Investment Technology Group has seen a fall in its share of European equity trading in the week after revealing it may pay a record fine to the Securities and Exchange Commission over its US dark pool.

The agency broker's average share of total equity trading by turnover in Europe, the Middle East and Africa fell by "single digit percentage terms" between July 30 and August 6, according to people familiar with the situation. That figure included trades executed through ITG's electronic brokerage and its platform business, which includes its dark pool called Posit, the people said. The European version of Posit accounts for around a third of ITG's business in the region.