Fortress Investment Group, the alternative fund group that went public in February 2007, announced a $55m loss for the quarter.

Fortress has $35bn under management, up 23 per cent from a year ago. It generated management fees of $150m in the quarter. But it conceded on Thursday that it had not earned any significant performance fees so far this year.

Many investors fear that a public listing leads firms to concentrate on increasing their assets under management instead of focusing on the performance of their funds.

Fortress is not the only investment group struggling to generate performance fees. GLG in a conference call earlier this week noted that their hedge funds were well below their peak and would have to gain more than $700m before they started generating performance fees.