Editing a Signed PDF

[Guest]

I know the default answer will be that it stops you by design, the problem is that I'm getting an abnormal result.

I have users in an accounting area that want to edit a pdf to add PO's and other numbers after some initial signatures. I know modifying the text after a signature is a security concern which is why Adobe doesn't allow it. The problem is that one user CAN edit the document for some reason and the other person is asking why.....

When I try to edit the PDF, it gives me the error "This document has been signed and can not be edited". I also get a similar(maybe exact) message from someone else. My version is Adobe Acrobat Standard DC and the other person that has the same error has Adobe Acrobat Pro XI 11.0.12. The person that CAN modify the pdf, despite the signatures has Adobe Acrobat XI 11.0.18.

I do probably need to update the one user's Acrobat but mine is newer and I have been told that editing a PDF after a signature shouldn't be allowed anyways.

Any idea why one person can edit the pdf when they shouldn't?

[woopwoop56284148]

True, the validity of the signatures depend on who and what the document is for. If it's for purposes like accounting where you need to add transaction numbers etc post-signing, then this is a great way around, as although the security certificate is no longer present, the signatures will still be present on the saved file. You can always save the original file and the non-secured file so that you can prove the signatures are valid.

[try67]

Without the digital certificate the "signature" you see on the page is meaningless.

[woopwoop56284148]

Any reviewers of the document can always cross-check the signatures with the document history/ final audit report page processed on the end of every document.

[Test Screen Name]

The mark on a page, which might happen at the same time as signing, should NOT be called a signature. It can be faked in seconds. Your staff need to be trained to IGNORE any marks on the page, no matter how official looking, and to check the actual digital signature. All the "clever" tricks suggested above ignore this basic rule, and mix up the page marks with the actual signature. 

[woopwoop56284148]

Indeed, which is why it is a good idea to keep a record of the signed document with the security certificate intact and unaltered, and any edits to do on a separate copy.