The New York Mercantile Exchange and its rival the Intercontinental Exchange, owners of the world's two largest energy futures exchanges, are in talks to settle out of court a three-year legal dispute over pricing.

Both exchanges are keen to remove uncertainty from the legal action as ICE, the Atlanta-based electronic commodities exchange, is preparing for an initial public offering this summer, while Nymex intends to decide its future ownership structure by the end of this month.