CME Group Inc. Announces Preliminary Results of Self-Tender Offer

The depositary for the tender offer has advised CME Group on a preliminarybasis that approximately 1,646,450 shares of Class A common stock wereproperly tendered and not withdrawn in the tender offer, including 116,448.75shares that were tendered by notice of guaranteed delivery. Based on thispreliminary count by the depositary, CME Group expects to accept for purchaseapproximately 1,646,450 shares of its Class A common stock, representingapproximately 3.0 percent of the outstanding Class A common stock, at apurchase price of $560 per share for a total cost of approximately$922 million, excluding fees and expenses relating to the tender offer. Giventhat the preliminary number of shares tendered is less than the number ofshares that CME Group offered to purchase, no proration will be required.

The results announced today are preliminary and subject to verification bythe depositary. The determination of the number of shares to be accepted forpayment is subject to final confirmation of the proper delivery of the sharestendered and not properly withdrawn, including shares tendered by notice ofguaranteed delivery. The actual number of shares to be purchased will beannounced following the completion of the verification process. Payment forthe shares accepted for purchase will occur promptly thereafter. CME Groupintends to initially fund the purchase of shares with a combination ofproceeds from the issuance of commercial paper and cash on hand.

The tender offer was made in connection with the merger of CBOT Holdings,Inc. with and into CME Group. The merger agreement required CME Group toundertake the tender offer after the closing of the merger, which occurred onJuly 12, 2007.

Lehman Brothers Inc. acted as lead dealer manager and William Blair &Company, L.L.C. acted as co-dealer manager for the tender offer.

Questions regarding the tender offer should be directed to D.F. King &Co., Inc., the information agent for the tender offer, at (800) 697-6975(toll-free).

About CME Group

CME Group () is the world's largest and mostdiverse exchange. Formed by the 2007 merger of Chicago Mercantile ExchangeHoldings and CBOT Holdings, CME Group serves the risk management needs ofcustomers around the globe. As an international marketplace, CME Group bringsbuyers and sellers together on the CME Globex electronic trading platform andon its trading floors. CME Group offers the widest range of benchmarkproducts available across all major asset classes, including futures andoptions based on interest rates, equity indexes, foreign exchange,agricultural commodities and alternative investment products such as weatherand real estate. CME Group's Class A common stock is traded on the New YorkStock Exchange and the Nasdaq Global Select Market under the symbol "CME."

The Globe logo, CME, Chicago Mercantile Exchange, CME Group, Globex andE-mini, are trademarks of Chicago Mercantile Exchange Inc. CBOT and ChicagoBoard of Trade are trademarks of the Board of Trade of the City of Chicago.All other trademarks are the property of their respective owners. Furtherinformation about CME Group and its products can be found at.

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