Lawyers filed a complaint in a Minnesota court last week, accusing Equisure and a number of its directors of deliberately publishing false and misleading information about the company's financial performance as part of an orchestrated scheme to defraud shareholders.
The investments of thousands of shareholders were rendered worthless in August, when US regulators suspended Equisure's shares on the American Stock Exchange and began investigations into allegations of book-keeping fraud and insider dealing after a tip-off by Belgian police.
Equisure's shares, which had more than doubled in value from $6 (pounds 3.75) to over $15 within the space of five months, had been one of the Exchange's star performers, soaring on announcements of lucrative insurance deals in the US and the UK, and strong financial results.
But court documents cast doubt on Equisure's success. They accuse Peter Uttley, Equisure's chairman and a former campaigner for loss-making Lloyd's Names, and Barrie Harding, a former Lloyd's broker and until recently Equisure's chief executive, of being involved in the fraudulent manipulation of Equisure's share price and publishing misleading information.
The complaint also names Moores Rowland International, which audited Equisure's accounts through its Minnesota affiliate, Stirtz Bernards Boyden Surdel & Larter, of lending credence to Equisure by allowing its name to be used on the company's audit."
Charles Maynard, chairman of Moores Rowland International, denied the claims.