Turning a profit in over-the-counter clearing is a tough slog. Some of Europe’s biggest banks – such as Deutsche Bank and RBS – have all but quit the business. Others have pulled back significantly. The big US banks – Citi, JP Morgan, Morgan Stanley and Bank of America – have been dominant for much of the past decade, bolstered by their scale and sizeable balance sheets.

But changes to capital rules, coupled with Brexit uncertainty and fears of concentration risk, may be aiding a European