While financial services firms in the U.S. have been gearing up this year for the full implementation of Reg NMS, companies in Europe have been preparing for MiFid. (Well, actually only 8 of the 27 EU member states have so far implemented the legislation into their domestic law.)

Now, the head of the Centre for European Policy Studies (CEPS) is urging the European Commission to look into the similarities and differences between MiFid and Reg NMS.

Karel Lannoo, chief executive of CEPS, says both pieces of legislation came into effect at around the same time, and both are aimed at “updating regulation to reflect technological changes and market developments.”

There are also many differences: while Reg NMS is prescriptive, MiFid is more principle-based. The two pieces of legislation also differ in their definition of best execution, as well as in the structure of the markets and the role and powers of supervising authorities, Lannoo says.

However, both regulations focus on best execution in equity trading - and both are expected to provide markets with the incentive to adopt technologies that allow them to be more responsive to the speed of execution, says Lannoo.

In a CEPS paper, he suggests that all the similarities between MiFid and Reg NMS are simply too great to ignore.

With the opening of the first transatlantic exchange, NYSE-Euronext, Lannoo also predicts that integrated transatlantic trading floors will soon emerge, facilitating the execution of trades under the most favorable regime.

Lannoo says the implementation of MiFID will provide a unique opportunity for the European Union to negotiate a mutual recognition agreement with the U.S.

This would allow reciprocal access to exchanges and broker-dealers, and therefore give European exchanges and banks much better access to the US market, Lannoo says.

Regulatory match made in heaven, anyone?