UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): September 14, 2014

GFI Group Inc.

(Exact name of registrant as specified in its charter)

(212) 968-4100

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

x  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01  Other Events.

On September 15, 2014, GFI Group Inc. (the “Company”) issued a press release (the “Press Release”) announcing its response to an unsolicited proposal from BGC Partners, Inc. to acquire all of the shares of common stock of the Company for $5.25 per share in cash.  A copy of the Press Release is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated by reference herein.

Cautionary Statement Regarding Forward-Looking Statements

Certain matters discussed in this Current Report on Form 8-K and the exhibits incorporated herein contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to (i) plans, objectives, expectations and intentions; (ii) other statements contained in this communication that are not historical facts; and (iii) other statements identified by words such as “anticipate,” “believe,” “estimate,” “may,” “might,” “intend,” “expect” and similar expressions. Actual results, performance or achievements could differ materially from those contemplated, expressed or implied by the forward-looking statements contained herein. These forward-looking statements are based largely on the expectations of the Company and are subject to a number of risks and uncertainties. These include, but are not limited to, risks and uncertainties associated with: the occurrence of any event, change or other circumstances that could give rise to the termination of the definitive agreements involving the Company and CME Group Inc. (“CME”); the inability to complete the transactions contemplated by the definitive agreements involving the Company and CME due to the failure to obtain the required stockholder approval; the inability to satisfy the other conditions specified in the definitive agreements involving the Company and CME, including without limitation the receipt of necessary governmental or regulatory approvals required to complete the transactions involving the Company and CME; the risk that the proposed transactions involving the Company and CME disrupt current plans and operations, increase operating costs and the potential difficulties in customer loss and employee retention as a result of the announcement and consummation of the transactions involving the Company and CME; the outcome of any legal proceedings that may be instituted against the Company, CME or others following announcement of the transactions involving the Company and CME; economic, political and market factors affecting trading volumes; securities prices or demand for the Company’s brokerage services; competition from current and new competitors; the Company’s ability to attract and retain key personnel, including highly-qualified brokerage personnel; the Company’s ability to identify and develop new products and markets; changes in laws and regulations governing the Company’s business and operations or permissible activities; the Company’s ability to manage its international operations; financial difficulties experienced by the Company’s customers or key participants in the markets in which the Company focuses its services; the Company’s ability to keep up with technological changes; and uncertainties relating to litigation and the Company’s ability to assess and integrate acquisition prospects. Further information about factors that could affect the financial and other results of the Company are included in its filings with the Securities and Exchange Commission (“SEC”). The Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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These forward-looking statements speak only as of the date hereof. Except for the ongoing obligations of the Company to disclose material information under the federal securities laws, the Company undertakes no obligation to revise or update publicly any forward-looking statement, except as required by law. Other factors that may impact the forward-looking statements are described in the Company’s annual report on Form 10-K for the fiscal year ended December 31, 2013 and Forms 10-Q. For additional information on the Company, please visit the Company’s website at www.gfigroup.com.

Additional Information and Where to Find It

In connection with the proposed transaction between the Company and CME, the Company and CME will file relevant materials with the SEC, including a CME registration statement on Form S-4 that will include a proxy statement of the Company that also constitutes a prospectus of CME, and a definitive proxy statement/prospectus will be mailed to shareholders of the Company. INVESTORS AND SECURITY HOLDERS OF THE COMPANY ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS THAT WILL BE FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION. Investors and security holders will be able to obtain free copies of the registration statement and the proxy statement/prospectus (when available) and other documents filed with the SEC by CME and the Company, through the website maintained by the SEC at http://www.sec.gov or at the SEC public reference room at 100 F Street N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at (800) 732-0330 or visit the SEC’s website for further information on its public reference room. Copies of the documents filed with the SEC by the Company will be available free of charge on the Company’s website at http://www.gfigroup.com/ or by contacting the Company’s Investor Relations Department at (212) 968-4167. Copies of the documents filed with the SEC by CME will be available free of charge on CME’s website at http://www.cmegroup.com/ or by contacting CME’s Investor Relations Department at (312) 930-8491.

The Company and its directors, executive officers and certain of its employees may be considered participants in the solicitation of proxies in connection with the proposed transactions involving the Company and CME. Investors and security holders may obtain more detailed information regarding the names, affiliates and interests of the Company’s directors and executive officers by reading the Company’s Annual Report on Form 10-K for the year ended December 31, 2013, which was filed with the SEC on March 13, 2014, its proxy statement for its 2014 annual meeting of stockholders, which was filed with the SEC on April 22, 2014, and its Current Reports on Form 8-K filed with the SEC on February 14, 2013 and June 10, 2013. These documents can be obtained free of charge from the sources indicated above. Additional information regarding the participants in the proxy solicitations and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC when they become available. This Current Report on Form 8-K 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 appropriate registration or qualification under the securities laws of such jurisdiction. No offering of securities shall be

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made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended.

Item 9.01. Financial Statements and Exhibits

(d) Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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