Underwriting Agreement for Common Stock Offering between CF Industries Holdings, Inc. and Underwriters (2005)

Exhibit 1.1

[                        ] Shares

CF INDUSTRIES HOLDINGS, INC.

COMMON STOCK, PAR VALUE $0.01 PER SHARE

         UNDERWRITING AGREEMENT

                        , 2005

                        , 2005

Morgan Stanley & Co. Incorporated
J.P. Morgan Securities Inc.
Banc of America Securities LLC
Credit Suisse First Boston LLC
Harris Nesbitt Corp.
ABN AMRO Rothschild LLC
CIBC World Markets Corp.

c/o Morgan Stanley & Co. Incorporated
    1585 Broadway
    New York, New York 10036

    J.P. Morgan Securities Inc.
    277 Park Avenue
    9th Floor
    New York, New York 10172

Dear Sirs and Mesdames:

        CF Industries Holdings, Inc., a Delaware corporation (the "Company"), proposes to issue and sell to the several Underwriters named in Schedule I hereto (the "Underwriters") [            ] shares of its common stock, par value $0.01 per share (the "Firm Shares").

        The Company also proposes to issue and sell to the several Underwriters not more than an additional [            ] shares of its common stock, par value $0.01 per share (the "Additional Shares"), if and to the extent that you, as Managers of the offering, shall have determined to exercise, on behalf of the Underwriters, the right to purchase such shares of common stock granted to the Underwriters in Section 2 hereof. The Firm Shares and the Additional Shares are hereinafter collectively referred to as the "Shares." References herein to Common Stock include the related rights to acquire Series A Junior Participating Preferred Stock of the Company under the Rights Agreement dated as of [                        ], 2005, between the Company and The Bank of New York, as rights agent (the "Rights"). The shares of common stock, par value $0.01 per share, of the Company to be outstanding after giving effect to the sales contemplated hereby are hereinafter referred to as the "Common Stock."

        The Shares are being sold following a reorganization (the "Reorganization") of CF Industries, Inc., a Delaware corporation ("CF"), into a holding company structure pursuant to an Agreement and Plan of Merger dated as of [                        ], 2005, among the Company, CF and CF Merger Corp. (the "Merger Agreement"). Upon consummation of the Reorganization, CF will become a direct, wholly owned subsidiary of the Company.

        The Company has filed with the Securities and Exchange Commission (the "Commission") a registration statement (file no. 333-124949), including a prospectus, relating to the Shares. The registration statement as amended at the time it becomes effective, including the information (if any) deemed to be part of the registration statement at the time of effectiveness pursuant to Rule 430A under the Securities Act of 1933, as amended (the "Securities Act"), is hereinafter referred to as the "Registration Statement"; the prospectus in the form first used to confirm sales of Shares is hereinafter referred to as the "Prospectus." If the Company has filed an abbreviated registration statement to register additional shares of Common Stock pursuant to Rule 462(b) under the Securities Act (the "Rule 462 Registration Statement"), then any reference herein to the term "Registration Statement" shall be deemed to include such Rule 462 Registration Statement.

        Morgan Stanley & Co. Incorporated ("Morgan Stanley") has agreed to reserve a portion of the Shares to be purchased by it under this Agreement for sale to the Company's and CF's directors, officers, employees and former officers (collectively, "Participants"), as set forth in the Prospectus under the heading "Underwriters" (the "Directed Share Program"). The Shares to be sold by Morgan Stanley and its affiliates pursuant to the Directed Share Program are referred to hereinafter as the "Directed Shares." Any Directed Shares not orally confirmed for purchase by any Participant by the end of the business day on which this Agreement is executed will be offered to the public by the Underwriters as set forth in the Prospectus.

        1.    Representations and Warranties.    The Company represents and warrants to and agrees with each of the Underwriters that:

        (a)   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.

        (b)   (i) The Registration Statement, when it became effective, did not contain and, as amended or supplemented, if applicable, 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, (ii) the Registration Statement and the Prospectus comply and, as amended or supplemented, if applicable, will comply in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder and (iii) the Prospectus does not contain and, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that the representations and warranties set forth in this paragraph do not apply to statements or omissions in the Registration Statement or the Prospectus based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through you expressly for use therein.

        (c)   Each of the Company and CF has been duly incorporated, is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation, has the corporate power and authority to own its property and to conduct its business as described in 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, CF and their respective subsidiaries (collectively, the "CF Group" and each, a "member" of the CF Group), taken as a whole.

        (d)   Each subsidiary of the Company and CF has been duly incorporated, is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation, has the corporate power and authority to own its property and to conduct its business as described in 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 CF Group, taken as a whole; all of the issued shares of capital stock of each subsidiary of the Company and CF have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company or CF, as applicable, free and clear of all liens, encumbrances, equities or claims, except as described in the Prospectus.

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

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

        (g)   As of the date hereof, no shares of Common Stock are outstanding. The shares of Common Stock to be issued pursuant to the Merger Agreement have been duly authorized and, when issued in accordance with the terms of the Merger Agreement, will be validly issued, fully paid and non-assessable.

