CME GROUP INC. $750,000,000 5.75% Notes due 2014 UNDERWRITING AGREEMENT

Exhibit 1.1

Execution Version

CME GROUP INC.

$750,000,000 5.75% Notes due 2014

UNDERWRITING AGREEMENT

February 4, 2009

Underwriting Agreement

February 4, 0000

Xxxx xx Xxxxxxx Securities LLC

UBS Securities LLC

Barclays Capital Inc.

Lloyds TSB Bank plc

As Representatives of the several Underwriters

    c/o Banc of America Securities LLC

    Bank of America Tower

    Xxx Xxxxxx Xxxx

    Xxx Xxxx, Xxx Xxxx 00000

Ladies and Gentlemen:

CME Group Inc., a Delaware corporation (the “Company”), proposes to sell to the several Underwriters named in Schedule I hereto (the “Underwriters,” which term shall also include any underwriters substituted as hereinafter provided in Section 10 hereof), acting severally and not jointly, the respective amounts set forth in such Schedule I of $750,000,000 aggregate principal amount of the Company’s 5.75% Notes due 2014 (the “Notes”). Banc of America Securities LLC, UBS Securities LLC, Barclays Capital Inc. and Lloyds TSB Bank plc shall act as representatives (the “Representatives”) of the several Underwriters.

The Notes will be issued pursuant to an indenture, dated as of August 12, 2008 (the “Base Indenture”), between the Company and U.S. Bank National Association, as trustee (the “Trustee”). Certain terms of the Notes will be established pursuant to a supplemental indenture to the Base Indenture (together with the Base Indenture, the “Indenture”). The Notes will be issued in book-entry form in the name of Cede & Co., as nominee of The Depository Trust Company (the “Depositary”), pursuant to a Letter of Representations, to be dated on or before the Closing Date (as defined in Section 4 below), among the Company, the Trustee and the Depositary.

The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-3 (File No. 333-132554), which contains a base prospectus (the “Base Prospectus”), to be used in connection with the public offering and sale of debt securities, including the Notes, and other securities of the Company under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), and the offering thereof from time to time in accordance with Rule 415 under the Securities Act. Such registration statement, including the financial statements, exhibits and schedules thereto, in the form in which it became effective under the Securities Act, including any required information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430B under the Securities Act, is called the “Registration Statement.” The term “Prospectus” shall mean the final prospectus supplement relating to the Notes, together with

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the Base Prospectus, that is first filed pursuant to Rule 424(b) after the date and time that this Agreement is executed (the “Execution Time”) by the parties hereto. The term “Preliminary Prospectus” shall mean any preliminary prospectus supplement relating to the Notes, together with the Base Prospectus, that is first filed with the Commission pursuant to Rule 424(b). Any reference herein to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents that are or are deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act prior to 4:40 p.m., New York City time, on February 4, 2009 (the “Initial Sale Time”). All references in this Agreement to the Registration Statement, the Preliminary Prospectus, the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“XXXXX”).

All references in this Agreement to financial statements and schedules and other information which is “contained,” “included” or “stated” (or other references of like import) in the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus or the Prospectus, as the case may be, prior to the Initial Sale Time; and all references in this Agreement to amendments or supplements to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to include the filing of any document under the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), which is or is deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus or the Prospectus, as the case may be, after the Initial Sale Time.

1. Representations and Warranties of the Company. The Company represents and warrants to and agrees with each of the Underwriters as of the date hereof, as of the Initial Sale Time and as of the Closing Date (in each case, a “Representation Date”) that:

(a) The Company meets the requirements for use of Form S-3 under the Securities Act. The Registration Statement has become effective; no stop order suspending the effectiveness of the Registration Statement is in effect, and no proceedings for such purpose are pending before or, to the knowledge of the Company, threatened by the Commission.

As of the respective times the Registration Statement and any post-effective amendments thereto (including the filing with the Commission of the Company’s Annual Report on Form 10-K for the year ended December 31, 2007 (the “Annual Report on Form 10-K”)) became effective and as of each Representation Date, the Registration Statement and any amendments thereto (i) complied and will comply in all material respects with the requirements of the Securities Act and the Trust Indenture Act of 1939, as amended, and the rules and regulations promulgated thereunder (collectively, the “Trust Indenture Act”), and (ii) did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. As of the date of the Prospectus and as of the Closing Date, neither the Prospectus nor any amendments or supplements thereto included or will include an untrue statement of a material fact or omitted or will omit to state a

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material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. Notwithstanding the foregoing, the representations and warranties in this subsection shall not apply to statements in or omissions from the Registration Statement or any post-effective amendment or the Prospectus or any amendments or supplements thereto made in reliance upon and in conformity with information furnished to the Company in writing by any of the Underwriters through the Representatives expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter through the Representatives consists of the information described as such in Section 8(b) hereof.

Each Preliminary Prospectus and the Prospectus, as of the time each was filed with the SEC, complied in all material respects with the Securities Act, and the Preliminary Prospectus and the Prospectus delivered to the Underwriters for use in connection with the offering of the Notes will, as of the time of such delivery, be identical to any electronically transmitted copies thereof filed with the Commission pursuant to XXXXX, except to the extent permitted by Regulation S-T.

(b) The term “Disclosure Package” shall mean (i) the Preliminary Prospectus dated February 4, 2009, (ii) the issuer free writing prospectuses as defined in Rule 433 of the Securities Act (each, an “Issuer Free Writing Prospectus”), if any, identified in Schedule II hereto and (iii) any other free writing prospectus that the parties hereto shall hereafter expressly agree in writing to treat as part of the Disclosure Package. As of the Initial Sale Time, (i) the Disclosure Package and (ii) each electronic road show, when taken together as a whole with the Disclosure Package, did not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from the Disclosure Package based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter through the Representatives consists of the information described as such in Section 8(b) hereof.

(c) The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus (i) as of the time they were or hereafter are filed with the Commission, complied or will comply in all material respects with the requirements of the Exchange Act and (ii) when read together with the other information in the Disclosure Package, as of the Initial Sale Time, and when read together with the other information in the Prospectus, as of the date of the Prospectus and as of the Closing Date, did not or will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(d) (i) As of the time of filing the Registration Statement, (ii) as of the time of the most recent amendment thereto for the purposes of complying with Section 10(a)(3) of the Securities Act (whether such amendment was by post-effective amendment, incorporated report filed pursuant to Section 13 or 15(d) of the Exchange Act or form of prospectus), (iii) as of the time the Company or any person acting on its behalf (within the meaning, for this clause only, of Rule 163(c) of the Securities Act) made any offer

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relating to the Notes in reliance on the exemption of Rule 163 of the Securities Act and (iv) as of the Execution Time, the Company was and is a “well known seasoned issuer” as defined in Rule 405 of the Securities Act. The Registration Statement is an “automatic shelf registration statement,” as defined in Rule 405 of the Securities Act, that automatically became effective not more than three years prior to the Execution Time; the Company has not received from the Commission any notice pursuant to Rule 401(g)(2) of the Securities Act objecting to use of the automatic shelf registration statement form and the Company has not otherwise ceased to be eligible to use the automatic shelf registration form.

(e) (i) As of the time of filing the Registration Statement and (ii) as of the Execution Time (with such date being used as the determination date for purposes of this clause (ii)), the Company was not and is not an Ineligible Issuer (as defined in Rule 405 of the Securities Act), without taking account of any determination by the Commission pursuant to Rule 405 of the Securities Act that it is not necessary that the Company be considered an Ineligible Issuer.

(f) Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the offering of Notes under this Agreement or until any earlier date that the Company notified or notifies the Representatives as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained, or incorporated by reference, in the Registration Statement, the Preliminary Prospectus or the Prospectus. If at any time following issuance of an Issuer Free Writing Prospectus there occurs an event or development as a result of which such Issuer Free Writing Prospectus would conflict with the information contained, or incorporated by reference, in the Registration Statement, the Preliminary Prospectus or the Prospectus, the Company will promptly notify the Representatives and will promptly amend or supplement, at its own expense, such Issuer Free Writing Prospectus to eliminate or correct such conflict. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter through the Representatives consists of the information described as such in Section 8(b) hereof.

(g) The Company has not distributed any offering material in connection with the offering and sale of the Notes other than the Preliminary Prospectus, the Prospectus and any Issuer Free Writing Prospectus reviewed and consented to by the Representatives and included in Schedule II hereto or the Registration Statement.

