With just 12 months left until the introduction of a new rulebook that will transform Europe’s trading landscape, many of the regulations remain clouded in uncertainty, according to market participants.

The Markets in Financial Instruments Directive, known as Mifid II, comes into effect on January 3, 2018. Several crucial aspects have to be clarified by the European Securities and Markets Authority, or Esma, the Paris-based body responsible for turning the rules into a practical set of standards. One glaring uncertainty is that despite referring to financial instruments in its name, there is no clear definition of what constitutes a financial instrument.