Some of the giants of the hedge fund world have made billions betting against the yen in recent months, marking a return to form for some blue-blood investors that stumbled after the financial crisis.
So-called "global macro" managers, which speculate on economic shifts by trading currencies, bonds and derivatives, have reaped their biggest gains in years trading on the Japanese currency.
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Caxton Associates, the Anglo-US fund run by former Goldman Sachs partner Andrew Law, made nearly 10 percent for investors in the past three months while Paul Tudor Jones' Tudor Investment Corporation and Louis Bacon's Moore Capital have seen their flagships rise 9 percent. In comparison, global macro hedge funds on average made just 3.5 percent in the preceding three years, according to Hedge Fund Research.