Abstract: Notifications regarding content transactions may be received at a high rate in systems providing content to a large number of customers from a number of vendors. Each notification may contain multiple fields of information about the transaction. Business rules for determining amounts that should be invoiced for content transactions have fields of information for matching to nonfictions. As each notification is received: (1) a rule having fields of information that match fields of information contained within the notification is located; (2) an amount that should be invoiced for the transaction is determined from the located rule; (3) a line item in the determined amount is added to an open invoice for the vendor related to the content transaction that the notification is about; and (4) the updated open invoice may be saved. These steps may all be performed in real time, without copying or redistributing data in the original notification.