October 19, 2011 - The European Commission is this week meeting to finalise the details of a new set of rules governing competition and transparency in the capital markets, with implications for high frequency traders, execution venues, clearing firms, and the over-the-counter markets.The updated guidance to the four-year old Markets in Financial Instruments Directive (MiFID) has been the subject of much political jousting and lobbying, with the Commission inviting more input from the buy side and taking a tougher stance on risk management and post-trade transparency.

The new Markets in Financial Instrument Regulations (MiFIR) are likely to be far more prescriptive than the predecessor Directive, which was drawn up in an effort to introduce more competition into deregulated markets. For a start the new rules will be binding on EU member states, leaving little wriggle room for nations to protect their domestic markets.

Leaked copies of the final guidance indicate a liquidity pumping crack down on computer-driven trading strategies with requirements for HFT firms to continue to post firm quotes throughout the trading day "regardless of prevailing market conditions".

The new rule book will also seek to level the playing field between competing stock exchange venues, multilateral trading facilities and broker crossing networks and break down the barriers between siloed clearing houses. The over-the-counter markets are also expected to diminish in size as regulators push more bilateral derivatives trading over electronic exchanges and central clearing facilities.