your computer or software believes a digital certificate is real and safe to use.ExampleYour browser forms a trust relationship with a secure website to protect your online banking session.

Who does this

3 roles

Contract ManagerLegal AssistantCompliance Officer

FAQ

about this task

Open the document and click on the digital signature.
Look for the 'Signature Properties' or 'Validate Signature' option.
Acrobat will show if the signature is valid based on its certificate and trust settings.
You may need to update your trusted identities for full validation.

A trust relationship is important because it tells your computer or software that the certificate used to sign the document comes from a reliable source. If you don't trust the source of the certificate, you cannot be sure the signature is authentic or that the document has not been tampered with. It's like trusting a known ID card versus one from an unknown person.

Long-Term Validation (LTV) means adding extra information to a digital signature so it remains valid long after it was created, even if the signer's certificate expires or is revoked. This is important for documents that need to be legally valid for many years, like contracts or deeds. Without LTV, older signatures might become invalid over time, making it harder to prove their authenticity later.

Review the specific warning message to understand the issue.
Check the signer's certificate details to see who signed and if it's expired.
Update your list of trusted identities in Acrobat.
If possible, contact the signer to confirm the signature's intent.

Feature	Scanned Image of Signature	Verified Digital Signature
Authenticity Proof	Only visual, can be easily copied or faked.	Cryptographically linked to the signer's identity and certificate.
Tamper Detection	No way to know if document changed after signing.	Automatically detects any changes to the document after it was signed.
Legal Weight	Often requires additional proof (witnesses, notary).	Provides strong legal evidence of signer identity and document integrity.
Verification Process	Manual inspection, often subjective.	Automated check by software against trusted certificates.

Run Audit Trail

When to use it

AI prompts

How to do it

Glossary

The real tasks

Who does this

FAQ

Sources

Adobe help