This wiki describes what and how to implement digital signatures in a PDF.
Overview
A digital signature is a mathematical technique used to validate the authenticity and integrity of document. It's the digital equivalent of a handwritten signature or stamped seal, but it offers far more inherent security. A digital signature is intended to solve the problem of tampering and impersonation of electronic document. Digital signatures can provide evidence of origin, identity and status of electronic documents, transactions or digital messages. Signers can also use them to acknowledge informed consent.
In many countries, including the United States, digital signatures are considered legally binding in the same way as traditional handwritten document signatures.
Pre-requisite
When you receive a digitally signed document, both Adobe Reader and Acrobat ask three key questions to validate the signature:
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