George Soros, the legendary US speculator turned billionaire philanthropist, will close his hedge fund to outsiders and use it solely for managing family money, media reports said Tuesday. The move is the latest step in the winding down of Soros\' Quantum Fund, which he used to make a now-famous 1992 bet against the British pound that earned him over $1 billion and the nickname \"the man who broke the Bank of England\". Tighter regulations have compelled Soros Fund Management to return capital to the last remaining outside investors in its Quantum Group of Funds, two of Soros\' sons wrote in a letter to investors, a copy of which was obtained by The New York Times. \"An unfortunate consequence of these new circumstances is that we will no longer be able to manage assets for anyone other than a family client as defined under the regulations,\" Jonathan and Robert Soros said in the letter, a copy of which was posted on The New York Times\' website. Less than $1 billion of the $26 billion managed by the fund belongs to outsiders, the newspaper reported. The fund has effectively operated as a family concern since 2000 when it stopped accepting new outside investors. Soros, 80, was listed as the world\'s 46th richest person by Forbes magazine earlier this year, with a fortune of $14.5 billion. Born in Hungary, Soros survived the Nazi occupation despite his Jewish roots and emigrated to Britain and later the United States after World War II. In recent years he has given away billions of dollars for philanthropy.