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As filed with the Securities and Exchange Commission on January 31, 2002.

Registration No. 333-            



SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549


FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933


AMEREN CORPORATION

(Exact name of registrant as specified in its charter)

Missouri   43-1723446
(State or other jurisdiction of
incorporation or Organization)
  (I.R.S. Employer
Identification No.)

1901 Chouteau Avenue,
St. Louis, Missouri 63103
(314) 621-3222
(Address, including zip code, and telephone number, including
area code, of registrant's principal executive offices)

WARNER L. BAXTER
Senior Vice President, Finance

STEVEN R. SULLIVAN
Vice President, General Counsel and Secretary
1901 Chouteau Avenue
St. Louis, Missouri 63103
(314) 621-3222
(Name, address, including zip code, and telephone number,
including area code, of agents for service)

Approximate date of commencement of proposed sale to the public:  From time to time after the effective date of the registration statement as determined by market conditions and other factors.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. / /

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. /x/

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. / /

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. / /

If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box. / /

CALCULATION OF REGISTRATION FEE


Title of each class of securities to be registered
  Proposed maximum aggregate offering price(1)
  Amount of registration fee

Senior Debt Securities        

Subordinated Debt Securities        

Trust Preferred Securities and Related Guarantees(2)        

Common Stock, $.01 par value (including associated preferred share purchase rights)        

Stock Purchase Contracts        

Stock Purchase Units(3)        

  Total   $1,000,000,000   $92,000

(1)
There are being registered hereunder such presently indeterminate principal amount or number of Senior Debt Securities, Subordinated Debt Securities, Trust Preferred Securities, shares of Common Stock, Stock Purchase Contracts and Stock Purchase Units with an aggregate initial offering price not to exceed $1,000,000,000. Debt Securities also may be issued to a trust in connection with the issuance and sale of Trust Preferred Securities and later distributed upon dissolution and distribution of the assets thereof, which would include such Debt Securities for which no separate consideration will be received. An indeterminate number of shares of Common Stock may also be issued upon settlement of the Stock Purchase Contracts, Stock Purchase Units or warrants. Pursuant to Rule 457(o) under the Securities Act of 1933, and General Instruction II.D. of Form S-3, which permits the registration fee to be calculated on the basis of the maximum aggregate offering price of all the securities listed, the table does not specify by each class information as to the amount to be registered, proposed maximum offering price per unit or proposed maximum aggregate offering price.
(2)
Includes the obligations of Ameren Corporation under the respective trust agreements, the applicable indenture, the related series of Debt Securities and the respective Guarantees, which include Ameren Corporation's covenant to pay any indebtedness, expenses or liabilities of the trusts (other than obligations pursuant to the terms of the Trust Preferred Securities or other similar interests), all as described in this registration statement. No separate consideration will be received for the Guarantees and, pursuant to Rule 457(n) under the Securities Act of 1933, no separate fee is payable in respect thereof.
(3)
Each Stock Purchase Unit consists of (a) a Stock Purchase Contract, under which the holder, upon settlement, will purchase an indeterminate number of shares of Common Stock and (b) a beneficial interest in either Senior Debt Securities or Subordinated Debt Securities, Trust Preferred Securities issued by trusts or debt obligations of third parties, including U.S. Treasury securities, purchased with the proceeds from the sale of the Stock Purchase Units. Each beneficial interest will be pledged to secure the obligation of such holder to purchase such shares of Common Stock. No separate consideration will be received for the Stock Purchase Contracts or the related beneficial interests.

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.




The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED JANUARY 31, 2002

PROSPECTUS

         LOGO


AMEREN CORPORATION


$1,000,000,000


Senior Debt Securities
Subordinated Debt Securities
Trust Preferred Securities and Related Guarantees
Common Stock
Stock Purchase Contracts
Stock Purchase Units


        Ameren Corporation intends to offer these securities from time to time in one or more series with an aggregate offering price not to exceed $1,000,000,000. This prospectus provides you with a general description of these securities. We will provide specific information about the offering and the terms of these securities in supplements to this prospectus. The supplements may also add, update or change information contained in this prospectus. You should read this prospectus and the supplements carefully before investing. This prospectus may not be used to sell any of these securities unless accompanied by a prospectus supplement.

        The common stock of Ameren Corporation is listed on the New York Stock Exchange under the symbol "AEE".

        Our principal executive offices are located at 1901 Chouteau Avenue, St. Louis, Missouri 63103 and our telephone number is (314) 621-3222.


        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.


        We may offer these securities directly or through underwriters, agents or dealers. Each prospectus supplement will provide the terms of the plan of distribution relating to each series of securities. See "Plan of Distribution."

The date of this prospectus is                        , 2002.



ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, which we refer to as the SEC, utilizing a "shelf" registration, or continuous offering, process. Under this shelf registration process, we may issue and sell any combination of the securities described in this prospectus in one or more offerings with a maximum aggregate offering price of up to $1,000,000,000. We may offer any of the following securities: senior debt securities or subordinated debt securities, each of which may be convertible into our common stock, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units. We may also offer warrants to purchase debt securities or shares of our common stock. If we issue and sell trust preferred securities, we will amend the registration statement of which this prospectus is a part to include each trust issuer as a registrant for purposes of issuing and selling trust preferred securities of that trust.

        This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering. Any prospectus supplement may also add, update or change information contained in this prospectus. If there is any inconsistency between the information in this prospectus and the prospectus supplement, you should rely on the information in the prospectus supplement. The registration statement we filed with the SEC includes exhibits that provide more detail on descriptions of the matters discussed in this prospectus. You should read this prospectus and the related exhibits filed with the SEC and any prospectus supplement together with additional information described under the heading "Where You Can Find More Information."

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FORWARD-LOOKING STATEMENTS

        Statements made in this prospectus, any accompanying prospectus supplement and the documents described under "Where You Can Find More Information," which are not based on historical facts, are "forward-looking" and, accordingly, involve risks and uncertainties that could cause actual results to differ materially from those discussed. Although such "forward-looking" statements have been made in good faith and are based on reasonable assumptions, there is no assurance that the expected results will be achieved. These statements include, without limitation, statements as to future expectations, beliefs, plans, strategies, objectives, events, conditions and financial performance. In connection with the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, we are providing this cautionary statement to identify important factors that could cause actual results to differ materially from those anticipated. The following factors, in addition to those discussed elsewhere in this prospectus, any accompanying prospectus supplement and the documents described under "Where You Can Find More Information," could cause results to differ materially from management expectations as suggested by such "forward-looking" statements:

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        Given these uncertainties, you should not place undue reliance on these forward-looking statements. Except to the extent required by the federal securities laws, we undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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AMEREN CORPORATION

        Ameren is a public utility holding company registered under the Public Utility Holding Company Act of 1935 and does not own or operate any significant assets other than the stock of its subsidiaries. Ameren was incorporated in Missouri on August 7, 1995. On December 31, 1997, following the receipt of all required approvals, CIPSCO Incorporated and Union Electric Company, or AmerenUE, combined with the result that the common shareholders of CIPSCO and AmerenUE became the common shareholders of Ameren, and Ameren became the owner of 100% of the common stock of AmerenUE and CIPSCO's subsidiaries, Central Illinois Public Service Company, or AmerenCIPS, and CIPSCO Investment Company.

        Ameren's primary operating subsidiaries are AmerenCIPS, AmerenUE and AmerenEnergy Generating Company, which collectively are engaged principally in the generation, transmission, distribution and sale of electric energy and the purchase, distribution, transportation and sale of natural gas. AmerenCIPS, a first tier subsidiary, is an Illinois corporation organized in 1902. It supplies electric and gas utility service to territories in central and southern Illinois having an estimated population of 820,000 within an area of approximately 20,000 square miles. AmerenCIPS supplies electric service to about 325,000 customers and natural gas service to about 175,000 customers. AmerenUE, also a first tier subsidiary, was incorporated in Missouri in 1922 and is successor to a number of companies, the oldest of which was organized in 1881. It is the largest electric utility in the State of Missouri and supplies electric and gas service in territories in Missouri and Illinois having an estimated population of 2.6 million within an area of approximately 24,500 square miles, including the greater St. Louis area. AmerenUE supplies electric service to about 1.2 million customers and natural gas service to about 125,000 customers. AmerenEnergy Generating Company, an indirect wholly owned nonregulated electric generating subsidiary of AmerenEnergy Resources Company, was incorporated in Illinois in March 2000 in conjunction with the Illinois Electric Service Customer Choice and Rate Relief Law of 1997. This law provides for electric utility restructuring and introduces competition into the supply of electric energy at retail in Illinois. AmerenEnergy Generating Company, a wholesale electricity supplier, commenced operations on May 1, 2000 when AmerenCIPS transferred all of its net electric generating assets to it at net book value, consisting of certain generating facilities, all related fuel, supply, transportation, maintenance and labor agreements, approximately 45% of AmerenCIPS' employees, and some other related rights, assets and liabilities.

        Ameren, directly or indirectly, also owns all of the common stock of the following principal subsidiary companies:

In addition, Ameren indirectly owns 60% of the common stock of Electric Energy, Inc., which owns and/or operates electric generation and transmission facilities in Illinois that supply electric power primarily to a uranium enrichment plant located in Paducah, Kentucky.

