Cardholder Orders

A Cardholder Order is more detailed than a Shopping Cart Order. It requires a cardholder element. A cardholder element in turn requires a card and some minimum attributes of the cardholder’s identity.

At a minimum, the card entity includes the card number and the expiry date on the card. The definition also includes the ability to incorporate debit card and CVC verification as options.

Including additional information of the cardholder in the message can be used for demographic profiling and fraud detection. The question of how much cardholder data should be required is a business case question. These same arguments hold for the collection of order fulfillment attributes such as shipping addresses. Any decision would also involve legal implications for the sharing of consumer data between independent corporations.

The Cardholder Order message also includes a shopping_cart element almost identical to a Shopping Cart Order message except that in a Cardholder Order, the timestamp and order numbers are required elements. The inclusion of these requirements provides idempotency checks to ensure that a consumer did not make multiple purchases within a given transaction window because of some network error. This removes the possibility of incurring inadvertent duplicate charges.

Again, a MAC ensures that the transaction originated from the merchant and was unaltered during transmission.