Certify PDF Files

Use certification to confirm that you are the author of a document and to control what changes are allowed.

When you certify a document, you define permitted actions. If a user makes a change that is not permitted, the certification becomes invalid.

Certification rules

• A PDF can be certified only once
• A certified PDF can be digitally signed multiple times, if permissions allow
• If an unauthorized change occurs, the certification is revoked

Note: When you share a certified PDF, the viewer must support certification and digital signatures

Permitted actions

When you certify a document, select one of the following options:

• Disallow any changes
  • Prevent all changes, including editing, commenting, form filling, and signing
  • If any change occurs, the certification becomes invalid
• Allow form fill and signing
  • Allow form filling and signing only
  • Prevent all other changes
• Allow commenting, form fill, and signing
  • Allow commenting, form filling, and signing
  • Prevent all other changes

To certify a PDF

1. On the Protect tab, in the Certify Document group, click Certify
2. In the Certify Profile Wizard, select permitted actions
3. Click Next
4. Select a digital ID
5. Select whether to show the certificate
6. Click Next
7. If the certificate is visible, click a location on the page
8. In the Certify Document dialog, do the following:
   1. Select or enter a reason
   2. Select to save to the current file or a new file
   3. Select the certificate appearance
9. Click Finish
10. Click Apply

Document behavior after certification

After certification:

• The document allows only the selected actions
• Other actions are not allowed
• If an unauthorized change occurs, the certification becomes invalid

Reasons to certify a document

Use certification when you want to:

• Confirm that you are the author of the document
• Confirm the document content
• Control allowed actions
• Allow signing, form filling, or commenting without invalidating the certification

Additional information

• Certification helps protect document integrity
• Certification can prevent actions such as editing text or inserting pages
• Certification is different from a digital signature because it defines allowed actions