        In this prospectus, "Ameren," "we," "us" and "our", as well as correlative terms, refer to Ameren Corporation and, unless the context otherwise indicates, does not include our subsidiaries.

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WHERE YOU CAN FIND MORE INFORMATION

        We have filed a registration statement on Form S-3 with the SEC under the Securities Act of 1933. This prospectus is part of the registration statement, but the registration statement also contains or incorporates by reference additional information and exhibits. We are subject to the informational requirements of the Securities Exchange Act of 1934 and, therefore, we file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy the registration statement and any document that we file with the SEC at the SEC's public reference room at 450 Fifth Street, N.W., Washington, D.C. 20549. You can call the SEC's toll-free telephone number at 1-800-SEC-0330 for further information on the public reference room. The SEC maintains a web site at http://www.sec.gov that contains reports, proxy and information statements and other information regarding companies, such as us, that file documents with the SEC electronically. The documents can be found by searching the EDGAR Archives of the SEC electronically.

        The SEC allows us to "incorporate by reference" the information that we file with the SEC which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus and you should read it with the same care. Later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the following documents previously filed with the SEC:

        We are also incorporating by reference all additional documents that we file with the SEC under Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934 between the date of the initial filing of the registration statement of which this prospectus is a part and the effectiveness of the registration statement, as well as between the date of this prospectus and the time that all of the securities registered are sold.

        You may request a free copy of these filings by writing or telephoning us at the following address:

        Ameren Corporation
        Attention: Secretary's Department
        P.O. Box 149
        St. Louis, Missouri 63166
        Telephone: (314) 621-3222

        You should rely only on the information incorporated by reference or provided in this prospectus or any supplement. We have not authorized anyone else to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not making an offer to sell these securities in any state where the offer or sale is not permitted. You should not assume that the information in this prospectus or any supplement is accurate as of any date other than the date on the front of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

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RATIOS OF EARNINGS TO FIXED CHARGES

        The ratio of earnings to fixed charges is computed by dividing earnings by fixed charges before income taxes. For the purposes of such computations:


 
  Year Ended December 31,
   
 
  Nine Months Ended
September 30, 2001

 
  1996(1)
  1997(1)
  1998
  1999
  2000
Ratio of Earnings to Fixed Charges   3.81   3.91   4.06   4.20   4.59   5.19

(1)
The ratio of earnings to fixed charges for the years ended December 31, 1996 and 1997 reflect the accounting for the merger of CIPSCO Incorporated and Union Electric Company, which was completed on December 31, 1997, as a pooling of interests and are presented as if the two companies were combined as of the earliest period presented.


USE OF PROCEEDS

        Unless we state otherwise in any prospectus supplement, we may use the net proceeds we receive from any sale of the offered securities:

        The prospectus supplement relating to a particular offering of securities by us will identify the use of proceeds for that offering.

        The proceeds from the sale of trust preferred securities by a trust will be invested in debt securities issued by us. Except as we may otherwise describe in the related prospectus supplement, we expect to use the net proceeds from the sale of such debt securities to the applicable trust for the above purposes.

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DESCRIPTION OF DEBT SECURITIES

General

        The senior debt securities and the subordinated debt securities, which we refer to collectively as the debt securities, will represent unsecured obligations of Ameren Corporation. We may issue one or more series of debt securities directly to the public, to a trust or as part of a stock purchase unit from time to time. We expect that each series of senior debt securities or subordinated debt securities will be issued as a new series of debt securities under one of two separate indentures, as each may be amended or supplemented from time to time. We will issue the senior debt securities in one or more series under a senior indenture dated as of December 1, 2001 between us and The Bank of New York, as trustee. We will issue the subordinated debt securities in one or more series under a subordinated indenture between us and a trustee. The senior indenture, the form of the subordinated indenture and the form of supplemental indenture or other instrument establishing the debt securities of a particular series are filed as exhibits to, or will be subsequently incorporated by reference in, the registration statement of which this prospectus is a part. Each indenture will be qualified under the Trust Indenture Act of 1939. The following summaries of certain provisions of the senior indenture, the subordinated indenture and the applicable debt securities do not purport to be complete and are subject to, and qualified in their entirety by, all of the provisions of the senior indenture or the subordinated indenture, as the case may be, and the applicable debt securities. We may also sell hybrid or novel securities now existing or developed in the future that combine certain features of the debt securities and other securities described in this prospectus. We may be required to obtain the approval of the SEC under the Public Utility Holding Company Act of 1935 before we can issue and sell certain of these securities.

