News Release

CME Group Files Registration Statement Related to Proposed Acquisition of NYMEX Holdings Inc.

Wed Jun 11 2008

CHICAGO, June 11 /PRNewswire-FirstCall/ -- CME Group Inc. (NYSE: CME)(NASDAQ: CME) today announced the filing of a Registration Statement on Form S-4 with the U.S. Securities and Exchange Commission (SEC) containing a preliminary joint proxy statement/prospectus related to its proposed transaction with NYMEX Holdings, Inc. CME Group and NYMEX Holdings stockholders and members of NYMEX are expected to vote on the transaction and related matters later this year.

CME Group (http://www.cmegroup.com/) is the world's largest and most diverse derivatives exchange. Formed by the 2007 merger of the Chicago Mercantile Exchange (CME) and the Chicago Board of Trade (CBOT), CME Group serves the risk management needs of customers around the globe. As an international marketplace, CME Group brings buyers and sellers together on the CME Globex electronic trading platform and on its trading floors. CME Group offers the widest range of benchmark products available across all major asset classes, including futures and options based on interest rates, equity indexes, foreign exchange, agricultural commodities, and alternative investment products such as weather and real estate. CME Group is traded on the New York Stock Exchange and NASDAQ under the symbol "CME."

Forward Looking Statements:

This transcript may contain forward-looking information regarding CME Group Inc. and NYMEX Holdings, Inc. and the combined company after the completion of the merger that are intended to be covered by the safe harbor for "forward-looking statements" provided by the Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, the benefits of the business combination transaction involving CME Group and NYMEX Holdings, including future financial and operating results, the new company's plans, objectives, expectations and intentions and other statements that are not historical facts. Such statements are based on current beliefs, expectations, forecasts and assumptions of CME Group's and NYMEX Holdings' management which are subject to risks and uncertainties which could cause actual outcomes and result to differ materially from these statements. Other risks and uncertainties relating to the proposed transaction include, but are not limited to the satisfaction of conditions to closing; including receipt of shareholder, antitrust, regulatory and other approvals on the proposed terms and schedule; the proposed transaction may not be consummated on the proposed terms and schedule; uncertainty of the expected financial performance of CME Group following completion of the proposed transaction; CME Group may not be able to achieve the expected cost savings, synergies and other strategic benefits as a result of the proposed transaction or may take longer to achieve the cost savings, synergies and benefits than expected; the integration of NYMEX Holdings with CME Group's operations may not be successful or may be materially delayed or may be more costly or difficult than expected; general industry and market conditions; general domestic and international economic conditions; and governmental laws and regulations affecting domestic and foreign operations.

For more information regarding other related risks, see Item 1A of CME Group's Annual Report on Form 10-K for the fiscal year ended December 31, 2007 and Item 1A of NYMEX's Annual Report on Form 10-K for the fiscal year ended December 31, 2007 and additional updates to these risks contained in our Quarterly reports. Copies of said 10-Ks and 10-Qs are available online at http://www.sec.gov/ or on request from the applicable company. You should not place undue reliance on forward-looking statements, which speak only as of the date of this press release. Except for any obligation to disclose material information under the Federal securities laws, CME Group and NYMEX Holdings undertake no obligation to release publicly any revisions to any forward- looking statements to reflect events or circumstances after the date of this press release.

Important Merger Information

In connection with the proposed merger of NYMEX Holdings, Inc. ("NYMEX") and the CME Group Inc. ("CME Group"), the parties have filed relevant materials with the Securities Exchange Commission ("SEC"), including a joint proxy statement/prospectus regarding the proposed transaction. INVESTORS ARE URGED TO READ THE JOINT PROXY STATEMENT/PROSPECTUS REGARDING THE PROPOSED TRANSACTION, BECAUSE IT CONTAINS IMPORTANT INFORMATION. Investors are able to obtain a free copy of the joint proxy statement/prospectus, as well as other filings containing information about NYMEX and CME Group without charge, at the SEC's website (http://www.sec.gov/). Copies of the joint proxy statement/prospectus can also be obtained when available, without charge by directing a request to CBOT Holdings, Inc., Attention: Investor Relations, at 141 West Jackson, Chicago, Illinois 60604 or calling (312) 435-3500.

CME Group and its directors, executive officers and other employees may be deemed to be participants in the solicitation of proxies in connection with the proposed transaction. Information about CME Group's directors and executive officers is available in CME Group's proxy statement, dated March 17, 2008, for its 2008 annual meeting of stockholders. Additional information about the interests of potential participants will be included in the prospectus/proxy statement when it becomes available. This document shall not constitute an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offering of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the U.S. Securities Act of 1933, as amended.

The Globe logo, CME, Chicago Mercantile Exchange, CME Group, Globex and E- mini, are trademarks of Chicago Mercantile Exchange Inc. CBOT and Chicago Board of Trade are trademarks of the Board of Trade of the City of Chicago. All other trademarks are the property of their respective owners. Further information about CME Group and its products can be found at http://www.cmegroup.com/.

CME-G

SOURCE: CME Group Inc.

CONTACT: Media: Anita Liskey, +1-312-466-4613, or Allan Schoenberg,
+1-312-930-8189, both at news@cmegroup.com, or Investors: John Peschier,
+1-312-930-8491, all of CME Group Inc.

Web site: http://www.cme.com/
http://www.cmegroup.mediaroom.com/

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