A customer who does not receive his goods or services, or says he did not place an order, can ask his issuing bank to charge back the merchant. The Issuing Bank sends the charge back request to the merchant bank, which forwards it to the merchant asking to validate the charge. Information such as the amount, an invoice or folio, customer signature, or shipping documents, and the shipping address (used in AVS during the authorization) are needed to defend against a charge back.