(h) The Company has been duly incorporated, is validly existing as a corporation in good standing under the laws of the State of Delaware, has the corporate power and authority to own its property and to conduct its business as described in the Disclosure Package and the Prospectus and is duly qualified to transact business and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property requires such qualification, except to the extent that the failure to be so qualified or be in good standing would not have a material adverse effect on the Company and its subsidiaries, taken as a whole (a “Material Adverse Effect”); all of the issued shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable.

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(i) Each “significant subsidiary” of the Company (as such term is defined in Rule 1-02 of Regulation S-X) (each, a “Subsidiary” and together, the “Subsidiaries”) has been duly incorporated, is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation to the extent such concept is applicable in such jurisdiction, has the corporate power and authority to own its property and to conduct its business as described in the Disclosure Package and the Prospectus and is duly qualified to transact business and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property requires such qualification, except to the extent that the failure to be so qualified or be in good standing would not have a Material Adverse Effect; all of the issued shares of capital stock of each Subsidiary have been duly authorized and validly issued, are fully paid and non-assessable and are directly owned by the Company, free and clear of any security interest, mortgage, pledge, lien encumbrance or claim. The Company’s sole “significant subsidiaries” are Board of Trade of the City of Chicago, Inc. and Chicago Mercantile Exchange Inc.

(j) This Agreement has been duly authorized, executed and delivered by the Company.

(k) The authorized capital stock of the Company conforms as to legal matters to the description thereof contained in the Disclosure Package and the Prospectus.

(l) The Indenture has been duly authorized by the Company and duly qualified under the Trust Indenture Act and, when duly executed and delivered by the Company and the Trustee, will constitute a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms, except as the enforcement thereof may be limited by bankruptcy, insolvency, fraudulent conveyance or transfer, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles (regardless of whether such enforceability is considered in a proceeding at law or in equity).

(m) The Notes to be purchased by the Underwriters from the Company have been duly authorized for issuance and sale pursuant to this Agreement and the Indenture and, as of the Closing Date, will have been duly executed by the Company and, when authenticated in the manner provided for in the Indenture and issued and delivered against payment of the purchase price therefor, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their terms, except as the enforcement thereof may be limited by bankruptcy, insolvency, fraudulent conveyance or transfer, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles (regardless of whether such enforceability is considered in a proceeding at law or in equity), and will be in the form contemplated by, and entitled to the benefits of, the Indenture.

(n) The Notes, upon issuance, and the Indenture, upon execution, will conform in all material respects to the descriptions thereof contained in the Disclosure Package and the Prospectus.

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(o) The statements in the Annual Report on Form 10-K under the caption “Regulatory Matters,” in each case insofar as such statements constitute a summary of certain provisions of specific agreements, statutes or regulations referred to therein, fairly present and summarize, in all material respects, such provisions referred to therein (it being understood that the Company makes no representation or warranty with respect to the status of any legislative matters).

(p) The execution and delivery by the Company of, and the performance by the Company of its obligations under, this Agreement and the issuance and sale of the Notes and compliance by the Company with the terms thereof (x) have been duly authorized by all necessary corporate action, (y) will not contravene (i) any provision of applicable law, (ii) the certificate of incorporation or by-laws of the Company or any of its Subsidiaries, (iii) any indenture, mortgage, deed of trust, credit agreement, lease or other agreement or instrument binding upon the Company or any of its Subsidiaries that is material to the Company and its Subsidiaries, taken as a whole, or (iv) any judgment, order or decree of any governmental body, agency or court having jurisdiction over the Company or any of its Subsidiaries, except for any breach or contravention described in clause (i), (iii) or (iv) which would not, singly or in the aggregate, have a Material Adverse Effect or will not materially and adversely affect the Company’s ability to perform its obligations under this Agreement, the Indenture and the Notes or consummate the transactions contemplated hereby and thereby and (z) will not constitute a Debt Repayment Triggering Event (as defined below) under any indenture, mortgage, deed of trust, credit agreement, lease or other agreement or instrument binding upon the Company (except for such Debt Repayment Triggering Events that would not result in a Material Adverse Effect or will not materially and adversely affect the ability of the Company to perform its obligations under this Agreement, the Indenture or the Notes or consummate the transactions contemplated hereby and thereby); and no consent, approval, authorization or order of, or qualification with, any governmental body or agency, including but not limited to the Commodity Futures Trading Commission, is required for the performance by the Company of its obligations under this Agreement, except such as may be required by the securities or blue sky laws of the various states, or any applicable law, rule or regulation of any foreign jurisdiction in connection with the offer and sale of the Notes and except, in each case, as would not singly or in the aggregate have a Material Adverse Effect. As used herein, a “Debt Repayment Triggering Event” means any event or condition which gives, or with the giving of notice or lapse of time or both would give, the holder of any note, debenture or other evidence of indebtedness (or any person acting on such holder’s behalf) issued by the Company, the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its Subsidiaries.

(q) Since the respective dates as of which information is given in the Registration Statement, the Disclosure Package or the Prospectus, except as otherwise stated therein, (A) there has not occurred any change in the capital stock or long-term debt of the Company or any of its Subsidiaries, or any material adverse change, or any development reasonably likely to result in a prospective material adverse change, in the condition, financial or otherwise, or in the earnings, business or operations of the Company and its Subsidiaries, taken as a whole (a “Material Adverse Change”), (B) there have been no transactions entered into by the Company or any of its subsidiaries, other than those in the ordinary course of business, which are material with respect to the Company and its subsidiaries considered as one enterprise and (C) except for regularly quarterly dividends on the common stock of the Company, there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock.

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(r) There are no legal or governmental proceedings pending or, to the knowledge of the Company, threatened to which the Company or any of its Subsidiaries is a party or to which any of the properties of the Company or any of its Subsidiaries is subject that are required to be disclosed in the Registration Statement, the Disclosure Package or the Prospectus that are not so disclosed.

(s) The Company is not and, after giving effect to the offering and sale of the Notes and the use of the proceeds therefrom as described in the Preliminary Prospectus and the Prospectus will not be, an “investment company” subject to registration and regulation, as such term is defined in the Investment Company Act of 1940, as amended.

(t) The Company and its Subsidiaries have good and marketable title to all real property owned by them, free and clear of all liens, encumbrances and defects except such as are described in the Disclosure Package and the Prospectus or such as would not have a Material Adverse Effect; and any real property and buildings held under lease by the Company and its Subsidiaries are held by them under valid, subsisting and enforceable leases with such exceptions as are described in the Disclosure Package and the Prospectus or as would not have Material Adverse Effect.

(u) The Company and its Subsidiaries own or possess, or can acquire on reasonable terms, all material patents, patent rights, licenses, inventions, copyrights, know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), trademarks, service marks and trade names currently employed by them in connection with the business now operated by them except where the failure to so own or possess would not, singly or in the aggregate, result in a Material Adverse Effect, and, except as described in the Disclosure Package and the Prospectus, neither the Company nor any of its Subsidiaries has received any notice of infringement of or conflict with asserted rights of others with respect to any of the foregoing which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a Material Adverse Effect.

(v) No labor dispute with the employees of the Company or any of its Subsidiaries exists, except as described in the Disclosure Package and the Prospectus, or, to the knowledge of the Company, is imminent, except such disputes that would not have a Material Adverse Effect.

(w) The Company and each of its Subsidiaries has all necessary consents, licenses, authorizations, approvals, exemptions, orders, certificates and permits (collectively, the “Consents”) of and from, and has made all filings and declarations (collectively, the “Filings”) with, all federal, state, local and foreign governmental and regulatory authorities, all self-regulatory organizations and all courts and other tribunals, necessary to own, lease, license and use its properties and assets and to conduct its business in the manner described in the Disclosure Package and the Prospectus, except where the failure to have such Consents or to make such Filings would not, individually or in the aggregate, have a Material Adverse Effect; all such Consents and Filings are in full force and effect,

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the Company and its Subsidiaries are in compliance with such Consents and neither the Company nor any of its Subsidiaries has received any notice of any inquiry, investigation or proceeding that would reasonably be expected to result in the suspension, revocation or limitation of any such Consent or otherwise impose any limitation on the conduct of the business of the Company or any of its Subsidiaries, except as set forth in the Disclosure Package and the Prospectus or any such failure to be in full force and effect, failure to be in compliance with, suspension, revocation or limitation which would not, singly or in the aggregate, have a Material Adverse Effect; the Company and its Subsidiaries are in compliance with, and conduct their businesses in conformity with, all applicable laws and regulations, except where the failure to so comply or conform would not have a Material Adverse Effect.

(x) Neither the Company nor any of its Subsidiaries is (i) in violation of its certificate of incorporation or by-laws or (ii) in default in any material respect, and no event has occurred which, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, credit agreement or other agreement or instrument to which it is a party or by which it is bound or to which any of its property or assets is subject, except for any default described in clause (ii) which would not have a Material Adverse Effect.