        There is no requirement under the senior indenture, nor will there be any such requirement under, the subordinated indenture that our future issuances of debt securities be issued exclusively under either indenture, and we will be free to employ other indentures or documentation, containing provisions different from those included in either indenture or applicable to one or more issuances of senior debt securities or subordinated debt securities, as the case may be, in connection with future issuances of other debt securities. The senior indenture provides and the subordinated indenture will provide that the applicable debt securities will be issued in one or more series, may be issued at various times, may have differing maturity dates and may bear interest at differing rates. We need not issue all debt securities of one series at the same time and, unless otherwise provided, we may reopen a series, without the consent of the holders of the senior debt securities or the subordinated debt securities of that series, as the case may be, for issuances of additional senior debt securities or subordinated debt securities of that series, as applicable. Unless otherwise described in the applicable prospectus supplement, neither indenture described above limits or will limit the aggregate amount of debt, including secured debt, we or our subsidiaries may incur.

Ranking

        The senior debt securities will be our direct unsecured general obligations and will rank equally with all of our other unsecured and unsubordinated debt. As of December 31, 2001, our aggregate outstanding debt that would have ranked equally with the senior debt securities was approximately $558 million, including $150 million of senior debt securities outstanding under the senior indenture. In January 2002, we issued an additional $100 million of senior debt securities under the senior indenture, the net proceeds of which were used to repay a portion of our short-term debt. In addition, we have been granted authority by the SEC to issue up to $1.5 billion of guarantees for the benefit of our non-utility subsidiaries and expect to have such guarantees outstanding from time to time in various aggregate amounts. The subordinated debt securities will be our direct unsecured general obligations and will be junior in right of payment to our Senior Indebtedness, as described under the heading "—Subordination of Subordinated Debt Securities."

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        Ameren is a holding company that derives substantially all of its income from its operating subsidiaries. As a result, our cash flows and consequent ability to service our debt, including the debt securities, are dependent upon the earnings of our subsidiaries and distribution of those earnings to us and other payments or distributions of funds by our subsidiaries to us, including payments of principal and interest under intercompany indebtedness. Our operating subsidiaries are separate and distinct legal entities and will have no obligation, contingent or otherwise, to pay any dividends or make any other distributions (except for payments required pursuant to the terms of intercompany indebtedness) to us or to otherwise pay amounts due with respect to the debt securities or to make specific funds available for such payments. Various financing arrangements, charter provisions and regulatory requirements may impose certain restrictions on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans or advances. Furthermore, except to the extent we have a priority or equal claim against our subsidiaries as a creditor, the debt securities will be effectively subordinated to debt and preferred stock at the subsidiary level because, as the common shareholder of our subsidiaries, we will be subject to the prior claims of creditors of our subsidiaries. As of December 31, 2001, our subsidiaries had approximately $3.3 billion of aggregate outstanding debt and preferred stock.

Provisions of a Particular Series

        The prospectus supplement applicable to each issuance of debt securities will specify, among other things:

        Unless otherwise indicated in the applicable prospectus supplement, there will be no provisions in either indenture or the related debt securities that require us to redeem, or permit the holders to cause a redemption of, those debt securities or that otherwise protect the holders in the event that we incur substantial additional indebtedness, whether or not in connection with a change in control, or grant security for other of our indebtedness.

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Subordination of Subordinated Debt Securities

        The subordinated debt securities will be subordinate and junior in right of payment to all of our Senior Indebtedness, as defined below.

        No payment of principal of (including redemption and sinking fund payments), premium, if any, or interest on, the subordinated debt securities may be made if any Senior Indebtedness is not paid when due, any applicable grace period with respect to such default has ended and such default has not been cured or waived, or the maturity of any Senior Indebtedness has been accelerated because of a default and such acceleration has not been rescinded or annulled.

        Upon any distribution of our assets to creditors upon any dissolution, winding-up, liquidation or reorganization, whether voluntary or involuntary, or in bankruptcy, insolvency, receivership or other proceedings, all principal of, and premium, if any, and interest due or to become due on, all Senior Indebtedness must be paid in full before the holders of the subordinated debt securities are entitled to receive or retain any payment. The rights of the holders of the subordinated debt securities will be subrogated to the rights of the holders of Senior Indebtedness to receive payments or distributions applicable to Senior Indebtedness until all amounts owing on the subordinated debt securities are paid in full. If provided in the applicable prospectus supplement, limited subordination periods may apply in the event of non-payment defaults relating to Senior Indebtedness in situations where there has not been an acceleration of Senior Indebtedness.

        As defined in the subordinated indenture, the term "Senior Indebtedness" means:



        The subordinated indenture will not limit the aggregate amount of Senior Indebtedness that we may issue. As of December 31, 2001, our outstanding Senior Indebtedness aggregated approximately $558 million.

