CME GROUP INC.

20 South Wacker Drive

Chicago, Illinois 60606

(312) 930-1000

July 21, 2008

VIA EDGAR AND FACSIMILE

Mr. Duc Dang

Division of Corporation Finance

Securities and Exchange Commission

100 F. Street, N.E.

Washington, D.C. 20549-0303

 

RE:

CME Group Inc.

Registration Statement on Form S-4 (File No. 333-151577)

Dear Mr. Dang:

Pursuant to Rule 461 of the Securities Act of 1933, as amended, CME Group Inc. (the “Registrant”), respectfully requests that the effective date of the Registration Statement on Form S-4 (File No. 333-151577) filed by the Registrant on July 21, 2008, be accelerated by the Securities and Exchange Commission (the “Commission”) to July 21, 2008 at 12:00 p.m., Eastern Time, or as soon as practicable thereafter.

The Registrant hereby acknowledges that:

 

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should the Commission or the staff, acting pursuant to delegated authority, declare the filing effective, it does not foreclose the Commission from taking any action with respect to the filing;

 

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the action of the Commission or the staff, acting pursuant to delegated authority, in declaring the filing effective, does not relieve the Registrant from its full responsibility for the adequacy and accuracy of the disclosure in the filing; and

 

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the Registrant may not assert staff comments and the declaration of effectiveness as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

The Registrant respectfully requests that it be notified of such effectiveness by a telephone call to Susan S. Hassan of Skadden, Arps, Slate, Meagher & Flom LLP at (312) 407-0527 and that such effectiveness also be confirmed in writing.