(y) The Company and each of its Subsidiaries have filed all federal, state, local and foreign tax returns required to be filed through the date of this Agreement or has requested extensions thereof (except for cases in which the failure to file would not have a Material Adverse Effect) and have paid all taxes required to be paid thereon, and, except as currently being contested in good faith and for which reserves required by generally accepted accounting principles as applied in the United States (“GAAP”) have been created on the financial statements of the Company, no tax deficiency has been determined adversely to the Company or any of its Subsidiaries which has had a Material Adverse Effect.

(z) The Company maintains disclosure controls and procedures that are designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the Commission’s rules and forms, and is accumulated and communicated to the Company’s management, including its principal executive officer or officers and principal financial officer or officers, as appropriate to allow timely decisions regarding disclosure.

(aa) The Company maintains, on a consolidated basis, an effective system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain asset accountability, (iii) access to assets is permitted only in accordance with management’s general or specific authorization and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences.

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(bb) Except as disclosed in the Disclosure Package and the Prospectus, since the end of the Company’s most recent audited fiscal year, there has been (i) no material weakness in the Company’s internal control over financial reporting (whether or not remediated) and (ii) no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting.

(cc) The Company has not taken and will not take, directly or indirectly, any action which is designed to or which has constituted or which might reasonably be expected to cause or result in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Notes.

(dd) Ernst & Young LLP, who have certified certain financial statements of the Company and its subsidiaries, are independent public accountants as required by the Securities Act, the Exchange Act and the rules and regulations of the Commission thereunder and are an independent registered public accounting firm with the Public Company Accounting Oversight Board.

(ee) To the knowledge of the Company, KPMG LLP, who have certified certain financial statements of NYMEX Holdings, Inc. and its subsidiaries, were independent public accountants with respect to NYMEX Holdings, Inc. and its subsidiaries as of June 30, 2008, as required by the Securities Act, the Exchange Act and the rules and regulations of the Commission thereunder and are an independent registered public accounting firm with the Public Company Accounting Oversight Board.

(ff) The financial statements of the Company together with the related notes thereto incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus present fairly, in all material respects, the consolidated financial position of the Company and its subsidiaries as of and at the dates indicated and the results of their operations and cash flows for the periods specified. Such financial statements comply as to form with the accounting requirements of the Securities Act and have been prepared in conformity with GAAP applied on a consistent basis throughout the periods involved, except as may be expressly stated in the related notes thereto. The selected financial data and the summary financial information included in the Preliminary Prospectus and the Prospectus present fairly, in all material respects, the information shown therein and have been compiled on a basis consistent with that of the audited financial statements incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus. In addition, the pro forma financial statements of the Company and its subsidiaries and the related notes thereto that are incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus present fairly, in all material respects, the information shown therein, have been prepared in accordance with the Commission’s rules and guidelines with respect to pro forma financial statements, if applicable, and have been appropriately compiled on the bases described therein, and the assumptions used in the preparation thereof are reasonable and the adjustments used therein are appropriate to give effect to the transactions and circumstances referred to therein.

(gg) None of the Company, any of its Subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its Subsidiaries is aware of or has taken any action, directly or indirectly, that would

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result in a violation by such persons of the FCPA, including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA, and the Company, its Subsidiaries and, to the knowledge of the Company, its affiliates have conducted their businesses in compliance in all material respects with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

“FCPA” means Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder.

(hh) The operations of the Company and its Subsidiaries are in compliance in all material respects with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all applicable jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its Subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(ii) Neither the Company nor any of its Subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its Subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”); and the Company will not knowingly, directly or indirectly, use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds, to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(jj) To the knowledge of the Company without having conducted any independent audit, the representations and warranties contained in paragraph (ff) of this Section 1 are true and correct with respect to the financial statements and any supporting schedules of NYMEX Holdings, Inc. and its consolidated subsidiaries, included or incorporated by reference in the Registration Statement, the Disclosure Package and the Prospectus; except where the failure to be so true and correct would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(kk) There are no contracts or documents which are required to be described in the Registration Statement, the Preliminary Prospectus, the Prospectus or the documents incorporated by reference therein or to be filed as exhibits to the Registration Statement which have not been so described or filed, as the case may be.

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2. Agreements to Sell and Purchase. The Company hereby agrees to issue and sell to the several Underwriters, and each Underwriter, upon the basis of the representations and warranties herein contained, but subject to the conditions hereinafter stated, agrees, severally and not jointly, to purchase from the Company the aggregate principal amount of Notes set forth opposite their names on Schedule I, plus any additional principal amount of Notes that such Underwriter may become obligated to purchase pursuant to the provisions of Section 10 hereof, at a purchase price of 99.384% of the principal amount of the Notes (the “Purchase Price”), payable on the Closing Date. The Company will not be obligated to deliver any of the Notes except upon payment for all the Notes to be purchased as provided herein.

3. Terms of Public Offering. The Company is advised by the Representatives that the Underwriters propose to make a public offering of their respective portions of the Notes, as described in the Disclosure Package and the Prospectus, as soon after the Execution Time as in the Representatives’ judgment is advisable. The Company is further advised by the Representatives that the Notes are to be offered to the public initially at 99.839% of the principal amount of the Notes (the “Public Offering Price”) and to certain dealers selected by the Representatives at a price that represents a concession not in excess of 0.275% of the principal amount of the Notes.

4. Payment and Delivery. Payment for the Notes to be sold by the Company shall be made to the Company by wire transfer of immediately available funds to a bank account designated by the Company against delivery of such Notes for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on February 9, 2009 (unless postponed in accordance with the provisions of Section 10 hereof), or at such other time on the same or such other date, not later than February 16, 2009, as shall be designated in writing by the Representatives, at the offices of Xxxxxx Xxxxxxxx Xxxxx & Xxxxxxxx LLP, Xxx Xxxxxxx Xxxxx, Xxx Xxxx, Xxx Xxxx 00000. The time and date of such payment are hereinafter referred to as the “Closing Date.”

The Notes shall be registered in such names and such denominations ($2,000 and integral multiples of $1,000 in excess thereof) as the Representatives shall request in writing not later than one full business day prior to the Closing Date. The Notes shall be delivered to the Representatives on the Closing Date for the respective accounts of the several Underwriters, unless the Representatives shall otherwise instruct, with any transfer taxes payable in connection with the transfer of the Notes to the Underwriters duly paid by the Company, against payment of the Purchase Price therefor.

5. Conditions to the Underwriters’ Obligations. The obligations of the several Underwriters to purchase and pay for the Notes as provided herein on the Closing Date shall be subject to the accuracy of the representations and warranties on the part of the Company set forth in Section 1 hereof as of each Representation Date as though then made and to the timely performance by the Company of its covenants and other obligations hereunder, and to each of the following additional conditions:

(a) The Registration Statement shall be effective under the Securities Act and no stop order suspending the effectiveness of the Registration Statement shall have been issued under the Securities Act and no proceedings for that purpose shall have been instituted or be pending or threatened by the Commission, any request on the part of the Commission for additional information shall

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have been complied with to the reasonable satisfaction of counsel to the Underwriters and the Company shall not have received from the Commission any notice pursuant to Rule 401(g)(2) of the Securities Act objecting to use of the automatic shelf registration statement form. The Preliminary Prospectus and the Prospectus shall have been filed with the Commission in accordance with Rule 424(b) (or a post-effective amendment providing such information shall have been filed and become effective in accordance with the requirements of Rule 430B).

(b) Subsequent to the execution and delivery of this Agreement and prior to the Closing Date:

(i) there shall not have occurred any downgrading in the rating accorded to the Notes or any of the Company’s other debt securities by any “nationally recognized statistical rating organization,” as such term is defined for purposes of Rule 436(g)(2) under the Securities Act and no such organization shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of the Notes or any of the Company’s other debt securities; and

(ii) there shall not have occurred or be existing any Material Adverse Change which is not described in the Disclosure Package and the Prospectus (exclusive of any amendments or supplements thereto subsequent to the date of this Agreement) that makes it, in the Representatives’ judgment, impracticable to proceed with the offering, sale or delivery of the Notes on the terms and in the manner contemplated in the Disclosure Package and the Prospectus.

