A merchant has the option to participate in Corporate Purchase Card (CPC) transactions. These are also known as "Level II" and "Level III" transactions and are for B2B purchases. In order to achieve the proper interchange rates for these transaction types, additional data elements are required to be passed to the card issuer. This is done by populating the CPCReq field in a CreditSale, CreditAuth, CreditOfflineSale, CreditOfflineAuth, RecurringBillingAuth, or RecurringBilling transaction. Level II data can be included directly in the transaction request or via CreditCPCEdit; Level III can only be sent via CreditCPCEdit.