Druckenmiller says he will finally retire after 30 years at the top

Stanley Druckenmiller, a key player in George Soros’ famous bet against the pound that earned him $1bn (£640m), said he is closing his firm after 30 years.

In a letter sent to his 100-plus investors, Druckenmiller, chief executive officer of Duquesne Capital Management, said “competing in the markets over such a long timeframe imposes heavy personal costs.”

His Duquesne Capital Management, which has never had a losing year, is down five per cent in 2010.