(c) The Underwriters shall have received on the Closing Date a certificate, dated the Closing Date and signed by the Chairman of the Board or the Chief Executive Officer or the President or a Managing Director of the Company and the Chief Financial Officer or Chief Accounting Officer of the Company, (i) to the effect set forth in Section 5(b)(i) above, (ii) confirming that, to the knowledge of such officer, the representations and warranties of the Company in Sections 1(a) and 1(b) hereof are true and correct, (iii) confirming that the other representations and warranties of the Company contained in this Agreement are true and correct as of the Closing Date, (iv) confirming that no stop order suspending the effectiveness of the Registration Statement has been received by the Company and no proceedings for that purpose have been instituted or, to the Company’s knowledge, threatened, (v) confirming that the Company has not received from the Commission any notice pursuant to Rule 401(g)(2) of the Securities Act objecting to the use of the automatic shelf registration statement form and (vi) confirming that the Company has complied with all of the agreements and satisfied all of the conditions on its part to be performed or satisfied hereunder on or before the Closing Date.

The officers signing and delivering such certificate may rely upon the best of their knowledge as to proceedings threatened.

(d) The Underwriters shall have received on the Closing Date an opinion of Skadden, Arps, Slate, Xxxxxxx & Xxxx LLP, outside counsel for the Company, dated the Closing Date, to the effect set forth on Exhibit A and otherwise in form and substance satisfactory to the Representatives.

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(e) The Underwriters shall have received on the Closing Date an opinion of Xxxxxxxx X. Xxxxxx, Managing Director, General Counsel and Corporate Secretary of the Company, dated the Closing Date, to the effect set forth on Exhibit B and otherwise in form and substance satisfactory to the Representatives.

(f) The Underwriters shall have received on the Closing Date an opinion of Xxxxxx Xxxxxxxx Xxxxx & Xxxxxxxx LLP, counsel for the Underwriters, dated the Closing Date, with respect to such matters as may be reasonably requested by the Representatives.

(g) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance reasonably satisfactory to the Representatives, from Ernst & Young LLP, independent public accountants, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in or incorporated by reference into the Registration Statement, the Disclosure Package and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off date” not earlier than the date hereof.

(h) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance reasonably satisfactory to the Representatives, from KPMG LLP, independent public accountants, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in or incorporated by reference into the Registration Statement, the Disclosure Package and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off date” not earlier than the date hereof.

(i) Prior to the Closing Date, the Company shall have furnished to the Representatives such further certificates and documents as the Representatives may reasonably request.

6. Covenants of the Company. In further consideration of the agreements of the Underwriters herein contained, the Company covenants with each Underwriter as follows:

(a) The Company, subject to Section 6(b), will comply with the requirements of Rule 430B of the Securities Act, and will promptly notify the Representatives, and confirm the notice in writing, of (i) the effectiveness during the Prospectus Delivery Period (as defined below) of any post-effective amendment to the Registration Statement or the filing of any supplement or amendment to the Prospectus, (ii) the receipt of any comments from the Commission during the Prospectus Delivery Period, (iii) any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or for additional information, and (iv) the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any order preventing or suspending the use of the Preliminary Prospectus or the Prospectus, or of the suspension of the qualification of the Notes for offering or sale in any jurisdiction, or of the initiation or threatening of any proceedings for any of such

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purposes. The Company will promptly effect the filings necessary pursuant to Rule 424 and will take such steps as it deems necessary to ascertain promptly whether the form of the Preliminary Prospectus and the Prospectus transmitted for filing under Rule 424 was received for filing by the Commission and, in the event that it was not, it will promptly file such document. The Company will use its reasonable efforts to prevent the issuance of any stop order and, if any stop order is issued, to obtain the lifting thereof at the earliest possible moment.

(b) During such period beginning on the date of this Agreement and ending on the later of the Closing Date or such date as, in the opinion of counsel for the Underwriters, the Prospectus is no longer required by law to be delivered in connection with sales of the Notes by an Underwriter or dealer, including in circumstances where such requirement may be satisfied pursuant to Rule 172 of the Securities Act (the “Prospectus Delivery Period”), the Company will give the Representatives notice of its intention to file or prepare any amendment to the Registration Statement (including any filing under Rule 462(b) of the Securities Act), or any amendment, supplement or revision to the Disclosure Package or the Prospectus, whether pursuant to the Securities Act, the Exchange Act or otherwise, will furnish the Representatives with copies of any such documents a reasonable amount of time prior to such proposed filing or use, as the case may be, and will not file or use any such document to which the Representatives or counsel for the Underwriters shall reasonably object.

(c) The Company has furnished or will deliver, upon request, to the Representatives and counsel for the Underwriters, without charge, signed copies of the Registration Statement as originally filed and of each amendment thereto (including exhibits filed therewith or incorporated by reference therein and documents incorporated or deemed to be incorporated by reference therein) and signed copies of all consents and certificates of experts, and will also deliver to the Representatives, without charge, a conformed copy of the Registration Statement as originally filed and of each amendment thereto (without exhibits) for each of the Underwriters. The Registration Statement and each amendment thereto furnished to the Underwriters will be identical to any electronically transmitted copies thereof filed with the Commission pursuant to XXXXX, except to the extent permitted by Regulation S-T.

(d) The Company will deliver to each Underwriter, without charge, as many copies of the Preliminary Prospectus as such Underwriter may reasonably request, and the Company hereby consents to the use of such copies for purposes permitted by the Securities Act. The Company will furnish to each Underwriter, without charge, during the Prospectus Delivery Period, such number of copies of the Prospectus as such Underwriter may reasonably request. The Preliminary Prospectus and the Prospectus and any amendments or supplements thereto furnished to the Underwriters will be identical to any electronically transmitted copies thereof filed with the Commission pursuant to XXXXX, except to the extent permitted by Regulation S-T.

(e) The Company will comply with the Securities Act and the Exchange Act so as to permit the completion of the distribution of the Notes as contemplated in this Agreement and in the Registration Statement, the Disclosure Package and the Prospectus. If at any time during the Prospectus Delivery Period, any event shall occur or condition shall exist as a result of which it

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is necessary, in the opinion of counsel for the Underwriters or for the Company, to amend the Registration Statement in order that the Registration Statement will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading or to amend or supplement the Disclosure Package or the Prospectus in order that the Disclosure Package or the Prospectus, as the case may be, will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing as of the Initial Sale Time and as of the time it is delivered or conveyed to a purchaser, not misleading, or if it shall be necessary, in the opinion of either such counsel, at any such time to amend the Registration Statement or amend or supplement the Disclosure Package or the Prospectus in order to comply with the requirements of any law, the Company will (1) notify the Representatives of any such event, development or condition and (2) promptly prepare and file with the Commission, subject to Section 6(b) hereof, such amendment or supplement as may be necessary to correct such statement or omission or to make the Registration Statement, the Disclosure Package or the Prospectus comply with such law, and the Company will furnish to the Underwriters, without charge, such number of copies of such amendment or supplement as the Underwriters may reasonably request.

(f) The Company shall cooperate with the Representatives and counsel for the Underwriters to qualify or register the Notes for sale under (or obtain exemptions from the application of) the state securities or blue sky laws of those jurisdictions designated by the Representatives, shall comply with such laws and shall continue such qualifications, registrations and exemptions in effect so long as required for the distribution of the Notes. The Company shall not be required to qualify to transact business or to take any action that would subject it to general service of process in any such jurisdiction where it is not presently qualified or where it would be subject to taxation as a foreign business. The Company will advise the Representatives promptly after the Company becomes aware of the suspension of the qualification or registration of (or any such exemption relating to) the Notes for offering, sale or trading in any jurisdiction or any initiation or threat of any proceeding for any such purpose, and in the event of the issuance of any order suspending such qualification, registration or exemption, the Company shall use its reasonable best efforts to obtain the withdrawal thereof at the earliest possible moment.

(g) The Company shall apply the net proceeds from the sale of the Notes sold by it in the manner described under the caption “Use of Proceeds” in the Preliminary Prospectus and the Prospectus.

(h) The Company will cooperate with the Underwriters and use its reasonable efforts to permit the Notes to be eligible for clearance and settlement through the facilities of the Depositary.

(i) During the Prospectus Delivery Period, the Company shall file, on a timely basis, with the Commission all reports and documents required to be filed under the Exchange Act.

(j) During the period commencing on the date hereof and ending on the Closing Date, the Company will not, without the prior written consent of the Representatives sell, offer, contract or otherwise dispose of or transfer any debt securities of the Company similar to the Notes (other than as contemplated by this Agreement with respect to the Notes).

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(k) The Company will prepare a final term sheet containing only a description of the Notes, in a form approved by the Representatives and attached as Schedule III hereto, and will file such term sheet pursuant to Rule 433(d) under the Securities Act within the time required by such rule (such term sheet, the “Final Term Sheet”). The Final Term Sheet is an Issuer Free Writing Prospectus for purposes of this Agreement.