Registration, Transfer and Exchange

        Unless otherwise indicated in the applicable prospectus supplement, each series of debt securities, other than debt securities issued to a trust, will initially be issued in the form of one or more global securities, in registered form, without coupons, as described under "Book-Entry System." The global securities will be registered in the name of The Depository Trust Company, as depository, or its nominee, and deposited with, or on behalf of, the depository. Except in the circumstances described under "Book-Entry System," owners of beneficial interests in a global security will not be entitled to have debt securities registered in their names, will not receive or be entitled to receive physical delivery of any debt securities and will not be considered the registered holders thereof under the applicable indenture.

        Debt securities of any series will be exchangeable for other debt securities of the same series of any authorized denominations and of a like aggregate principal amount and tenor. Subject to the terms of the applicable indenture and the limitations applicable to global securities, debt securities may be presented for exchange or registration of transfer—duly endorsed or accompanied by a duly executed

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instrument of transfer—at the office of any transfer agent we may designate for such purpose, without service charge but upon payment of any taxes and other governmental charges as described in the applicable indenture.

        Unless otherwise indicated in the applicable prospectus supplement, the transfer agent will be the trustee under the applicable indenture. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

Payment and Paying Agents

        Principal of and interest and premium, if any, on debt securities issued in the form of global securities will be paid in the manner described under "Book-Entry System."

        Unless otherwise indicated in the applicable prospectus supplement, the principal of and any premium and interest on debt securities of a particular series in the form of certificated securities will be payable at the office of the applicable trustee or at the authorized office of any paying agent or paying agents upon presentation and surrender of such debt securities. We may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts, except that we will be required to maintain a paying agent in each place of payment for the debt securities of a particular series. Unless otherwise indicated in the applicable prospectus supplement, interest on the debt securities of a particular series, other than interest at maturity, that are in the form of certificated securities will be paid by check payable in clearinghouse funds mailed to the person entitled thereto at such person's address as it appears on the register for such debt securities maintained by the applicable trustee; provided, however, a holder of certificated securities in the aggregate principal amount of $10,000,000 or more will be entitled to receive payments of interest by wire transfer of immediately available funds to a bank within the continental United States if the trustee has received appropriate wire transfer instructions on or prior to the applicable regular record date for such interest payment date.

        All monies we pay to a trustee or a paying agent for the payment of the principal of, and premium or interest, if any, on, any debt security which remain unclaimed at the end of two years after such principal, premium or interest shall have become due and payable will be repaid to us, and the holder of such debt security thereafter may look only to us for payment thereof.

Redemption

        Any terms for the optional or mandatory redemption of the debt securities will be set forth in the applicable prospectus supplement. Unless otherwise indicated in the applicable prospectus supplement, debt securities will be redeemable by us only upon notice by mail not less than 30 nor more than 60 days prior to the date fixed for redemption, and, if less than all the debt securities of a series are to be redeemed, the particular debt securities to be redeemed will be selected by such method as shall be provided for any particular series, or in the absence of any such provision, by the trustee in such manner as it shall deem fair and appropriate.

        Any notice of redemption at our option may state that such redemption will be conditional upon receipt by the trustee or the paying agent or agents, on or prior to the dated fixed for such redemption, of money sufficient to pay the principal of and premium, if any, and interest on, such debt securities and that if such money has not been so received, such notice will be of no force and effect and we will not be required to redeem such debt securities.

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Events of Default

        Each of the following will constitute an event of default under the senior indenture or the subordinated indenture with respect to senior debt securities or subordinated debt securities, as the case may be, of any series:

No event of default with respect to the debt securities of a particular series necessarily constitutes an event of default with respect to the debt securities of any other series issued under the applicable indenture. If provided in the applicable prospectus supplement, an event of default similar to the event of default described in the fourth bullet above may be applicable to a series of subordinated debt securities.

        If an event of default with respect to any series of debt securities occurs and is continuing, then either the trustee for such series or the holders of a majority in aggregate principal amount of the outstanding debt securities of such series, by notice in writing, may declare the principal amount of and interest on all of the debt securities of such series to be due and payable immediately; provided, however, that if an event of default occurs and is continuing with respect to more than one series of debt securities under a particular indenture, the trustee for such series or the holders of a majority in aggregate principal amount of the outstanding debt securities of all such series, considered as one class, may make such declaration of acceleration and not the holders of the debt securities of any one of such series.

        At any time after an acceleration with respect to the debt securities of any series has been declared, but before a judgment or decree for the payment of the money due has been obtained, the event or events of default giving rise to such acceleration will be waived, and the acceleration will be rescinded and annulled, if

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However, no such waiver or rescission and annulment shall extend to or shall affect any subsequent default or impair any related right.

