Patent ID: 8412640

Claim:
A method comprising a plurality of steps each being performed by hardware executing software, wherein the steps include: reading data at a point of service (POS) terminal at a merchant, wherein: a payment device is read by the POS terminal when presented in proximity thereto by a consumer seeking to conduct a transaction for a good or service from the merchant; the payment device includes an encryption code for a Primary Account Number (PAN) of an account issued to the consumer by an issuer; the POS terminal is not in real time communication with the issuer; the encryption code is an encryption of at least the PAN; and the data read from the payment device includes the encryption code and a non-PAN signature that corresponds to the PAN; without decrypting the encryption code to derive the PAN: checking a list of non-PAN signatures maintained by the POS terminal to determine if the non-PAN signature read from the data on the payment device is on the list; and permitting, on the basis if whether the non-PAN signature is on the list, the consumer to complete the transaction with the merchant; and sending, from the POS terminal, information corresponding to the transaction, including the encryption code read by the POS terminal, for delivery to and use by an acquirer for the merchant for clearing and settlement with the issuer of the account to receive payment for the transaction from the account.