(l) The Company represents that it has not made, and agrees that, unless it obtains the prior consent of the Representatives, and each Underwriter represents and agrees that, unless it obtains the prior consent of the Company and the Representatives, it will not make, any offer relating to the Notes that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a “free writing prospectus” (as defined in Rule 405 of the Securities Act) required to be filed by the Company with the Commission or retained by the Company under Rule 433 of the Securities Act; provided that the prior consent of the Company and Representatives shall be deemed to have been given in respect of any Issuer Free Writing Prospectus included in Schedule II to this Agreement. Any such free writing prospectus consented to or deemed to be consented to by the Company and Representatives is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company agrees that (i) it has treated and will treat, as the case may be, each Permitted Free Writing Prospectus as an Issuer Free Writing Prospectus, and (ii) has complied and will comply, as the case may be, with the requirements of Rules 164 and 433 of the Securities Act applicable to any Permitted Free Writing Prospectus, including in respect of timely filing with the Commission, where required, legending and record keeping. The Company consents to the use by any Underwriter of a free writing prospectus that (a) is not an “issuer free writing prospectus” as defined in Rule 433, and (b) contains only (i) information describing the preliminary terms of the Notes or their offering, (ii) information permitted by Rule 134 under the Securities Act, (iii) information that describes the final terms of the Notes or their offering and that is included in the Final Term Sheet of the Company contemplated in Section 6(k) or (iv) information describing comparable bond prices in any Bloomberg L.P. or other electronic communication.

(m) If immediately prior to the third anniversary (the “Renewal Deadline”) of the initial effective date of the Registration Statement, any of the Notes remain unsold by the Underwriters, the Company will prior to the Renewal Deadline file, if it has not already done so and is eligible to do so, a new automatic shelf registration statement relating to the Notes, in a form satisfactory to the Representatives. If the Company is no longer eligible to file an automatic shelf registration statement, the Company will prior to the Renewal Deadline, if it has not already done so, file a new shelf registration statement relating to the Notes, in a form satisfactory to the Representatives, and will use its reasonable best efforts to cause such registration statement to be declared effective within 60 days after the Renewal Deadline. The Company will take all other action necessary or appropriate to permit the public offering and sale of the Notes to continue as contemplated in the expired registration statement relating to the Notes. References herein to the Registration Statement shall include such new automatic shelf registration statement or such new shelf registration statement, as the case may be.

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(n) If at any time during the Prospectus Delivery Period, the Company receives from the Commission a notice pursuant to Rule 401(g)(2) or otherwise ceases to be eligible to use the automatic shelf registration statement form, the Company will (i) promptly notify the Representatives, (ii) promptly file a new registration statement or post-effective amendment on the proper form relating to the Notes, in a form satisfactory to the Representatives, (iii) use its reasonable efforts to cause such registration statement of post-effective amendment to be declared effective and (iv) promptly notify the Representatives of such effectiveness. The Company will take all other action reasonably necessary or appropriate to permit the public offering and sale of the Notes to continue as contemplated in the registration statement that was the subject of the Rule 401(g)(2) notice or for which the Company has otherwise become ineligible. References herein to the Registration Statement shall include such new registration statement or post-effective amendment, as the case may be.

(o) The Company agrees to pay the required Commission filing fees relating to the Notes within the time required by and in accordance with Rule 456(b)(1) and 457(r) of the Securities Act.

(p) The Company will not take, directly or indirectly, any action designed to cause or result in, or that has constituted or might reasonably be expected to constitute, under the Exchange Act or otherwise, the stabilization or manipulation of the price of any securities of the Company to facilitate the sale or resale of the Notes.

The Representatives, on behalf of the several Underwriters, may, in their sole discretion, waive in writing the performance by the Company of any one or more of the foregoing covenants or extend the time for their performance.

7. Expenses. Whether or not the transactions contemplated in this Agreement are consummated or this Agreement is terminated, the Company agrees to pay or cause to be paid all expenses incident to the performance of its obligations under this Agreement, including: (i) the fees, disbursements and expenses of the Company’s counsel and the Company’s accountants in connection with the registration and delivery of the Notes under the Securities Act and all other fees or expenses in connection with the preparation and filing of the Registration Statement, each Issuer Free Writing Prospectus, the Preliminary Prospectus, the Prospectus and amendments and supplements to any of the foregoing, including all printing costs associated therewith, and the mailing and delivering of copies thereof to the Underwriters and dealers, in the quantities hereinabove specified; (ii) all costs and expenses related to the issuance and delivery of the Notes to the Underwriters, including any necessary issue, transfer or other stamp taxes payable thereon; (iii) the cost of printing or producing any Blue Sky or Legal Investment memorandum requested by the Representatives in connection with the offer and sale of the Notes under state securities laws and all expenses in connection with the qualification of the Notes for offer and sale under state securities laws as provided in Section 6(f) hereof, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters (not to exceed $20,000 in the aggregate) in connection with such qualification and in connection with the Blue Sky or Legal Investment memorandum; (iv) the cost of printing certificates representing the Notes; (v) the costs and charges of any transfer agent, registrar or depositary; (vi) the costs and expenses of the Company relating to investor presentations on any “road show” undertaken in connection with the marketing of the offering of the Notes, including, without limitation, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants

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engaged in connection with the road show presentations with the prior approval of the Company, travel and lodging expenses of the representatives and officers of the Company and any such consultants, and the cost of any aircraft chartered in connection with the road show; (vii) the document production charges and expenses associated with printing this Agreement; (viii) all expenses of the Company in connection with any offer and sale of the Notes outside of the United States; (ix) the fees and expenses of the Trustee, including the reasonable fees and disbursements of counsel for the Trustee in connection with the Indenture and the Notes, (x) any fees payable in connection with the rating of the Notes with the ratings agencies, (xi) all fees and expenses (including reasonable fees and expenses of counsel) of the Company in connection with approval of the Notes by the Depositary for “book-entry” transfer and (xii) all other costs and expenses incident to the performance of the obligations of the Company hereunder for which provision is not otherwise made in this Section. It is understood, however, that except as provided in this Section, Section 8 and Section 11, the Underwriters will pay all of their costs and expenses, including fees and disbursements of their counsel, issue, transfer or other stamp taxes payable on resale of any of the Notes by them and any advertising expenses connected with any offers they may make.

8. Indemnity and Contribution.

(a) The Company agrees to indemnify and hold harmless each Underwriter, each person, if any, who controls any Underwriter within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act, and each affiliate of any Underwriter within the meaning of Rule 405 under the Securities Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred by such indemnified party in connection with defending or investigating any such action or claim) arising out of or caused by any untrue statement or alleged untrue statement of a material fact contained in (x) the Registration Statement or any amendment thereof or arising out of or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, except, insofar as such losses, claims, damages or liabilities arise out of or are caused by any such untrue statement or omission or alleged untrue statement or omission based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein or (y) any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (as amended or supplemented if the Company shall have furnished any amendments or supplements thereto) or arising out of or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, except, insofar as such losses, claims, damages or liabilities arise out of or are caused by any such untrue statement or omission or alleged untrue statement or omission based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein. The indemnity agreement set forth in this Section 8(a) shall be in addition to any liabilities that the Company may otherwise have.

(b) Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, the directors and officers of the Company who signed the Registration Statement and each person, if any, who controls the Company within the

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meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred by such indemnified party in connection with defending or investigating any such action or claim) arising out of or caused by any untrue statement or alleged untrue statement of a material fact contained in (x) the Registration Statement or any amendment thereof or arising out of or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, but only with reference to information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the therein or (y) any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (as amended or supplemented if the Company shall have furnished any amendments or supplements thereto), or arising out of or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, but only with reference to information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein; it being understood and agreed that the only such information furnished to the Company by any Underwriter through the Representatives expressly for use in the Registration Statement, any Issuer Free Writing Prospectus, the Preliminary Prospectus, the Prospectus or any amendments or supplements thereto consists of the statements set forth in the fifth, ninth and tenth paragraphs of text under the caption “Underwriting” in the Preliminary Prospectus and the Prospectus and the third sentence of the eighth paragraph of text under the caption “Underwriting” in the Preliminary Prospectus and the Prospectus. The indemnity agreement set forth in this Section 8(b) shall be in addition to any liabilities that each Underwriter may otherwise have.

