Patent ID: 8131642

Claim:
A method of controlling the value of at least one proposed on-line transaction involving a token associated with an authorised user and which transaction will involve a transfer of funds from an account of the user with a financial institution and which account is associated with the token, the method using a transaction authorisation system comprised of a terminal associated with the user and a transaction authorization station, the method comprising the steps of: enabling the user to select, by means of the terminal associated with the user, a base amount available from the user's account for future transactions, to thereby establish a maximum amount that the user may lose due to unauthorized use of the token; enabling the user to transmit, by means of the associated terminal, at any time prior to at least one proposed transaction a data message comprising pre-transaction authorization data relating to the at least one proposed transaction to the transaction authorization station; prior to the at least one proposed transaction, receiving at the transaction authorization station pre-transaction authorisation data relating to the at least one proposed transaction; the pre-transaction authorisation data comprising first time data relating to a time window within which the at least one proposed transaction must take place and first amount data relating to an amount, which is different from the base amount, and with which a value of the at least one proposed transaction must comply; at the time of each of the at least one proposed transaction, receiving at the transaction authorization station proposed transaction data comprising second time data relating to a time instant of said proposed transaction and amount data relating to a value of said proposed transaction; comparing at the transaction authorization station the proposed pre-transaction transaction data and the authorisation data; enabling said proposed transaction only if the proposed transaction data complies with the pre-transaction authorisation data; and at the end of the time window, automatically resetting the first amount data to the base amount.