Item 1.01 Entry into a Material Definitive Agreement.

On November 17, 2008, CME Group Inc., (the "Company") entered into an amendment (the "Amendment") to that certain 364 Day Revolving Credit Agreement (the "Bridge Facility") with Bank of America, N.A., in its capacity as administrative agent, and the lenders party thereto. The Bridge Facility was previously filed as an exhibit to the Company's Current Report on Form 8-K filed with the Securities and Exchange Commission on August 28, 2008. Pursuant to the terms of the Amendment, Lloyds TSB Bank plc and Barclays Bank PLC were added as additional lenders under the facility. Additionally, the Amendment provides for the postponement of the payment by the Company of certain continuation fees as described in revised Section 2.10(b).

A copy of the Amendment is attached to this report as Exhibit 10.1 and is incorporated herein by reference as though it were fully set forth herein. The description above is only a summary of the terms of the Amendment and is qualified in its entirety by the complete text of the Amendment itself.

Item 9.01 Financial Statements and Exhibits.

Amendment No. 1 to 364 Day Revolving Credit Agreement, dated as of November 17, 2008, by and among CME Group Inc., the Lenders party thereto, and Bank of America, N.A., as Administrative Agent

---

Top of the Form