How do I add a trusted timestamp to my PDF document?

Open your PDF in Acrobat. Go to 'All tools' > 'Use a certificate'. Select 'Timestamp' to add a time from a trusted source. After signing, right-click the signature and choose 'Add Verification Information' to include LTV data.

What is the difference between a simple digital signature and one with a trusted timestamp and LTV?

Feature Simple Digital Signature Signature with Trusted Timestamp and LTV. Validity over time May become invalid when certificate expires. Stays valid long-term, even after certificate expires. Proof of time Shows time of signing, but relies on local computer clock. Proves exact signing time from an independent, trusted source (TSA). Security level Good for basic authentication. High security for legal and archival needs, prevents backdating.

Timestamp Official Record in Adobe Acrobat — How-to & AI prompts

AI prompts

2 ways to ask · copy any one

AExecute — “help me do it”Write a time-stamped, precise record of today's hearing in Courtroom [room=3]: capture who…+

Write a time-stamped, precise record of today's hearing in Courtroom [room=3]: capture who spoke, the motions decided, rulings, and any continuances; add this as an annotated layer to the official PDF minutes and save to the case folder by [deadline=5pm].

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

BImprove — “do it better”Before finalizing the hearing record for Case [case=2026-045] in Courtroom 3, surface the…+

Before finalizing the hearing record for Case [case=2026-045] in Courtroom 3, surface the dispositive rulings and any deadlines at the top, mark speaker attribution clearly, note objections and judge responses, and run a quick OCR check so text is searchable before saving to the case file.

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 you want to apply a timestamp LTV to in Adobe Acrobat.
2
Ensure the PDF is already digitally signed; if not, apply a digital signature first.
NoteA timestamp LTV can only be applied to a document that has a digital signature.
3
Right-click the existing signature in the document and select Validate Signature.
4
In the Signature Validation Status dialog, click Signature Properties.
5
In the Signature Properties window, click Show Signer's Certificate.
6
Close the certificate viewer and return to the Signature Properties window.
7
Click Validate Signature if prompted, then close the dialog.
8
From the main menu, go to File > Save As and save the document to embed the validation information.
Best practiceSome users recommend saving a backup before embedding LTV, as the process cannot be undone.
9
Right-click the signature again and select Add Verification Information (or similar, depending on Acrobat version).
NoteThis step embeds the timestamp and revocation data needed for LTV.
10
Save the document again to finalize the LTV information.

In the appWith the API

After you add LTV information, anyone can verify the signature’s validity even if the certificate is later revoked.

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

Glossary

words on this page

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

Long-Term Validation (LTV)Extra information added to a digital signature so it stays valid even if its certificate expires later.ExampleThe LTV information confirmed the signature was valid even though the original certificate expired.

Time Stamping Authority (TSA)A TSA is a trusted company that provides secure and accurate timestamps for digital documents.ExampleThe TSA verified the exact date and time a critical legal document was digitally signed.

The real tasks

the one, listed here

Capture an accurate, time-stamped record of what was decided in hearings so the court has an official account of proceedings.

FAQ

about this task

Open your PDF in Acrobat.
Go to 'All tools' > 'Use a certificate'.
Select 'Timestamp' to add a time from a trusted source.
After signing, right-click the signature and choose 'Add Verification Information' to include LTV data.

Long-Term Validation (LTV) ensures your digital signature remains valid even after the signing certificate expires. This is crucial for legal and archival documents. Without LTV, a signature might appear invalid over time, making it harder to prove its authenticity. LTV embeds necessary verification data directly into the PDF, protecting the signature's integrity for many years.

Without Long-Term Validation (LTV), your digital signature may appear invalid once your signing certificate expires. This is why it's important to add LTV data when you sign. LTV embeds the necessary information to prove the signature was valid at the time it was made, even if the certificate is no longer active.

You should use a trusted Time Stamping Authority (TSA) because it provides an independent and reliable source for the exact time. This ensures the timestamp is accurate and cannot be easily faked or changed. A trusted TSA adds a layer of security and legal proof to your document, showing precisely when it was signed or created.

Feature	Simple Digital Signature	Signature with Trusted Timestamp and LTV
Validity over time	May become invalid when certificate expires.	Stays valid long-term, even after certificate expires.
Proof of time	Shows time of signing, but relies on local computer clock.	Proves exact signing time from an independent, trusted source (TSA).
Security level	Good for basic authentication.	High security for legal and archival needs, prevents backdating.

Timestamp Official Record

When to use it

AI prompts

How to do it

Glossary

The real tasks

Who does this

FAQ

Sources

Adobe help