US Patent 10423938 Identifying negotiable instrument fraud using distributed ledger systems

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for receiving first information of a first negotiable instrument, at least a portion of the first information including a first unique instrument identifier physically encoded on the first negotiable instrument, the first unique identifier uniquely identifying the first negotiable instrument among a plurality of negotiable instruments, transmitting the first information to a distributed ledger system, the distributed ledger system maintaining a blockchain that records transactions associated with a plurality of negotiable instruments, receiving first validation information from the distributed ledger system, the first validation information indicating that first negotiable instrument has not already been accepted, and accepting the first negotiable in response to the first validation information.