(15)To avoid charging clients multiple times for the same provision of market data when buying them from different providers and vendors, when requested by the client, market data should be offered on a per client basis. The CTPs collect data from trading venues and APAs and consolidate those data into a continuous electronic live data stream providing core market data and regulatory data. Therefore, the provision of those data by CTPs should be considered as distinct from the provision of market data by trading venues and APAs. Consequently, CTPs should be able to charge a fee to their client even if that client is charged for market data by a trading venue or an APA.