An application that seals your PDF with a public key of the recipientAloaha PDF Crypter is the perfect choice to prohibit re-distribution of confidential documents or sell documents/ebooks online.
Standard PDF Encryption with owner and user passwords used to be the only PDF protection. Unfortunately passwords do not stop somebody of passing the PDF document on to somebody else. Even worse is the fact that PDF passwords can be removed very easy. The owner password for example can be removed in a matter of seconds without even knowing the passwords.