A method for use by an operator of a system for trading of financial instruments allows the operator to differentiate between the information a user of the system is given access to regarding trades which are made outside of the system and then reported to the system, so called off-exchange trades. The operator defines a first set of boundaries within which the off-exchange trades will be accepted by the system. The operator also defines which sub-sets of a set of information about the trade will be disseminated to users of the system. The definition of the boundaries and the sub-sets of information are defined independently of each other.