(c) In case any proceeding (including any governmental investigation) shall be instituted involving any person in respect of which indemnity may be sought pursuant to Section 8(a) or 8(b), such person (the “indemnified party”) shall promptly notify the person against whom such indemnity may be sought (the “indemnifying party”) in writing, and the indemnifying party, upon request of the indemnified party, shall retain counsel reasonably satisfactory to the indemnified party to represent the indemnified party and any others the indemnifying party may designate in such proceeding and shall pay the reasonable fees and disbursements of such counsel related to such proceeding. In any such proceeding, any indemnified party shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such indemnified party unless (i) the indemnifying party and the indemnified party shall have mutually agreed to the retention of such counsel or (ii) the named parties to any such proceeding (including any impleaded parties) include both the indemnifying party and the indemnified party and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. It is understood that the indemnifying party shall not, in respect of the legal expenses of any indemnified party in connection with any proceeding or related proceedings in the same jurisdiction, be liable for (i) the reasonable fees and expenses of more than one separate firm (in addition to any local counsel) for all Underwriters and all persons, if any, who control any Underwriter within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act or who are affiliates of any Underwriter within the meaning of Rule 405 under the Securities Act and (ii) the reasonable fees and expenses of more than one separate firm (in addition to any local counsel) for

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the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of either such Section, and that all such fees and expenses shall be reimbursed as they are incurred. In the case of any such separate firm for the Underwriters and such control persons and affiliates of any Underwriters, such firm shall be designated in writing by the Representatives. In the case of any such separate firm for the Company, and such directors, officers and control persons of the Company, such firm shall be designated in writing by the Company. The indemnifying party shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party from and against any loss or liability by reason of such settlement or judgment. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened proceeding in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party, unless such settlement (i) includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such proceeding and (ii) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of such indemnified party.

(d) To the extent the indemnification provided for in Section 8(a) or 8(b) is unavailable to an indemnified party or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each indemnifying party under such paragraph, in lieu of indemnifying such indemnified party thereunder, shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the indemnifying party or parties on the one hand and the indemnified party or parties on the other hand from the offering of the Notes or (ii) if the allocation provided by clause 8(d)(i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause 8(d)(i) above but also the relative fault of the indemnifying party or parties on the one hand and of the indemnified party or parties on the other hand in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Underwriters on the other hand in connection with the offering of the Notes shall be deemed to be in the same respective proportions as the net proceeds from the offering of the Notes (before deducting expenses) received by the Company and the total underwriting discounts and commissions received by the Underwriters, in each case as set forth on the cover of the Prospectus, bear to the aggregate Public Offering Price of the Notes. The relative fault of the Company on the one hand and the Underwriters on the other hand shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Underwriters’ respective obligations to contribute pursuant to this Section 8 are several in proportion to the respective aggregate principal amount of Notes they have purchased hereunder, and not joint.

(e) The Company and the Underwriters agree that it would not be just or equitable if contribution pursuant to this Section 8 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in Section 8(d). The amount paid or payable by an

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indemnified party as a result of the losses, claims, damages and liabilities referred to in the immediately preceding paragraph shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 8, no Underwriter shall be required to contribute any amount in excess of the amount by which the underwriting commissions received by such Underwriter in connection with the Notes underwritten by it and distributed to the public exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The remedies provided for in this Section 8 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any indemnified party at law or in equity.

(f) The indemnity and contribution provisions contained in this Section 8 and the representations, warranties and other statements of the Company contained in this Agreement shall remain operative and in full force and effect regardless of (i) any termination of this Agreement, (ii) any investigation made by or on behalf of any Underwriter, any person controlling any Underwriter or any affiliate of any Underwriter, or the Company, its officers or directors or any person controlling the Company and (iii) acceptance of and payment for any of the Notes.

9. Termination. The Underwriters may terminate this Agreement by notice given by the Representatives to the Company, if after the execution and delivery of this Agreement and on or prior to the Closing Date (i) trading generally shall have been suspended or materially limited on, or by, as the case may be, any of the New York Stock Exchange or the Nasdaq National Market, (ii) trading of any securities of the Company shall have been suspended on any exchange or in any over-the-counter market, (iii) a material disruption in securities settlement or clearance services in the United States shall have occurred, (iv) any moratorium on commercial banking activities shall have been declared by Federal or New York State authorities or (v) there shall have occurred any outbreak or escalation of hostilities, or any change in financial markets or any calamity or crisis that, in the Representatives’ judgment, is material and adverse and which, singly or together with any other event specified in this clause (v), makes it, in the Representatives’ judgment, impracticable or inadvisable to proceed with the offer, sale or delivery of the Notes on the terms and in the manner contemplated in the Prospectus.

10. Effectiveness; Defaulting Underwriters. This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

If, on the Closing Date, any one or more of the Underwriters shall fail or refuse to purchase Notes that it has or they have agreed to purchase hereunder on such date, and the aggregate principal amount of Notes which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase is not more than one-tenth of the aggregate principal amount of the Notes to be purchased on such date, the other Underwriters shall be obligated severally in the proportions that the aggregate principal amount of Notes set forth opposite their respective names in Schedule I bears to the aggregate principal amount of Notes set forth opposite the

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names of all such non-defaulting Underwriters, or in such other proportions as the Representatives may specify, to purchase the Notes which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date; provided that in no event shall the aggregate principal amount of Notes that any Underwriter has agreed to purchase pursuant to this Agreement be increased pursuant to this Section 10 by an amount in excess of one-ninth of such aggregate principal amount of Notes without the written consent of such Underwriter. If, on the Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Notes and the aggregate principal amount of Notes with respect to which such default occurs is more than one-tenth of the aggregate principal amount of Notes to be purchased, and arrangements satisfactory to the Representatives and the Company for the purchase of such Notes are not made within 36 hours after such default, this Agreement shall terminate without liability on the part of any non-defaulting Underwriter or the Company, except that the provisions of Sections 7 (Expenses), 8 (Indemnity and Contribution), 11 (Reimbursement of Underwriters’ Expenses) and 17 (Governing Law Provisions) shall at all times be effective and shall survive such termination. In any such case either the Representatives or the Company shall have the right to postpone the Closing Date, but in no event for longer than seven days, in order that the required changes, if any, in the Registration Statement, any Issuer Free Writing Prospectus, the Preliminary Prospectus and the Prospectus or in any other documents or arrangements may be effected. Any action taken under this paragraph shall not relieve any defaulting Underwriter from liability in respect of any default of such Underwriter under this Agreement. As used in this Agreement, the term “Underwriters” shall be deemed to include any person substituted for a defaulting Underwriter under this Section 10.

11. Reimbursement of Underwriters’ Expenses. If this Agreement shall be terminated by the Underwriters, or any of them, because of any failure or refusal on the part of the Company to comply with the terms or to fulfill any of the conditions of this Agreement, or if for any reason the Company shall be unable to perform its obligations under this Agreement, the Company will, upon demand, reimburse the Underwriters or such Underwriters as have so terminated this Agreement with respect to themselves, severally, for all out-of-pocket expenses (including the fees and disbursements of their counsel) reasonably incurred by such Underwriters in connection with this Agreement or the offering contemplated hereunder.

12. No Fiduciary Duty. The Company acknowledges and agrees that: (i) the purchase and sale of the Notes pursuant to this Agreement, including the determination of the public offering price of the Notes and any related discounts and commissions, is an arm’s length commercial transaction between the Company, on the one hand, and the several Underwriters, on the other hand, and the Company is capable of evaluating, and understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement, (ii) in connection with each transaction contemplated hereby and the process leading to such transaction each Underwriter is and has been acting solely as a principal and is not the advisor, agent or fiduciary of the Company, any of its affiliates or any person or entity, (iii) no Underwriter has assumed or will assume an advisory, agency or fiduciary responsibility in favor of the Company with respect to any of the transactions contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company on other matters) and no Underwriter has any obligation to the Company with respect to the offering contemplated hereby except the obligations expressly set forth in this Agreement, (iv) the several Underwriters and their respective affiliates may be engaged in a broad range of transactions that involve interests that differ

22

from those of the Company and that the several Underwriters have no obligation to disclose any of such interests by virtue of any advisory, agency or fiduciary relationship, and (v) the Underwriters have not provided any legal, accounting, regulatory or tax advice with respect to the offering contemplated hereby and the Company has consulted its own legal, accounting, regulatory and tax advisors to the extent it deemed appropriate.

13. Entire Agreement. This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company and the several Underwriters with respect to the subject matter hereof, excluding the Amended & Restated Engagement Letter dated November 18, 2008 by and among the Company, Banc of America Securities LLC and UBS Securities LLC (the “Engagement Letter”). The Company, Banc of America Securities LLC and UBS Securities LLC hereby acknowledge that all obligations under the Engagement Letter with respect to this offering have been terminated. The Company hereby waives and releases, to the fullest extent permitted by law, any claims that the Company may have against the several Underwriters with respect to any breach or alleged breach of agency or fiduciary duty.

14. Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted by any standard form of telecommunication. Notices to the Underwriters shall be directed to the Representatives at Banc of America Securities LLC, 00 Xxxx 00^xx Xxxxxx, Xxx Xxxx, Xxx Xxxx 00000, Attention: High Grade Debt Capital Markets Transaction Management/Legal, Facsimile: (000) 000-0000 and UBS Securities LLC, 000 Xxxxxxxxxx Xxxxxxxxx, Xxxxxxxx, Xxxxxxxxxxx 00000, Attention: Fixed Income Syndicate, Facsimile: (000) 000-0000; and notices to the Company shall be directed to it at 00 Xxxxx Xxxxxx Xxxxx, Xxxxxxx, Xxxxxxxx, Attention: Xxxxxxxx X. Xxxxxx, Managing Director, General Counsel and Corporate Secretary, Facsimile (000) 000-0000.

15. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto, including any substitute Underwriters pursuant to Section 10 hereof, and to the benefit of the directors, officers, employees, agents and controlling persons referred to in Section 8, and in each case their respective successors, and no other person will have any right or obligation hereunder. The term “successors” shall not include any purchaser of the Notes as such from any of the Underwriters merely by reason of such purchase.

16. Partial Unenforceability. The invalidity or unenforceability of any Section, paragraph or provision of this Agreement shall not affect the validity or enforceability of any other Section, paragraph or provision hereof. If any Section, paragraph or provision of this Agreement is for any reason determined to be invalid or unenforceable, there shall be deemed to be made such minor changes (and only such minor changes) as are necessary to make it valid and enforceable.

17. Governing Law Provisions. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK APPLICABLE TO AGREEMENTS MADE AND TO BE PERFORMED IN THAT STATE.

23

Any legal suit, action or proceeding arising out of or based upon this Agreement or the transactions contemplated hereby may be instituted in the federal courts of the United States of America located in the City and County of New York, Borough of Manhattan, or the courts of the State of New York in each case located in the City and County of New York, Borough of Manhattan (collectively, the “Specified Courts”), and each party irrevocably submits to the exclusive jurisdiction (except for proceedings instituted in regard to the enforcement of a judgment of any such court, as to which such jurisdiction is non-exclusive) of such courts in any such suit, action or proceeding. Service of any process, summons, notice or document by mail to such party’s address set forth above shall be effective service of process for any suit, action or other proceeding brought in any such court. The parties irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the Specified Courts and irrevocably and unconditionally waive and agree not to plead or claim in any such court that any such suit, action or other proceeding brought in any such court has been brought in an inconvenient forum.

18. General Provisions. This Agreement may be executed in two or more counterparts, each one of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument. This Agreement may not be amended or modified unless in writing by all of the parties hereto, and no condition herein (express or implied) may be waived unless waived in writing by each party whom the condition is meant to benefit. The Section headings herein are for the convenience of the parties only and shall not affect the construction or interpretation of this Agreement.

Each of the parties hereto acknowledges that it is a sophisticated business person who was adequately represented by counsel during negotiations regarding the provisions hereof, including, without limitation, the indemnification and contribution provisions of Section 8, and is fully informed regarding said provisions. Each of the parties hereto further acknowledges that the provisions of Section 8 hereto fairly allocate the risks in light of the ability of the parties to investigate the Company, its affairs and its business in order to assure that adequate disclosure has been made in the Registration Statement, the Disclosure Package and the Prospectus (and any amendments and supplements thereto), as required by the Securities Act and the Exchange Act.

24

Very truly yours,
CME GROUP INC.
By:		/s/ Xxxxx X. Xxxxxx
Name:		Xxxxx X. Xxxxxx
Title:		Director and Treasurer

Accepted as of the date hereof
Banc of America Securities LLC
UBS Securities LLC
Lloyds TSB Bank plc
Barclays Capital Inc.
Acting severally on behalf of themselves and the several Underwriters named in Schedule I hereto.
By:		Banc of America Securities LLC
By:		/s/ Xxxx Xxxxx
Name:		Xxxx Xxxxx
Title:		Principal
By:		UBS Securities LLC
By:		/s/ Xxxxxx Xxxxx
Name:		Xxxxxx Xxxxx
Title:		Managing Director UBS Securities LLC
By:		/s/ Xxxxxx Xxxx
Name:		Xxxxxx Xxxx
Title:		Executive director Debt Capital Markets
By:		Lloyds TSB Bank plc
By:		/s/ Xxxxxxxx Xxxxxxx
Name:		Xxxxxxxx Xxxxxxx
Title:		Director
By:		Barclays Capital Inc.
By:		/s/ Xxxxxx Xxxxxxx
Name:		Xxxxxx Xxxxxxx
Title:		Director

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SCHEDULE I

Underwriter		Aggregate Principal Amount of Notes To Be Purchased
Banc of America Securities LLC		$	167,325,000
UBS Securities LLC			167,325,000
Barclays Capital Inc.			86,550,000
Lloyds TSB Bank plc			115,350,000
BMO Capital Markets Corp.			86,550,000
Mitsubishi UFJ Securities International plc			86,550,000
Scotia Capital (USA) Inc.			28,875,000
PNC Capital Markets LLC			11,550,000
Total		$	750,000,000

S-I-1

SCHEDULE II

Issuer Free Writing Prospectuses

Final Term Sheet dated February 4, 2009

S-II-1

SCHEDULE III

Form of Final Term Sheet

$750,000,000 5.75% Notes due February 15, 2014

TERM SHEET

Issuer:		CME Group Inc.
Security Type:		SEC Registered Senior Unsecured Notes
Expected Ratings:		Aa3 (Xxxxx’x) / AA (S&P)
Size:		$750,000,000
Trade Date:		February 4, 2009
Settlement Date:		February 9, 2009 (T+3)
Maturity:		February 15, 2014
Interest Rate Per Annum:		5.75%
Interest Payment Dates:		Semiannually, on February 15 and August 15 of each year
First Interest Payment Date:		August 15, 2009
Optional Redemption:		Make-whole redemption at any time at a discount rate of Treasury plus 50 bps
Public Offering Price:		99.839%
Treasury Benchmark:		1.75% Notes due 2014
Treasury Benchmark Price:		$99-07+
Treasury Benchmark Yield:		1.912%
Re-offer Spread vs. Treasury:		+ 387.5 bps
Yield to Maturity:		5.787%
Gross Fees		0.455%
Net Proceeds:		$745,380,000
Mandatory Offer to Repurchase Notes:		In the event of a “Change of Control Triggering Event” (as defined in the preliminary prospectus supplement) at 101% of the principal amount, plus accrued and unpaid interest
Day Count:		30/360
Payment Business Days:		New York
Payment Convention:		Following, Unadjusted
Minimum Denomination / Multiples:		$2,000 / $1,000
CUSIP / ISIN:		12572Q AD7 / US12572QAD79
Joint Bookrunning Managers:		Banc of America Securities LLC (22.31%) UBS Securities LLC (22.31%) Barclays Capital Inc (11.54%) Lloyds TSB Bank plc (15.38%)
Joint Lead Managers:		BMO Capital Markets Corp. (11.54%) Mitsubishi UFJ Securities International plc (11.54%)
Co-Managers:		Scotia Capital (USA) Inc. (3.85%) PNC Capital Markets LLC (1.54%)

Note: A securities rating is not a recommendation to buy, sell, or hold securities and may be subject to revision or withdrawal at any time.

The issuer has filed a registration statement (including a prospectus) with the Securities and Exchange Commission for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the Securities and Exchange Commission for more complete information about the issuer and this offering. You may get these documents for free by visiting XXXXX on the Securities and Exchange Commission’s website at xxx.xxx.xxx. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling Banc of America Securities LLC toll-free at 1-800-294-1322, UBS Securities LLC toll-free at 0-000-000-0000, ext. 561 3884, Barclays Capital Inc toll free 0-000-000-0000 (ext. 2663), or Lloyds TSB Corporate Markets + 44 207 158 2016.

This communication should be read in conjunction with the preliminary prospectus supplement dated February 4, 2009 and the accompanying prospectus dated March 17, 2006.

S-III-1

Exhibit A

CME GROUP INC.

Matters to be Covered by Opinion of Issuer’s Outside Counsel

1. The Company has been duly incorporated and is validly existing in good standing under the laws of the State of Delaware.

2. The Subsidiaries have been duly incorporated and are validly existing in good standing under the laws of the State of Delaware.

3. The Company has the status set forth in a schedule to such opinion set forth opposite the jurisdictions listed in such schedule.

