Patent ID: 8791822
Filing Date: 2014-07-29
Classification: G07D

Abstract:
1. A method of detecting duplication of currency, said method comprising steps of: interrogating a radio frequency identification (RFID) chip embedded in a currency bill to cause said RFID chip to return stored information, said stored information including information uniquely identifying said currency bill; receiving a response signal from said RFID chip comprising RFID chip information; comparing said RFID chip information to RFID information of currently circulating genuine currency, said comparing step providing a validation of said currency bill if said RFID chip information corresponds to said RFID information of currently circulating genuine currency, said comparing step providing an indication that said currency bill is not legitimate if said RFID chip information does not correspond to said RFID information of currently circulating genuine currency; if said validation is provided, comparing said validation to a previous validation; and determining a likelihood of a duplicated RFID chip based on said comparison of said validation to said previous validation, and altering said RFID chip by storing surrogate information on said RFID chip, which surrogate information is a surrogate for and determined from said information uniquely identifying said currency bill and constitutes a highly secure cryptographic key for determining an identity of said currency bill and which varies in accordance with variable conditions associated with a given validation so as to make it unlikely that said RFID chip has been duplicated.