Swiss banking regulators are recommending criminal action against Laxey Partners, the $2bn London hedge fund, for breaching disclosure rules by using contracts for difference secretly to build a big stake in the country’s biggest building services company.

The Swiss Federal Banking Commission (EBK) found that the activist hedge fund “parked” stakes with banks in order to circumvent disclosure rules, a move that sparked an outcry from the management of the target company, Implenia, when Laxey took a 22 per cent stake.