4. The Subsidiaries have the status set forth in a schedule to such opinion set forth opposite the jurisdictions listed in such schedule.

5. The Company has the corporate power and corporate authority to execute and deliver the Underwriting Agreement, the Indenture and the Notes and to consummate the transactions contemplated thereby.

6. The Underwriting Agreement has been duly authorized, executed and delivered by the Company.

7. The Indenture has been duly authorized, executed and delivered by the Company and is a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms.

8. The execution and delivery by the Company of the Underwriting Agreement, the Indenture and the Notes and the consummation by the Company of the transactions contemplated thereby, including the issuance and sale of the Notes, will not (i) conflict with the certificate of incorporation or bylaws of the Company, (ii) constitute a violation of, or a breach or default under, the terms of any Applicable Contract or (iii) violate or conflict with, or result in any contravention of, any Applicable Law or any Applicable Order (provided, that no opinion shall be expressed as to whether the execution, delivery or performance by the Company of the Underwriting Agreement, the Indenture or the Notes will constitute a violation of, or a default under, any covenant, restriction or provision with respect to financial ratios or tests or any aspect of the financial condition or results of operations of the Company or any of its subsidiaries).

9. No Governmental Approval, which has not been obtained or taken and is not in full force and effect, is required to authorize, or is required for, the execution or delivery of the Underwriting Agreement, the Indenture or the Notes by the Company or the consummation by the Company of the transactions contemplated thereby.

A-1

10. To the knowledge of such counsel, there are no legal or governmental proceedings pending to which the Company is a party or to which any property of the Company is subject that are required to be disclosed in the Preliminary Prospectus, considered together with the Final Term Sheet, or the Prospectus pursuant to Item 103 of Regulation S-K that are not so disclosed.

11. The Notes have been duly authorized and executed by the Company, and when duly authenticated by the Trustee and issued and delivered by the Company against payment therefor in accordance with the terms of the Underwriting Agreement and the Indenture, the Notes will constitute valid and binding obligations of the Company entitled to the benefits of the Indenture and enforceable against the Company in accordance with their terms.

12. The statements in each of the Preliminary Prospectus, considered together with the Final Term Sheet, and the Prospectus under the captions “Description of the Notes” and “Description of Debt Securities” other than “Book-Entry Delivery and Settlement,” insofar as such statements purport to summarize certain provisions of the Indenture and the Notes, insofar as such statements purport to summarize certain provisions of the specific agreement referred to therein, fairly summarize such provisions in all material respects.

13. The Company is not and, after giving effect to the offering and sale of the Notes and the use of the proceeds therefrom as described in the Preliminary Prospectus, considered together with the Final Term Sheet, and the Prospectus will not be, an “investment company” subject to registration and regulation, as such term is defined in the Investment Company Act of 1940, as amended.

14. Although the discussion set forth in the Preliminary Prospectus and the Prospectus under the caption “Material United States Federal Income Tax Consequences” does not purport to discuss all possible United States federal income tax consequences of the ownership of the Notes, such discussion constitutes, in all material respects, a fair and accurate summary of the United States federal income tax consequences of the ownership of the Notes, subject to the qualifications set forth in such discussion.

In addition, such counsel shall state that the Registration Statement became effective upon filing with the Commission pursuant to Rule 462 of the Securities Act and, pursuant to Section 309 of the Trust Indenture Act, the Indenture has been qualified under the Trust Indenture Act, and that such counsel has been orally advised by the Commission that no stop order suspending the effectiveness of the Registration Statement has been issued and, to such counsel’s knowledge, no proceedings for that purpose have been instituted or are pending or threatened by the Commission.

In addition, such counsel shall state that such counsel has participated in conferences with officers and other representatives of the Company, counsel for the Company, representatives of the independent registered public accountants of the Company and the Representatives and counsel for the Underwriters at which the contents of the Registration Statement, the Preliminary Prospectus, the Prospectus and the Disclosure Package and related matters were discussed. Such counsel shall state that such counsel did not participate in the preparation of the documents incorporated by reference in the Registration Statement but has, however, reviewed

A-2

such documents and discussed the business and affairs of the Company with officers and other representatives of the Company. Such counsel need not pass upon, nor assume any responsibility for, the accuracy, completeness or fairness of the statements contained or incorporated by reference in the Registration Statement, the Preliminary Prospectus, the Prospectus or the Disclosure Package and need not make any independent check or verification thereof (except to the limited extent referred to in paragraph 12 above). On the basis of the foregoing, such counsel shall state that (i) the Registration Statement, at the Initial Sale Time and the Prospectus, as of the date of the final prospectus supplement relating to the Notes, appeared on their face to be appropriately responsive in all material respects to the requirements of the Securities Act and the General Rules and Regulations under the Securities Act (except that in each case such counsel does not express any view as to the financial statements, schedules and other financial information included or incorporated by reference therein or excluded therefrom or the Statement of Eligibility on Form T-1 (the “Form T-1”)) and (ii) no facts have come to such counsel’s attention that have caused such counsel to believe that the Registration Statement, at the Initial Sale Time, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading or that the Prospectus, as of the date of the final prospectus supplement relating to the Notes or as of the Closing Date, contained or contains an untrue statement of a material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading (except that in each case such counsel does not express any view as to the financial statements, schedules and other financial information included or incorporated by reference therein or excluded therefrom or the statements contained in the exhibits to the Registration Statement, including the Form T-1). In addition, on the basis of the foregoing, such counsel shall state that no facts have come to such counsel’s attention that have caused such counsel to believe that the Disclosure Package, as of the Initial Sale Time, contained an untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading (except that such counsel does not express any view as to the financial statements, schedules and other financial information included or incorporated by reference therein or excluded therefrom or the statements contained in the exhibits to the Registration Statement, including the Form T-1).

For the purposes of the foregoing:

“Applicable Contracts” means those agreements or instruments set forth on a schedule to the opinion.¹

“Applicable Laws” means the General Corporation Law of the State of Delaware, those laws, rules and regulations of the State of New York and those federal laws, rules and regulations of the United States of America, in each case that, in such counsel’s experience, are normally applicable to transactions of the type contemplated by the Underwriting Agreement, the Indenture and the

¹ Applicable Contracts will be limited to the material agreements filed as exhibits to the Company’s 2007 Form 10-K, first quarter 2008 Form 10-Q, second quarter 2008 Form 10-Q, third quarter 2008 Form 10-Q or any Form 8-K filed during 2008 and 2009, in each case in the form filed with the Commission.

A-3

Notes (other than the United States federal securities laws, state securities laws or blue sky laws, antifraud laws and the rules and regulations of the Financial Industry Regulatory Authority, Inc.), but without the making by such counsel of any special investigation as to the applicability of any specific law, rule or regulation.

“Applicable Orders” means those judgments, orders or decrees identified on a schedule to the Company Certificate.

“Company Certificate” means the certificate of an executive officer of the Company, a copy of which certificate shall be attached to such counsel’s opinion.

“Governmental Authorities” means any court, regulatory body, administrative agency or governmental body of the State of Delaware or New York or the United States of America having jurisdiction over the Company under Applicable Laws.

“Government Approval” means any consent, approval, license, authorization or validation of, or filing, qualification or registration with, any Governmental Authority required to be made or obtained by the Company pursuant to Applicable Laws, other than any consent, approval, license, authorization, validation, filing, qualification or registration that may have become applicable a result of the involvement of any party (other than the Company) in the transactions contemplated by the Underwriting Agreement, the Indenture and the Notes or because of such parties’ legal or regulatory status or because of any other facts specifically pertaining to such parties.

Such opinion shall contain qualifications and assumptions normally contained in such opinions in similar transactions.

A-4

Exhibit B

CME GROUP INC.

Matters to be Covered by Opinion of Issuer’s General Counsel

1. The statements in the Annual Report on Form 10-K under the caption “Regulatory Matters,” in each case insofar as such statements constitute a summary of certain provisions of specific agreements, statutes or regulations referred to therein, fairly present and summarize, in all material respects, such provisions referred to therein (it being understood that such counsel expresses no opinion with respect to the status of any legislative matters).

2. The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus, as of the time they were filed with the Commission, complied as to form in all material respects with the requirements of the Exchange Act.

3. To her knowledge, there are no contracts or documents which are required to be described in the Registration Statement, the Preliminary Prospectus, the Prospectus or the documents incorporated by reference therein or to be filed as exhibits to the Registration Statement which have not been so described and filed as required.

4. All of the issued shares of capital stock of each Subsidiary of the Company have been duly authorized and validly issued, are fully paid and non-assessable and are owned by the Company free and clear of any security interest, mortgage, pledge, lien, encumbrance or claim.