        (h)   The Shares have been duly authorized and, when issued and delivered in accordance with the terms of this Agreement, will be validly issued, fully paid and non-assessable, and the issuance of such Shares will not be subject to any preemptive or similar rights.

        (i)    The execution and delivery by the Company of, and the performance by the Company of its obligations under, this Agreement will not breach or contravene (A) any provision of applicable law, (B) the certificate of incorporation or by-laws of the Company, (C) any agreement or other instrument binding upon any member of the CF Group, or (D) any judgment, order or decree of any governmental body, agency or court having jurisdiction over any member of the CF Group, except for any breach or contravention described in clause (A), (C) or (D) as would not, singly or in the aggregate, have a material adverse effect on the CF Group, taken as a whole; and no consent, approval, authorization or

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order of, or qualification with, any governmental body or agency is required for the performance by the Company of its obligations under this Agreement, except where the failure to obtain or have any such consent, approval, authorization, order or qualification would not, singly or in the aggregate, have a material adverse effect on the CF Group, taken as a whole, and except (i) such as may have been obtained, (ii) such as may be required by the securities or Blue Sky laws of the various states in connection with the offer and sale of the Shares, (iii) such as may be required with respect to the transactions contemplated by the Merger Agreement, (iv) the filing of the Prospectus under Rule 424(b) under the Securities Act with the Commission and (v) the filing of a registration statement on Form 8-A relating to the Common Stock with the Commission, which, in the case of clauses (iii), (iv) and (v) above, shall be obtained or made on or prior to the Closing Date.

        (j)    There has not occurred any material adverse change, or any development involving a prospective material adverse change, in the condition, financial or otherwise, or in the earnings, business or operations of the CF Group, taken as a whole, from that set forth in the Prospectus (exclusive of any amendments or supplements thereto subsequent to the date of this Agreement).

        (k)   There are no legal or governmental proceedings pending or, to the knowledge of the Company, threatened to which any member of the CF Group is a party or to which any of the properties of any member of the CF Group is subject that are required to be described in the Registration Statement or the Prospectus and are not so described or any statutes, regulations, contracts or other documents that are required to be described in the Registration Statement or the Prospectus or to be filed as exhibits to the Registration Statement that are not described or filed as required.

        (l)    Each preliminary prospectus filed as part of the registration statement as originally filed or as part of any amendment thereto, or filed pursuant to Rule 424 under the Securities Act, complied when so filed in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder.

        (m)  The Company is not, and after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Prospectus will not be, required to register as an "investment company" as such term is defined in the Investment Company Act of 1940, as amended.

        (n)   Except as disclosed in the Prospectus, the CF Group (i) is in compliance with any and all applicable foreign, federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants ("Environmental Laws"), (ii) has received all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses and (iii) is in compliance with all terms and conditions of any such permit, license or approval, except, with respect to clauses (i), (ii) and (iii) above, where such noncompliance with Environmental Laws, failure to receive required permits, licenses or other approvals or failure to comply with the terms and conditions of such permits, licenses or approvals would not, singly or in the aggregate, have a material adverse effect on the CF Group, taken as a whole.

        (o)   Except as disclosed in the Prospectus, there are no known costs or liabilities associated with Environmental Laws (including, without limitation, any capital or operating expenditures required for clean-up, closure of properties or compliance with Environmental Laws or any permit, license or approval, any related constraints on operating activities and any potential liabilities to third parties) which would, singly or in the aggregate, have a material adverse effect on the CF Group, taken as a whole.

        (p)   Except as disclosed in the Prospectus, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Securities Act with respect to any securities of the Company or to require the Company to include such securities with the Shares registered pursuant to the Registration Statement.

        (q)   Subsequent to the respective dates as of which information is given in the Registration Statement and the Prospectus, (i) no member of the CF Group has incurred any material liability or obligation, direct or contingent, or entered into any material transaction, except for product sales, supply purchases and related hedging activities in the ordinary course of business or except as described in the Prospectus; (ii) the Company has not purchased any of its outstanding capital stock, nor declared, paid

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or otherwise made any dividend or distribution of any kind on its capital stock other than ordinary and customary dividends; and (iii) there has not been any material change in the capital stock, short-term debt or long-term debt of any member of the CF Group, except in each case as described in the Prospectus or as contemplated by the Merger Agreement.

        (r)   The CF Group has good and marketable title in fee simple to all real property and good and marketable title to all personal property owned by them which is material to the business of the CF Group, taken as a whole, in each case free and clear of all liens, encumbrances and defects except such as are described in the Prospectus or such as do not materially affect the value of such property and do not materially interfere with the use made and proposed to be made of such property by the CF Group; and any real property and buildings held under lease by the CF Group are held by them under valid, subsisting and enforceable leases with such exceptions as are not material to the CF Group and do not materially interfere with the use made and proposed to be made of such property and buildings by the Company and its subsidiaries, in each case except as described in the Prospectus.

