Exchange-operator CME Group expands private trades in grain markets

Exchange-operator CME Group Inc will allow a type of privately negotiated transaction in all its agricultural markets for the first time on Monday, splitting traders who predict the move will either improve or hurt transparency.

The company, which owns the Chicago Board of Trade (CBOT) and Chicago Mercantile Exchange, will expand the use of transactions called block trades in its grain and livestock futures and options, such as corn. It already permits the trades in other markets ranging from Black Sea wheat to Eurodollars. Block trades are large, privately negotiated deals struck away from the broader market by phone or otherwise