ITG, the US agency broker and dark pool operator, has said it is close to a settlement with regulators that would potentially mean it paying a $20.3 million fine. Such a penalty would be the biggest yet levied on an operator of a dark pool.

The US broker said on July 29 that it had negotiated a probable settlement with the Securities and Exchange Commission over an electronic market-making initiative that it piloted over 16 months in 2010 and 2011.