        (s)   The CF Group owns or possesses, or can acquire on reasonable terms, all 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 it in connection with the business now operated by it, except where the failure to own, possess or acquire any of the foregoing would not result in a material adverse effect on the CF Group, taken as a whole; and no member of the CF Group 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 on the CF Group, taken as a whole.

        (t)    No material labor dispute with the employees of the CF Group exists, except as described in the Prospectus, or, to the knowledge of the Company, is imminent.

        (u)   The CF Group is insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as are customary in the businesses in which they are engaged; and no member of the CF Group (i) has been refused any material insurance coverage sought or applied for; or (ii) has any reason to believe that it will not be able to renew any existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a material adverse effect on the CF Group, taken as a whole, except as described in the Prospectus.

        (v)   The CF Group possesses all certificates, authorizations and permits issued by the appropriate federal, state or foreign regulatory authorities necessary to conduct its business as presently conducted, except as described in the Prospectus or where the failure to possess such certificates, authorizations and permits would not, singly or in the aggregate, have a material adverse effect on the CF Group, taken as a whole; and no member of the CF Group has received any notice of proceedings relating to the revocation or modification of any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a material adverse effect on the CF Group, taken as a whole, except as described in the Prospectus.

        (w)  CF and its subsidiaries maintain a 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 generally accepted accounting principles 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. Except as described in the Prospectus, since the end of the CF's most recent audited fiscal year, there has been (i) no material weakness in CF's internal control over financial reporting (whether or not remediated) and (ii) no change in CF's internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, CF's internal control over financial reporting.

        (x)   Except as described in the Prospectus (exclusive of any amendments or supplements thereto subsequent to the date of this Agreement), the Company has not sold, issued or distributed any shares of Common Stock during the six-month period preceding the date hereof, including any sales pursuant

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to Rule 144A under, or Regulation D or S of, the Securities Act, other than shares issued pursuant to employee benefit plans, qualified stock option plans or other employee compensation plans or pursuant to outstanding options, rights or warrants.

        (y)   The Registration Statement, the Prospectus and any preliminary prospectus comply, and any amendments or supplements thereto will comply, with any applicable laws or regulations of foreign jurisdictions in which the Prospectus or any preliminary prospectus, as amended or supplemented, if applicable, are distributed in connection with the Directed Share Program.

        (z)   No consent, approval, authorization or order of, or qualification with, any governmental body or agency, other than those obtained, is required in connection with the offering of the Directed Shares in any jurisdiction where the Directed Shares are being offered.

        (aa) The Company has not offered, or caused Morgan Stanley to offer, Shares to any person pursuant to the Directed Share Program with the specific intent to unlawfully influence (i) a customer or supplier of the Company or CF to alter the customer's or supplier's level or type of business with the Company or CF, or (ii) a trade journalist or publication to write or publish favorable information about the Company or CF or CF's products.

        (bb) The Shares have been duly approved for listing, subject only to official notice of issuance, on the New York Stock Exchange, Inc. ("NYSE").

        (cc) The CF Group has filed all foreign, federal, state and local tax returns that are required to be filed, or have duly requested extensions thereof, and have paid all taxes required to be paid by them and any other assessment, fine or penalty levied against them, except in each case in which the failure to so file or pay would not have a material adverse effect on the CF Group, taken as a whole. The charges, accruals and reserves on the books of the Company and CF in respect of any income and corporation tax liability for any years not finally determined are adequate to meet any assessments or re-assessments for additional income or corporation tax for any years not finally determined, except to the extent of any inadequacy that would not have a material adverse effect on the CF Group, taken as a whole.

        2.    Agreements to Sell and Purchase.    The Company hereby agrees to 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 respective numbers of Firm Shares set forth in Schedule I hereto opposite its name at $[            ] a share (the "Purchase Price").

        On the basis of the representations and warranties contained in this Agreement, and subject to its terms and conditions, the Company agrees to sell to the Underwriters the Additional Shares, and the Underwriters shall have the right to purchase, severally and not jointly, up to [    ] Additional Shares at the Purchase Price. You may exercise this right on behalf of the Underwriters in whole or from time to time in part by giving written notice to the Company not later than 30 days after the date of this Agreement. Any exercise notice shall specify the number of Additional Shares to be purchased by the Underwriters and the date on which such shares are to be purchased. Each purchase date must be at least one business day after the written notice is given and may not be earlier than the closing date for the Firm Shares nor later than ten business days after the date of such notice. Additional Shares may be purchased as provided in Section 4 hereof solely for the purpose of covering over-allotments made in connection with the offering of the Firm Shares. On each day, if any, that Additional Shares are to be purchased (an "Option Closing Date"), each Underwriter agrees, severally and not jointly, to purchase the number of Additional Shares (subject to such adjustments to eliminate fractional shares as you may determine) that bears the same proportion to the total number of Additional Shares to be purchased on such Option Closing Date as the number of Firm Shares set forth in Schedule I hereto opposite the name of such Underwriter bears to the total number of Firm Shares.

