Patent ID: 7818812

Claim:
System for creating a document and for later verification of authenticity and negotiation of the document comprising: a creating workstation for receiving and placing critical information in a critical field of the document; logic instructions stored in the creating workstation for obtaining a description of a unique authenticator item that is independently identifiable so as to be constituted for difficulty of counterfeiting, the unique authenticator item being separate from the document, the document being capable of cancellation by defacing or destroying the unique authenticator item; a communication network connected to the creating workstation for communicating the critical information from the creating work station to an authorizing computer; the authorizing computer connected to the communication network, the authorizing computer comprising computer readable logic instructions stored in the authorizing computer for calculating security information by combining the critical information and a description of the authenticator item that is independently identifiable so as to be constituted for difficulty of counterfeiting which is separate from the document, using a cryptographic security function; the creating workstation connected to the communication network for receiving the security information and logic instructions stored in the creating workstation for placing the security information in a security information field of the document; an acceptor workstation connected to the communication network, the acceptor workstation having reading means for reading critical information and security information from the document and calculating trial security information from the critical information and a description of an authenticator presented with the document; computer readable logic instructions recorded in the acceptor workstation for comparing the security information and the trial security information to determine authenticity of the document; computer readable logic instructions recorded in the acceptor workstation for determining that the document is an authentic negotiable document when the trial security information and the security information read from the security information field are equal and the authenticator is present with the document; and computer readable logic instructions recorded in the acceptor workstation for determining that the document is an authentic copy of the negotiable document when the trial security information and the security information read from the security information field are equal and the authenticator is not present with the document; and computer readable logic instructions recorded in the acceptor workstation for determining that the document is not an authentic copy of the negotiable document when the trial security information and the security information read from the security information field are not equal.