US Patent 7631804 Payment card financial validation processing center

A method for validating a payment card financial transaction includes receiving a financial transaction approval request message derived from a payment card that is able to change its magnetic card data as elicited by a card reader. Out-of-sequence transactions encoded in a dynamic number included in said magnetic card data are detected. The dynamic number is compared with a last valid number that was previously stored in a database. An approval message is issued to enable the completion of a financial transaction with the payment card.