        The Company hereby agrees that, without the prior written consent of Morgan Stanley on behalf of the Underwriters, it will not, during the period ending 180 days after the date of the Prospectus, (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in

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clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise or (3) file any registration statement with the Commission relating to the offering of any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (other than registration statement(s) on Form S-8 to register securities for issuance pursuant to the Company's stock incentive plan described in the Prospectus).

        The restrictions contained in the preceding paragraph shall not apply to (a) the Shares to be sold hereunder or (b) the issuance by the Company of shares of Common Stock upon the exercise of an option or warrant or the conversion of a security outstanding on the date hereof of which the Underwriters have been advised in writing, (c) the issuance by the Company of options and shares of Common Stock under the Company's equity incentive plan described in the Prospectus, (d) the issuance by the Company of shares of Common Stock pursuant to the Merger Agreement, (e) the issuance by the Company of equity securities pursuant to the Rights and (f) the entry into an agreement after the date that is 120 days after the date of the Prospectus for the issuance of shares of Common Stock in connection with any acquisitions, mergers or strategic investments, provided that the actual issuance of shares of Common Stock occurs after the expiration of the 180-day restricted period. Notwithstanding the foregoing, if (1) during the last 17 days of the 180-day restricted period the Company issues an earnings release or material news or a material event relating to the Company occurs; or (2) prior to the expiration of the 180-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 180-day period, the restrictions imposed by this agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event. The Company shall promptly notify Morgan Stanley of any earnings release, news or event that may give rise to an extension of the initial 180-day restricted period.

        3.    Terms of Public Offering.    The Company is advised by you that the Underwriters propose to make a public offering of their respective portions of the Shares as soon after the Registration Statement and this Agreement have become effective as in your judgment is advisable. The Company is further advised by you that the Shares are to be offered to the public initially at $[            ] a share (the "Public Offering Price") and to certain dealers selected by you at a price that represents a concession not in excess of $[            ] a share under the Public Offering Price, and that any Underwriter may allow, and such dealers may reallow, a concession, not in excess of $[            ] a share, to any Underwriter or to certain other dealers.

        4.    Payment and Delivery.    Payment for the Firm Shares shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Firm Shares for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on                        , 2005, or at such other time on the same or such other date, not later than                        , 2005, as shall be designated in writing by you. The time and date of such payment are hereinafter referred to as the "Closing Date."

        Payment for any Additional Shares shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Additional Shares for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on the date specified in the corresponding notice described in Section 2 or at such other time on the same or on such other date, in any event not later than            , 2005, as shall be designated in writing by you.

        The Firm Shares and Additional Shares shall be registered in such names and in such denominations as you shall request in writing not later than one full business day prior to the Closing Date or the applicable Option Closing Date, as the case may be. The Firm Shares and Additional Shares shall be delivered to you on the Closing Date or an Option Closing Date, as the case may be, for the respective accounts of the several Underwriters, with any transfer taxes payable in connection with the transfer of the Shares to the Underwriters duly paid, against payment of the Purchase Price therefor.

        5.    Conditions to the Underwriters' Obligations.    The obligations of the Company to sell the Shares to the Underwriters and the several obligations of the Underwriters to purchase and pay for the Shares on the Closing Date are subject to the condition that the Registration Statement shall have become effective not later than 4:00 p.m. (New York City time) on the date hereof.

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        The several obligations of the Underwriters are subject to the following further conditions:

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

          (i)  there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any review for a possible change that does not indicate the direction of the possible change, in the rating accorded any of the securities of the Company or CF by any "nationally recognized statistical rating organization," as such term is defined for purposes of Rule 436(g)(2) under the Securities Act; and

         (ii)  there shall not have occurred any change, or any development involving a prospective change, in the condition, financial or otherwise, or in the earnings, business or operations of the CF Group, taken as a whole, from that set forth in the Prospectus (exclusive of any amendments or supplements thereto subsequent to the date of this Agreement) that, in your judgment, is material and adverse and that makes it, in your judgment, impracticable to market the Shares on the terms and in the manner contemplated in the Prospectus.

        (b)   The Underwriters shall have received on the Closing Date a certificate, dated the Closing Date and signed by an executive officer of the Company, to the effect set forth in Section 5(a)(i) above and to the effect that the representations and warranties of the Company contained in this Agreement are true and correct as of the Closing Date and that the Company has complied in all material respects 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 officer signing and delivering such certificate may rely upon the best of his or her knowledge as to proceedings threatened.

        (c)   The Underwriters shall have received on the Closing Date an opinion and a letter of Skadden, Arps, Slate, Meagher & Flom LLP, special counsel for the Company, dated the Closing Date, to the effect set forth on Exhibit B-1 hereto.

        (d)   The Underwriters shall have received on the Closing Date an opinion of Douglas C. Barnard, Vice President, General Counsel and Secretary of the Company, dated the Closing Date, to the effect set forth on Exhibit B-2 hereto.

