The most popular trade is to be long the dollar and short the euro.
The consensus view is that the U.S. economy is relatively strong, giving Janet Yellen's Fed the confidence to ease off of ultralow interest rates in place since the aftermath of the financial crisis in 2008. At the same time, Europe is seen as more fragile, and central bankers there have pledged to keep interest rates low by buying 60 billion euros of bonds a month.
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"While the United States is showing strong signs of growth and is engaging in a trend of gradual tightening by the Fed, weak growth and heightened deflationary risks in Europe and Asia are being fought with increased monetary expansion," Gávea Investimentos wrote in a private letter to clients of macroeconomic-focused hedge fund in March.
Gávea is the $6 billion Brazil-based alternative asset management unit of JPMorgan Chase and is led by former Braziian central bank president Arminio Fraga Neto and Luiz Henrique Fraga. A spokesman at JPMorgan declined to comment.
The Gávea "macro" fund letter noted that currency bets were its largest of all asset classes; the wagers include long positions in the dollar and shorts on the euro and other currencies. Such bets have pushed the main Gávea Fund up an estimated 6.8 percent net of fees this year through March 20, according to performance information obtained by CNBC.com.
Other prominent hedge fund firms who currently have the long dollar versus short euro bet on include Ray Dalio's Bridgewater Associates, Alan Howard's Brevan Howard, Leda Braga's Systematica Investments, Paul Tudor Jones' Tudor Investment, Louis Bacon's Moore Capital Management and Andrew Law's Caxton Associates, according to people familiar with their positioning.
Representatives for those firms declined to comment or did not respond to a request.