RAB Capital, the US hedge fund manager that has already restructured two of its portfolios since September because of market volatility, has de-listed a fund which had assets frozen following the collapse of Lehman Brothers, in a further sign of how financially debilitating the US bank's demise has been.

RAB Multi-Strategy Enhanced withdrew its listing on the Irish Stock Exchange on October 31, and a spokesman for the $43m (€33.4m) portfolio said: "The fund's board is reviewing options for RAB Multi-Strategy." Managers have suspended calculating the value of the portfolio.