        (e)   The Underwriters shall have received on the Closing Date an opinion of Davis Polk & Wardwell, counsel for the Underwriters, dated the Closing Date, covering the matters referred to in clauses (ix), (x) and (xiii) and the penultimate paragraph of Exhibit B-1 hereto. With respect to the matters referred to in the penultimate paragraph of Exhibit B-1 hereto, Davis Polk & Wardwell may state that their beliefs are based on their participation in the preparation of the Registration Statement and Prospectus and any amendments or supplements thereto and review and discussion of the contents thereof, but are without independent check or verification, except as specified.

        (f)    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 Underwriters, from KPMG LLP, independent registered public accounting firm, 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 the Registration Statement and the Prospectus; provided that the letter delivered on the Closing Date shall use a "cut-off date" not earlier than the date hereof.

        (g)   The "lock-up" agreements, each substantially in the form of Exhibit A hereto, between you and certain shareholders, officers and directors of the Company and CF relating to sales and certain other dispositions of shares of Common Stock or certain other securities, delivered to you on or before the date hereof, shall be in full force and effect on the Closing Date.

        (h)   The Merger Agreement shall be in full force and effect on the Closing Date, and all conditions to the obligations of the parties thereto shall have been satisfied, other than a condition therein that all of the conditions to the transactions contemplated hereby have been satisfied or waived, and the consummation of the transactions contemplated thereby shall have occurred concurrently with the consummation of the sale of the Firm Shares.

        The several obligations of the Underwriters to purchase Additional Shares hereunder are subject to the delivery to you on the applicable Option Closing Date of such documents as you may reasonably request

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with respect to the good standing of the Company, the due authorization and issuance of the Additional Shares to be sold on such Option Closing Date and other matters related to the issuance of such Additional Shares.

        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)   To furnish to you, without charge, [    ] signed copies of the Registration Statement (including exhibits thereto) and for delivery to each other Underwriter a conformed copy of the Registration Statement (without exhibits thereto) and to furnish to you in New York City, without charge, prior to 10:00 a.m. New York City time on the business day next succeeding the date of this Agreement and during the period mentioned in Section 6(c) below, as many copies of the Prospectus and any supplements and amendments thereto or to the Registration Statement as you may reasonably request.

        (b)   Before amending or supplementing the Registration Statement or the Prospectus, to furnish to you a copy of each such proposed amendment or supplement and not to file any such proposed amendment or supplement to which you reasonably object, and to file with the Commission within the applicable period specified in Rule 424(b) under the Securities Act any prospectus required to be filed pursuant to such Rule.

        (c)   If, during such period after the first date of the public offering of the Shares as in the opinion of counsel for the Underwriters the Prospectus is required by law to be delivered in connection with sales by an Underwriter or dealer, any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Prospectus in order to make the statements therein, in the light of the circumstances when the Prospectus is delivered to a purchaser, not misleading, or if, in the opinion of counsel for the Underwriters, it is necessary to amend or supplement the Prospectus to comply with applicable law, forthwith to prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to the dealers (whose names and addresses you will furnish to the Company) to which Shares may have been sold by you on behalf of the Underwriters and to any other dealers upon request, either amendments or supplements to the Prospectus so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus, as amended or supplemented, will comply with applicable law.

        (d)   To endeavor to qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as you shall reasonably request; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not so qualified or to take any action that would subject it to material taxation or service of process in any jurisdiction where it is not so subject as of the date hereof.

        (e)   To make generally available to the Company's security holders and to you as soon as practicable an earning statement covering the twelve-month period ending             , 2006 that satisfies the provisions of Section 11(a) of the Securities Act and the rules and regulations of the Commission thereunder.

        (f)    To comply with all applicable securities and other applicable laws, rules and regulations in each jurisdiction in which the Directed Shares are offered in connection with the Directed Share Program.

        (g)   Whether or not the transactions contemplated in this Agreement are consummated or this Agreement is terminated, 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 Shares under the Securities Act and all other fees or expenses incurred by it in connection with the preparation and filing of the Registration Statement, any 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 transfer and delivery of the Shares to the Underwriters, including any transfer or other taxes payable thereon, (iii) the cost of printing or producing any Blue Sky or Legal Investment memorandum in connection with the offer and sale of the Shares under state securities laws and all expenses in connection with the qualification of the Shares for offer and sale under state securities laws as provided in Section 6(d) hereof, including filing fees and the

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reasonable fees and disbursements of counsel for the Underwriters in connection with such qualification and in connection with the Blue Sky or Legal Investment memorandum, (iv) all filing fees and the reasonable fees and disbursements of counsel to the Underwriters incurred in connection with the review and qualification of the offering of the Shares by the National Association of Securities Dealers, Inc., (v) all fees and expenses in connection with the preparation and filing of the registration statement on Form 8-A relating to the Common Stock and all costs and expenses incident to listing the Shares on the NYSE, (vi) the cost of printing certificates representing the Shares, (vii) the costs and charges of any transfer agent, registrar or depositary, (viii) 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 Shares, including, without limitation, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants 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 one-half of the cost of any aircraft chartered in connection with the road show, (ix) all fees and disbursements of counsel incurred by the Underwriters in connection with the Directed Share Program and stamp duties, similar taxes or duties or other taxes, if any, incurred by the Underwriters in connection with the Directed Share Program and (x) 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 7 entitled "Indemnity and Contribution", Section 8 entitled "Directed Share Program Indemnification" and the last paragraph of Section 10 below, the Underwriters will pay all of their costs and expenses, including fees and disbursements of their counsel, stock transfer taxes payable on resale of any of the Shares by them and any advertising expenses connected with any offers they may make.

