Nymex is the world's largest, physical commodities futures exchange, and features contracts for crude oil, gasoline, natural gas, and electricity; and precious metals such as gold, silver and copper. CME's product strengths include interest rates, foreign exchange, stock indexes, and agricultural commodities.

A logical deal

Independent stock analyst C. Leonard Bauer told BloggingStocks Monday a potential CME/Nymex could get done, "as the logic is there". Bauer added that he does not have a rating on either company, nor does he own shares of either company.

Nymex's products have almost no overlap with CME's strengths in interest rates, foreign exchange, stock index and agricultural commodities, he said. Almost, he underscored. However, a CME/Nymex deal would have "an 80% or better market share in U.S. futures and futures on option volume," he said. Any proposed deal is subject to review by the U.S. Department of Justice.

"The onus would be on CME to demonstrate to public officials how in the electronic age, the number of electronic exchanges would counteract CME's market dominance in that segment," Bauer said. "The issue is not one of global competition. The issue is 'how will a CME/Nymex merger lower trading prices and improve services?' If they can demonstrate that, then that dimension, and the product mix, and economies of scale points would most likely put the deal in motion."