A group of influential buyside trade bodies has come out in support of a controversial identifier used in reporting derivatives trades, while Europe’s top markets regulator says that those opposed are not reading the rules correctly.

European regulators will mandate the use of the International Securities Identification Number for reporting some derivatives trades, as part of the review of the Markets in Financial Instruments Directive. This is a unique, 12-character code that individually identifies a particular security and is part of the reporting overhaul included in Mifid II.