Amex files blockchain proof of payment patent

Systems and methods for blockchain based proof of payment — USPTO — “The system may be used to unlock a hotel, rental, or shared economy property door using the card (eg that was used for the payment) to look up proof of payment on a blockchain… In another example, the system may be used to provide ticketless access to venues (eg movie theater, sports event, concert, etc) to a customer… In still another example, the system may enable access control to rental vehicles (eg bike, boat, or car) to a customer in response to swiping the card.”