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

Click on the digital signature within the PDF. A Signature Panel will appear, showing its validity status. A green checkmark usually means it's valid, but always check the details for certificate trust. If there are warnings, you may need to update your trusted identities.

If my document's digital signature shows a warning, what should I do?

First, check the specific warning message in the Signature Panel. It might mean the signer's certificate is not in your trusted list; you can add it. It could also mean the document was changed after signing, which makes the signature invalid. Contact the signer to understand the issue if you are unsure.

What is the difference between 'validating' a digital signature and 'verifying certificate information'?

Action What it checks Why it matters. Validating a Signature Checks if the signature is authentic, if the document changed, and if the signer's certificate is trusted. Confirms the entire signature's integrity and who signed the document. Verifying Certificate Information Looks at the details of a specific certificate, like its owner, issuer, and expiration date. Helps you decide if you want to trust the source of a signature or encryption.

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

AI prompts

2 ways to ask · copy any one

AExecute — “help me do it”Audit the team's signed agreements trail: export the agreement history, verify every approval…+

Audit the team's signed agreements trail: export the agreement history, verify every approval has a timestamp and signer identity, and deliver a gap report highlighting missing or unsigned items by [deadline=Friday].

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

BImprove — “do it better”Make the agreement trail audit actionable: produce a sortable list of agreements with signer,…+

Make the agreement trail audit actionable: produce a sortable list of agreements with signer, timestamp, and IP if available; flag any signatures missing timestamps or with inconsistent signer identities, and recommend remediation steps for each gap.

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.

TimestampA timestamp proves exactly when a document was signed.ExampleThe timestamp on the digital signature shows the agreement was finalized at 2:15 PM.

Who does this

3 roles

Contract ManagerLegal AssistantCompliance Officer

FAQ

about this task

Click on the digital signature within the PDF.
A Signature Panel will appear, showing its validity status.
A green checkmark usually means it's valid, but always check the details for certificate trust.
If there are warnings, you may need to update your trusted identities.

A 'trusted identity' is a certificate from a person or organization that you have told Acrobat you trust. It matters because Acrobat uses this trust to decide if a digital signature is real and from whom it claims to be. If you don't trust the identity, Acrobat cannot fully confirm the signature's authenticity, even if it looks correct. Managing trusted identities helps you control who you accept signatures from.

First, check the specific warning message in the Signature Panel.
It might mean the signer's certificate is not in your trusted list; you can add it.
It could also mean the document was changed after signing, which makes the signature invalid.
Contact the signer to understand the issue if you are unsure.

Adding Long-Term Validation (LTV) information to a digital signature makes it self-validating over time. This is important because the certificates used for signing can expire or be revoked. LTV embeds all the necessary information, like timestamps and certificate status, directly into the PDF. This means you can verify the signature's validity years later, even if the original certificate or timestamp server is no longer available, ensuring the signature's integrity for the long term.

Action	What it checks	Why it matters
Validating a Signature	Checks if the signature is authentic, if the document changed, and if the signer's certificate is trusted.	Confirms the entire signature's integrity and who signed the document.
Verifying Certificate Information	Looks at the details of a specific certificate, like its owner, issuer, and expiration date.	Helps you decide if you want to trust the source of a signature or encryption.

Audit Signature Trail

When to use it

AI prompts

How to do it

Glossary

The real tasks

Who does this

FAQ

Sources

Adobe help