The fact that you presumably emailed the document back to them leaves a huge forensic trail.
The alternative proposal, or at least one of them, as I understand it is you upload the pdf to some site hosted by the counter party, where they would also control nearly all logs.
Because you signed using your private key.
How do you do a cryptographic signature in Apple Preview?
By downloading Acrobat Reader instead.
So nothing to do with the context of the thread.
Lol, exactly
how will they prove they didn't forge mine by making a fake account/e-mail address?