(3)For some financial instruments such as for derivatives it may not always be possible to determine unambiguously the particular asset class to which that instrument belongs since the determination of an asset class depends on which characteristics of the financial instruments are considered to be the decisive ones. Similarly, it may not always be possible to unambiguously determine which other criteria a type of data meets. To ensure that market participants purchasing data from a particular trading venue receive a consistent data set, it is necessary to require market operators or investment firms operating a trading venue to determine in those cases where the disaggregation criteria cannot be applied in an unambiguous manner which criteria a financial instrument or type of data should be deemed to meet.