Check if document was modified after signature

Aspose.PDF Product Family
1

Good evening,

I’m having trouble understanding how can I check if a document was modified after it was signed.

With AdobeAcrobat pdf it’s possible do make certain changes that dont break the signature. If these changes are made method CoversWholeDocument() returns false, however adobe recognizes that the changes have been made but don’t affect the document content itself.

My objective is to verifiy that the document content hasn´t been changed after it had been signed, regardless if it was 1 person or n people signing.

2

@645770

Any change to signed PDF invalidates the signatures. You can verify the signature validity using Aspose.PDF. However, if it does not help, please share some more details including sample file and screenshots so that we can investigate and share our feedback with you accordingly.

3

The example i’m using is a document that when opened with acrobat reader and do a save as…Adobe reader asks the user if it’s to enable ltv, if the user says yes, this breaks the signatures coverage on the document. I understand the document was changed but enabling ltv on signatures should’t affect signature coverage. How can I keep signature coverage in this case?

4

@645770

Would you kindly share your sample PDF document with us. We will further proceed to assist you accordingly.