Hedge fund manager Stanley Druckenmiller is closing his firm Duquesne Capital Management and plans to open a family office, according to Bloomberg.

“For 30 years I’ve been responsible for managing client money and it’s been a joy, but at some point I need to move on. Thirty years is enough,” he told the news service.

Duquesne Capital, which oversees $12 billion, has never had a losing year but is down 5 per cent so far in 2010.

Druckenmiller will open a family office to oversee some of his wealth, estimated at $2.8 billion by Forbes magazine, after he winds down the firm and returns money to clients sometime in 2011. He told Bloomberg he will invest with Duquesne portfolio managers who are planning to open their own hedge fund.