        7.    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 Securities Exchange Act of 1934, as amended (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 in connection with defending or investigating any such action or claim) caused by any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereof, any preliminary prospectus or the Prospectus or any amendment or supplement thereto, 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 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 you expressly for use therein; provided, however, that the foregoing indemnity agreement with respect to any preliminary prospectus shall not inure to the benefit of any Underwriter from whom the person asserting any such losses, claims, damages or liabilities purchased Shares, or any person controlling such Underwriter, if a copy of the Prospectus (as then amended or supplemented if the Company shall have furnished any amendments or supplements thereto) was not sent or given by or on behalf of such Underwriter to such person, if required by law so to have been delivered, at or prior to the written confirmation of the sale of the Shares to such person, and if the Prospectus (as so amended or supplemented) would have cured the defect giving rise to such losses, claims, damages or liabilities, unless such failure is the result of noncompliance by the Company with Section 6(a) hereof.

        (b)   Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who sign the Registration Statement and each person, if any, who controls the Company within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act to the same extent as the foregoing indemnity from the Company to such Underwriter, but only with reference to information relating to such Underwriter furnished to the Company in writing by such Underwriter through you expressly for use in the Registration Statement, any preliminary prospectus, the Prospectus or any amendments or supplements thereto.

        (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 7(a) or 7(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,

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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 the reasonable fees and expenses of more than one separate firm (in addition to any local counsel) for all such indemnified parties and that all such fees and expenses shall be reimbursed as they are incurred. Such firm shall be designated in writing by Morgan Stanley, in the case of parties indemnified pursuant to Section 7(a), and by the Company, in the case of parties indemnified pursuant to Section 7(b). 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 includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such proceeding.

        (d)   To the extent the indemnification provided for in Section 7(a) or 7(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 Shares or (ii) if the allocation provided by clause 7(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 7(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 Shares shall be deemed to be in the same respective proportions as the net proceeds from the offering of the Shares (before deducting expenses) received by the Company and the total underwriting discounts and commissions received by the Underwriters, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate Public Offering Price of the Shares. 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 7 are several in proportion to the respective number of Shares 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 7 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 7(d). The amount paid or payable by an 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 7, no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Shares

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underwritten by it and distributed to the public were offered 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 7 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 7 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 by or on behalf of the Company, its officers or directors or any person controlling the Company and (iii) acceptance of and payment for any of the Shares.

        8.    Directed Share Program Indemnification.    (a) The Company agrees to indemnify and hold harmless Morgan Stanley, each person, if any, who controls Morgan Stanley within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act and each affiliate of Morgan Stanley within the meaning of Rule 405 of the Securities Act ("Morgan Stanley Entities") from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred in connection with defending or investigating any such action or claim) (i) caused by any untrue statement or alleged untrue statement of a material fact contained in any material prepared by or with the consent of the Company for distribution to Participants in connection with the Directed Share Program, 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; (ii) caused by the failure of any Participant to pay for and accept delivery of Directed Shares that the Participant has agreed to purchase; or (iii) related to, arising out of, or in connection with the Directed Share Program, other than losses, claims, damages or liabilities (or expenses relating thereto) that are finally judicially determined to have resulted from the bad faith or gross negligence of Morgan Stanley Entities.

        (b)   In case any proceeding (including any governmental investigation) shall be instituted involving any Morgan Stanley Entity in respect of which indemnity may be sought pursuant to Section 8(a), the Morgan Stanley Entity seeking indemnity shall promptly notify the Company in writing, and the Company, upon request of the Morgan Stanley Entity, shall retain counsel reasonably satisfactory to the Morgan Stanley Entity to represent the Morgan Stanley Entity and any others the Company 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 Morgan Stanley Entity shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Morgan Stanley Entity unless (i) the Company shall have agreed to the retention of such counsel or (ii) the named parties to any such proceeding (including any impleaded parties) include both the Company and the Morgan Stanley Entity and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. The Company shall not, in respect of the legal expenses of the Morgan Stanley Entities in connection with any proceeding or related proceedings in the same jurisdiction, be liable for the reasonable fees and expenses of more than one separate firm (in addition to any local counsel) for all Morgan Stanley Entities. Any such separate firm for the Morgan Stanley Entities shall be designated in writing by Morgan Stanley. The Company 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 Company agrees to indemnify the Morgan Stanley Entities from and against any loss or liability by reason of such settlement or judgment. The Company shall not, without the prior written consent of Morgan Stanley, effect any settlement of any pending or threatened proceeding in respect of which any Morgan Stanley Entity is or could have been a party and indemnity could have been sought hereunder by such Morgan Stanley Entity, unless such settlement includes an unconditional release of the Morgan Stanley Entities from all liability on claims that are the subject matter of such proceeding.

