Patent ID: 8458092

Claim:
A method for transaction adjustment, comprising the steps of: facilitating presentation of a payment device having an offline balance to an offline terminal in connection with a putative transaction, said transaction comprising a vend having a vend value, wherein: said payment device comprises: a body portion; a payment device memory associated with said body portion and containing said offline balance; and at least one payment device processor associated with said body portion and coupled to said memory; and said offline terminal comprises: a reader module; a terminal memory associated with said reader module; and at least one terminal processor coupled to said memory; facilitating detection of an irregularity with said putative transaction, said irregularity comprising a vend failure; adjusting said offline balance, responsive to said detection, said adjusting being carried out, via offline-terminal interaction between said at least one payment device processor and said at least one terminal processor, communicating through said reader module, without the use of a security module and cryptographic keys in said offline terminal, wherein said adjusting comprises refunding said vend value to said offline balance; and dispatching, from said offline terminal, a terminal-transformed number, said terminal-transformed number comprising an unpredictable source number transformed in accordance with a non-invertable transformation scheme; wherein said adjusting step further comprises dispatching, from said offline terminal, said source number, in a form for subsequent transformation by said payment device.