        Subject to the provisions of the applicable indenture relating to the duties of the trustee in case an event of default shall occur and be continuing, the trustee generally will be under no obligation to exercise any of its rights or powers under the applicable indenture at the request or direction of any of the holders unless such holders have offered to the trustee reasonable security or indemnity. Subject to such provisions for the indemnification of the trustee and certain other limitations contained in the applicable indenture, the holders of a majority in aggregate principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or of exercising any trust or power conferred on the trustee, with respect to the debt securities of that series; provided, however, that if an event of default occurs and is continuing with respect to more than one series of debt securities, the holders of a majority in aggregate principal amount of the outstanding debt securities of all those series, considered as one class, will have the right to make such direction, and not the holders of the debt securities of any one series. Any direction provided by the holders shall not be in conflict with any rule of law or with the senior indenture or the subordinated indenture, as the case may be, and will not involve the trustee in personal liability in circumstances where reasonable indemnity would not, in the trustee's sole discretion, be adequate and the trustee may take any other action it deems proper that is not inconsistent with such direction.

        The holders of a majority in aggregate principal amount of the outstanding debt securities of any series may waive any past default under the applicable indenture on behalf of all holders of debt securities of that series with respect to the debt securities of that series, except a default in the payment of principal of or any premium or interest on such debt securities. No holder of debt securities of any series may institute any proceeding with respect to the applicable indenture, or for the appointment of a receiver or a trustee, or for any other remedy, unless such holder has previously given to the trustee for such series written notice of a continuing event of default with respect to the debt securities of such series, the holders of a majority in aggregate principal amount of the outstanding debt securities of all series in respect of which an event of default has occurred and is continuing, considered as one class, have made written request to the trustee for such series to institute such proceeding and have offered reasonable indemnity, and the trustee for such series has failed to institute such proceeding within 60 days after such notice, request and offer. Furthermore, no holder of debt securities of any series will be entitled to institute any such action if and to the extent that such action would disturb or prejudice the rights of other holders of those debt securities.

        Notwithstanding the foregoing, each holder of debt securities of any series has the right, which is absolute and unconditional, to receive payment of the principal of and premium and interest, if any, on such debt securities when due and to institute suit for the enforcement of any such payment, and such rights may not be impaired without the consent of that holder of debt securities.

        The trustee, within 90 days after it receives notice of the occurrence of a default with respect to the debt securities of any series, is required to give the holders of the debt securities of that series notice of such default, unless cured or waived, but, except in the case of default in the payment of principal of, or premium, if any, or interest on, the debt securities of that series, the trustee may withhold such notice if it determines in good faith that it is in the interest of such holders to do so. We will be required to deliver to the trustees for the debt securities each year a certificate as to whether or

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not, to the knowledge of the officers signing such certificate, we are in compliance with all conditions and covenants under the applicable indenture, determined without regard to any period of grace or requirement of notice under such indenture.

Modification

        Without the consent of any holder of debt securities, the trustee for such debt securities and we may enter into one or more supplemental indentures for any of the following purposes:



        Except as provided above, the consent of the holders of a majority in aggregate principal amount of either the senior debt securities or the subordinated debt securities, as the case may be, of all series then outstanding, considered as one class, is required for the purpose of adding any provisions to, or changing in any manner, or eliminating any of the provisions of, the applicable indenture pursuant to one or more supplemental indentures or of modifying or waiving in any manner the rights of the holders of the applicable debt securities; provided, however, that if less than all of the series of senior debt securities or subordinated debt securities outstanding, as the case may be, are directly affected by a proposed supplemental indenture, then the consent only of the holders of a majority in aggregate principal amount of the outstanding applicable debt securities of all series so directly affected, considered as one class, will be required.

        Notwithstanding the foregoing, no such amendment or modification may, without the consent of each holder of outstanding debt securities affected thereby:

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        A supplemental indenture which changes or eliminates any covenant or other provision of the applicable indenture which has expressly been included solely for the benefit of one or more series of debt securities, or which modifies the rights of the holders of debt securities of such series with respect to such covenant or provision, will be deemed not to affect the rights under the applicable indenture of the holders of the debt securities of any other series.

Defeasance and Discharge

        Unless the applicable prospectus supplement states otherwise, we may elect either:

        In the case of either (1) or (2), we are required to deposit, in trust, with the applicable trustee money or U.S. government obligations, which through the payment of interest on those obligations and principal of those obligations in accordance with their terms will provide money, in an amount sufficient, without reinvestment, to pay all the principal of, premium, if any, and interest on the debt securities of such series on the dates payments are due (which may include one or more redemption dates designated by us). This trust may only be established if, among other things, (A) no event of default or event which with the giving of notice or lapse of time, or both, would become an event of default under the applicable indenture has occurred and is continuing on the date of the deposit, (B) the deposit will not cause the trustee to have any conflicting interest with respect to our other securities and (C) we have delivered an opinion of counsel to the effect that the holders will not recognize income, gain or loss for federal income tax purposes (and, in the case of paragraph (1) above, such opinion of counsel is based on a ruling of the Internal Revenue Service or other change in applicable federal income tax law) as a result of the deposit or defeasance and will be subject to federal income tax in the same amounts, in the same manner and at the same times as if the deposit and defeasance had not occurred.

