Chicago Mercantile Exchange Holdings Inc. and CBOT Holdings, Inc. announce they have signed a definitive agreement to merge the two organizations. They say this creates an extensive and diverse global derivatives exchange, reaching $25 billion.

The combined company, named CME Group Inc., a CME/Chicago Board of Trade Company, is expected to transform global derivatives markets, creating operational and cost efficiencies for customers and exchange memb while delivering significant benefits to shareholders. Corporate headquarters of the combined organization will remain in Chicago.

The combined company will have an average trading volume approaching 9 million contracts a day.