The Chicago Mercantile Exchange, the world's largest derivatives market, suffered a double blow yesterday as a rival won the exclusive right to trade some of its contracts and members refused to trade a groundbreaking new product.

The IntercontinentalExchange, the US energy market vying with the CME to buy the Chicago Board of Trade, said yesterday it had reached an agreement with the Russell Investment Group to acquire the exclusive rights to trade futures and options based on the vendor's benchmark US stock indices.