        We may exercise our defeasance option under paragraph (1) with respect to debt securities of any series notwithstanding our prior exercise of our covenant defeasance option under paragraph (2). If we exercise our defeasance option for debt securities of any series, payment of the debt securities of such series may not be accelerated because of a subsequent event of default. If we exercise our covenant defeasance option for debt securities of any series, payment of the debt securities of such series may not be accelerated by reference to a subsequent breach of any of the covenants noted under clause (2) in the preceding paragraph. In the event we omit to comply with our remaining obligations with respect to the debt securities of any series under the applicable indenture after exercising our covenant defeasance option and the debt securities of such series are declared due and payable because of the subsequent occurrence of any event of default, the amount of money and U.S. government obligations on deposit with the trustee may be insufficient to pay amounts due on the debt securities of such series

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at the time of the acceleration resulting from that event of default. However, we will remain liable for those payments.

Consolidation, Merger and Sale or Disposition of Assets

        We have agreed not to consolidate with or merge into any other corporation or sell or otherwise dispose of our properties as or substantially as an entirety to any person, unless:

        Upon any such consolidation, merger, sale, transfer or other disposition of our properties as or substantially as an entirety, the successor corporation formed by such consolidation or into which we are merged or the person to which such sale, transfer or other disposition is made shall succeed to, and be substituted for, and may exercise every right and power of, us under the applicable indenture with the same effect as if such successor corporation or person had been named as us therein, and we will be released from all obligations under the applicable indenture.

        Certain of the indentures for debt securities issued or to be issued by AmerenUE and AmerenCIPS provide that the conveyance or other transfer by either company of all or any portion of its facilities for the generation of electric energy, all of its facilities for the transmission of electric energy, or all of its facilities for the distribution of natural gas, in each case considered alone or in any combination with properties described in any other clause, shall in no event be deemed to constitute a conveyance or other transfer of all of its properties, as or substantially as an entirety.

Resignation or Removal of Trustee

        The trustee may resign at any time upon written notice to us specifying the day upon which the resignation is to take effect and such resignation will take effect immediately upon the later of the appointment of a successor trustee and such specified day. The trustee may be removed at any time with respect to debt securities of any series by an instrument or concurrent instruments in writing filed with the trustee and signed by the holders, or their attorneys-in-fact, of a majority in aggregate principal amount of that series of debt securities then outstanding. In addition, so long as no event of default or event which, with the giving of notice or lapse of time or both, would become an event of default has occurred and is continuing, we may remove the trustee upon notice to the holder of each debt security outstanding and the trustee, and appointment of a successor trustee.

Concerning the Trustee for Senior Debt Securities

        We and our affiliates maintain corporate trust and other normal banking relationships with The Bank of New York, the trustee under the senior indenture. Each indenture provides that our obligations to compensate the trustee and reimburse the trustee for expenses, disbursements and advances will be secured by a lien prior to that of the applicable debt securities upon the property and funds held or collected by the trustee as such.

Governing Law

        Each of the senior indenture and the subordinated indenture and the related debt securities will be governed by New York law.

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DESCRIPTION OF TRUST PREFERRED SECURITIES

        This prospectus describes certain general terms of the trust preferred securities. The trust preferred securities will be issued by one or more statutory business trusts which we will form under Delaware law prior to such issuance. At that time, we intend to amend the registration statement of which this prospectus is a part to include each trust issuer as a registrant for purposes of issuing and selling trust preferred securities of that trust. At the time trust preferred securities are to be issued, the original trust agreement will be amended and restated, to be effective at the time of such issuance. The form of amended and restated trust agreement is filed as an exhibit to the registration statement of which this prospectus is a part. The amended and restated trust agreement, which we will refer to in this prospectus as the "trust agreement," for each trust will be qualified as an indenture under the Trust Indenture Act of 1939. You should read the form of amended and restated trust agreement for provisions that may be important to you. When we offer to sell a particular series of trust preferred securities, we will describe the specific terms of that series in a prospectus supplement. The trust preferred securities will be issued pursuant to the related trust agreements, which we have summarized below. This summary is not complete.

General

        Each trust will exist for the exclusive purposes of:


        Our debt securities will be the sole assets of each trust, and our payments under the debt securities will be the sole revenue of each trust. No separate financial statements of any trust will be included in this prospectus. We consider that these financial statements would not be material to holders of the trust preferred securities because no trust would have any independent operations and the only purposes of each trust are those described above. We do not expect that any trust will be filing annual, quarterly or special reports with the SEC. The principal place of business of each trust will be c/o Ameren Corporation, 1901 Chouteau Avenue, St. Louis, Missouri 63103.

