(11)Operators of trading venues should, for each order received, record and maintain the order type and the related specific instructions which together determine how each order is to be handled by their matching engines, in accordance with their own classifications. This detailed information is essential for competent authorities to be able to monitor, as part of its market abuse surveillance, trading activity in a given trading venue order book and in particular to replicate how each order behaves within the order book. However, given the broad range of existing and potential new order types designed by operators of trading venues and the specific technicalities attached to the latter, the maintenance of this detailed information according to the operators' internal classification system may not currently allow competent authorities to replicate the order book activity of all trading venues in a consistent manner. Therefore, for competent authorities to be in a position to exactly locate each order within the order book, operators of trading venues should also classify each order received either as a limit order where the order is tradable or as a stop order where the order becomes tradable only upon the realisation of a pre-determined price event.