        (c)   To the extent the indemnification provided for in Section 8(a) is unavailable to a Morgan Stanley Entity or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then the Company in lieu of indemnifying the Morgan Stanley Entity thereunder, shall contribute to the amount paid or payable by the Morgan Stanley Entity as a result of such losses, claims, damages or

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liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Morgan Stanley Entities on the other hand from the offering of the Directed Shares or (ii) if the allocation provided by clause 8(c)(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(c)(i) above but also the relative fault of the Company on the one hand and of the Morgan Stanley Entities on the other hand in connection with any 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 Morgan Stanley Entities on the other hand in connection with the offering of the Directed Shares shall be deemed to be in the same respective proportions as the net proceeds from the offering of the Directed Shares (before deducting expenses) and the total underwriting discounts and commissions received by the Morgan Stanley Entities for the Directed Shares, bear to the aggregate Public Offering Price of the Directed Shares. If the loss, claim, damage or liability is caused by an untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact, the relative fault of the Company on the one hand and the Morgan Stanley Entities on the other hand shall be determined by reference to, among other things, whether the untrue or alleged untrue statement or the omission or alleged omission relates to information supplied by the Company or by the Morgan Stanley Entities and the parties' relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

        (d)   The Company and the Morgan Stanley Entities 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 Morgan Stanley Entities 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(c). The amount paid or payable by the Morgan Stanley Entities 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 the Morgan Stanley Entities in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 8, no Morgan Stanley Entity shall be required to contribute any amount in excess of the amount by which the total price at which the Directed Shares distributed to the public were offered to the public exceeds the amount of any damages that such Morgan Stanley Entity 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 Morgan Stanley Entity at law or in equity.

        (e)   The indemnity and contribution provisions contained in this Section 8 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 Morgan Stanley Entity or the Company, its officers or directors or any person controlling the Company and (iii) acceptance of and payment for any of the Directed Shares.

        9.    Termination.    The Underwriters may terminate this Agreement by notice given by you to the Company, if after the execution and delivery of this Agreement and 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 NYSE, the American 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, payment 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 your judgment, is material and adverse and which, singly or together with any other event specified in this clause (v), makes it, in your judgment, impracticable or inadvisable to proceed with the offer, sale or delivery of the Shares 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 or an Option Closing Date, as the case may be, any one or more of the Underwriters shall fail or refuse to purchase Shares that it has or they have agreed to purchase hereunder

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on such date, and the aggregate number of Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase is not more than one-tenth of the aggregate number of the Shares to be purchased on such date, the other Underwriters shall be obligated severally in the proportions that the number of Firm Shares set forth opposite their respective names in Schedule I bears to the aggregate number of Firm Shares set forth opposite the names of all such non-defaulting Underwriters, or in such other proportions as you may specify, to purchase the Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date; provided that in no event shall the number of Shares 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 number of Shares without the written consent of such Underwriter. If, on the Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Firm Shares and the aggregate number of Firm Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Firm Shares to be purchased on such date, and arrangements satisfactory to you and the Company for the purchase of such Firm Shares 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. In any such case either you 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 and in the Prospectus or in any other documents or arrangements may be effected. If, on an Option Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Additional Shares and the aggregate number of Additional Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Additional Shares to be purchased on such Option Closing Date, the non-defaulting Underwriters shall have the option to (i) terminate their obligation hereunder to purchase the Additional Shares to be sold on such Option Closing Date or (ii) purchase not less than the number of Additional Shares that such non-defaulting Underwriters would have been obligated to purchase in the absence of such default. 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.

        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 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.

        11.    Counterparts.    This Agreement may be signed in two or more counterparts, each of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument.

        12.    Applicable Law.    This Agreement shall be governed by and construed in accordance with the internal laws of the State of New York.

        13.    Headings.    The headings of the sections of this Agreement have been inserted for convenience of reference only and shall not be deemed a part of this Agreement.

        14.    Notices.    All communications hereunder shall be in writing and effective only upon receipt and if to the Underwriters shall be delivered, mailed or sent to you in care of Morgan Stanley & Co. Incorporated, 1585 Broadway, New York, New York 10036, Attention: Equity Capital Markets Syndicate Desk, and J.P. Morgan Securities Inc., 277 Park Avenue, New York, New York 10172, fax: (212) 622-8358, Attention: Henry K. Wilson; and if to the Company shall be delivered, mailed or sent to One Salem Lake Drive, Long Grove, Illinois 60027, Attention: General Counsel.

        15.    No Fiduciary Duty.    The Company acknowledges that in connection with the offering of the Shares: (a) the Underwriters have acted at arms length, are not agents of, and owe no fiduciary duties to, the Company or any other person, (b) the Underwriters owe the Company only those duties and obligations set forth in this Agreement and (c) the Underwriters may have interests that differ from those of the Company. The Company waives to the full extent permitted by applicable law any claims it may have against the Underwriters arising from an alleged breach of fiduciary duty in connection with the offering of the Shares.

