Rubicon Fund Management, the hedge fund manager, has seen its sole fund shrink by over 80% since the departure of a fund manager in January. It has launched legal actions against two of its former fund managers and the employee of a former investor.

The Rubicon Master fund had assets of $1.65bn in January when fund manager Tim Attias left the firm. He announced his intention to leave the previous month after he and co-chief investment officer Santiago Alarco had a row with Rubicon co-founders Paul Brewer and Joe Leitch, according to court documents.