PDF digital signature

[Karthick5E6F]

If i am receiving a pdf file with digital signature.when I try to edit it's showing I am not allowed to edit.If I copied to local drive then I edited the pdf .it will be informed to Signature person ?? Or Abode will notify when the pdf is edited ?? 

[MikelKlink]

Nobody will be automatically informed about you changing a signed PDF.

Merely when you yourself forward the manipulated PDF to someone else, that person can validate the signature and see whether your changes invalidated the signature or not.

[try67]

You're not allowed to edit because it is signed. That's one of the main reasons to digitally sign a file, to ensure it's not edited after it was signed.

[Abambo]

A file that is digitally signed cannot be changed without breaking the signature. It's the same as in the paper world. As soon as a contract is signed, you can't change it any more because that would break the signature.

If you want or need to modify it, ask the creator of the file to get an unsigned copy, modify and let it sign again...well, if the parties agree with your changes.

[MikelKlink]

A file that is digitally signed cannot be changed without breaking the signature.

Well, if we're talking about integrated pdf signatures, this is not completely true - as long as one changes the pdf using incremental updates, the signature remains intact cryptographically (because the signed byte ranges are stored in the signed data). And as long as one merely applies changes allowed by the document DocMDP settings, it even remains valid according to spec.