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Schedule I

Exhibit A

[FORM OF LOCK-UP LETTER]

                        , 2005                        

Morgan Stanley & Co. Incorporated
J.P. Morgan Securities Inc.
Banc of America Securities LLC
Credit Suisse First Boston LLC
Harris Nesbitt Corp.
ABN AMRO Rothschild LLC
CIBC World Markets Corp.
c/o Morgan Stanley & Co. Incorporated
    1585 Broadway
    New York, NY 10036

Dear Sirs and Mesdames:

        The undersigned understands that Morgan Stanley & Co. Incorporated ("Morgan Stanley") proposes to enter into an Underwriting Agreement (the "Underwriting Agreement") with CF Industries Holdings, Inc., a Delaware corporation (the "Company"), providing for the public offering (the "Public Offering") by the several Underwriters, including Morgan Stanley (the "Underwriters"), of [            ] shares (the "Shares") of the common stock, par value $0.01 per share, of the Company (the "Common Stock").

        To induce the Underwriters that may participate in the Public Offering to continue their efforts in connection with the Public Offering, the undersigned hereby agrees that, without the prior written consent of Morgan Stanley on behalf of the Underwriters, it will not, during the period (the "Restricted Period") commencing on the date hereof and ending [180 days/one year]¹ after the date of the final prospectus relating to the Public Offering (the "Prospectus"), (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock, or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise. The foregoing sentence shall not apply to (a) transactions relating to shares of Common Stock or other securities acquired in open market transactions after the completion of the Public Offering, provided that no filing under Section 16(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act") shall be required or shall be voluntarily made in connection with subsequent sales of Common Stock or other securities acquired in such open market transactions, (b) the establishment of a trading plan pursuant to Rule 10b-5 under the Exchange Act, provided that no sales or other transfers may occur under such plan during the Restricted Period, (c) transfers of shares of Common Stock or any security convertible into Common Stock as a bona fide gift, (d) transfers of shares of Common Stock or any security convertible into Common Stock to a trust where the beneficiaries of the trust are drawn solely from a group consisting of the undersigned and immediate family members of the undersigned, (e) if the undersigned is a corporation, limited partnership or limited liability company, transfers of shares of Common Stock or any security convertible into Common Stock to

1

One year for existing stockholders of CF Industries, Inc. 180 days for directors and officers.

A-1

stockholders, limited partners, members, subsidiaries or other affiliates of the undersigned, (f) transfers of shares of Common Stock constituting director compensation by a director of the Company to such director's employer or former employer or (g) transfers of shares of Common Stock or any security convertible into Common Stock by a former owner of CF Industries, Inc., to another former owner of CF Industries, Inc. after the date that is 180 days after the date of the Prospectus; provided that in the case of any transfer pursuant to clause (c), (d), (e), (f) or (g), (i) each donee, trust or transferee shall sign and deliver a lock-up letter substantially in the form of this letter (if it has not already done so) and (ii) no filing (other than a Form 5) under Section 16(a) of the Exchange Act, reporting a reduction in beneficial ownership of shares of Common Stock, shall be required or shall be voluntarily made during the Restricted Period. "Immediate family member" of a person means the spouse, lineal descendants, father, mother, brother, sister, father-in-law, mother-in-law, brother-in-law and sister-in-law of such person.

        In addition, the undersigned agrees that, without the prior written consent of Morgan Stanley on behalf of the Underwriters, it will not, during the Restricted Period, make any demand for or exercise any right with respect to, the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock. The undersigned also agrees and consents to the entry of stop transfer instructions with the Company's transfer agent and registrar against the transfer of the undersigned's shares of Common Stock except in compliance with the foregoing restrictions.

        If:

        (1)   during the last 17 days of the Restricted Period the Company issues an earnings release or material news or a material event relating to the Company occurs; or

        (2)   prior to the expiration of the Restricted Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the Restricted Period;

the restrictions imposed by this agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

        The undersigned shall not engage in any transaction that may be restricted by this agreement during the 34-day period beginning on the last day of the initial Restricted Period unless the undersigned requests and receives prior written confirmation from the Company or Morgan Stanley that the restrictions imposed by this agreement have expired.

        The undersigned understands that the Company and the Underwriters are relying upon this agreement in proceeding toward consummation of the Public Offering. The undersigned further understands that this agreement is irrevocable and shall be binding upon the undersigned's heirs, legal representatives, successors and assigns.

        Whether or not the Public Offering actually occurs depends on a number of factors, including market conditions. Any Public Offering will only be made pursuant to an Underwriting Agreement, the terms of which are subject to negotiation between the Company and the Underwriters. This letter shall lapse and become null and void if the first closing of the Public Offering shall not have occurred on or prior to September 30, 2005.

A-2

QuickLinks

Exhibit 1.1

Exhibit A