Patent ID: 7461028

Claim:
A method for authorizing purchases by an owner of an account previously established with a bank, the owner wanting to purchase an item from a merchant, the method comprising the step(s) of: providing a plurality of authorization parameters available for use in calculating an authorization code associated with a specific transaction to purchase the item; defining a selected subset of the plurality of authorization parameters; establishing respective authorization parameter data for each of the selected authorization parameters; calculating the authorization code corresponding to the established respective authorization parameter data associated with said specific transaction; providing the authorization code associated with said specific transaction to the owner; providing the authorization code associated with said specific transaction to the merchant; receiving the authorization code associated with said specific transaction and transaction data from the merchant at the bank; calculating a confirmation authorization code from the transaction data corresponding to the established respective authorization parameter data; and comparing the authorization code associated with said specific transaction with the confirmation authorization code to determine whether or not to approve the transaction.