        Each trust will exist until terminated as provided in its trust agreement. The administrators and trustees of each trust will be:

        The trust agreement will authorize the administrators to issue two classes of trust securities: trust preferred securities and trust common securities. We will own all of the trust common securities issued by each trust, which will rank equally in right of payment with the trust preferred securities issued by the respective trust. However, if an event of default occurs and is continuing under the trust agreement, rights of the holders of the trust common securities to payment for distributions and otherwise will be

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subordinated to the rights of the holders of the trust preferred securities. We will acquire trust common securities of each trust in a total liquidation amount of approximately three percent of the total capital of the trust.

        Proceeds from the sale of both the trust preferred securities and the trust common securities issued by each trust will be used to purchase our debt securities, which will be held in trust by the property trustee for the benefit of the holders of the trust securities issued by the respective trust. We will guarantee the payments of distributions and payments of redemption or liquidation with respect to the trust preferred securities issued by each trust, but only to the extent the respective trust has funds available to make those payments and has not made the payments. See "Description of Guarantees" below.

        Each guarantee, when taken together with our obligations under the related debt securities, the related indenture and the related trust agreement, will provide a full and unconditional guarantee of amounts due on the trust preferred securities issued by the respective trust. The trust preferred securities will have the terms, including distributions, redemption, voting, liquidation rights and other rights or restrictions that will be described in the related trust agreement or made part of it by the Trust Indenture Act or the Delaware Business Trust Act.

Provisions of a Particular Series

        Each trust may issue only one series of trust preferred securities. The applicable prospectus supplement will set forth the principal terms of the trust preferred securities that will be offered, including:

        Terms of the trust preferred securities issued by each trust will mirror the terms of the debt securities held by the respective trust. In other words, the interest rate and interest and other payment dates of each series of debt securities issued to a trust will correspond to the rate at which distributions will be paid and the distribution and other payment dates of the trust preferred securities of that trust. The prospectus supplement will also set forth whether the debt securities to be issued to a trust will be senior debt securities or subordinated debt securities.

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Distributions

        The trust preferred securities represent preferred, undivided, beneficial interests in the assets of the respective trust. The applicable prospectus supplement will state the annual rate, as a percentage of the liquidation amount, at which distributions on each trust preferred security will be payable, the liquidation amount and the dates on which distributions will be payable.

        Each trust will use the proceeds from the issuance and sale of the trust preferred securities to purchase debt securities. The revenue of a trust available for distribution to holders of the trust preferred securities issued by that trust will be limited to payments under those debt securities. If we do not make payments on the debt securities, a trust will not have funds available to pay distributions or other amounts payable on the trust preferred securities issued by that trust. The payment of distributions and other amounts payable on the trust preferred securities issued by a trust, if and to the extent the trust has funds legally available for and cash sufficient to make such payments, is guaranteed by us on a limited basis.

Option to Extend Interest Payment Period

        Unless the applicable prospectus supplement states otherwise, we have the right to defer the payment of interest on the debt securities at any time or from time to time for a period, which we refer to in this prospectus as an "extension period," not exceeding 20 consecutive quarterly periods with respect to each extension period. During each extension period we shall have the right to make partial payments of interest on any interest payment date. At the end of each extension period we shall pay all interest then accrued and unpaid. No extension period may extend beyond the stated maturity of the debt securities or end on a date other than an interest payment date. As a consequence of any such deferral, distributions on the trust preferred securities by a trust will be deferred during any such extension period. Distributions to which holders of the trust preferred securities are entitled will accumulate additional distributions at the rate stated in the applicable prospectus supplement. During an extension period, interest will continue to accrue and holders of debt securities, or holders of trust preferred securities while outstanding, will be required to accrue original issue discount income for United States federal income tax purposes.

        Prior to the termination of any extension period, we may further defer the payment of interest, provided that, unless the applicable prospectus supplement states otherwise, no extension period may exceed 20 consecutive quarterly periods or extend beyond the stated maturity of the debt securities. Upon the termination of any extension period and the payment of all amounts then due, we may elect to begin a new extension period subject to the above conditions. No interest shall be due and payable during an extension period, except at its end. We must give the trustee notice of our election of an extension period at least one business day prior to the earlier of the date the distributions on the trust preferred securities would have been payable but for the election to begin such extension period and the date the property trustee is required to give notice to holders of the trust preferred securities of the record date or the date such distributions are payable, but in any event not less than one business day prior to such record date. The trustee will give notice of our election to begin a new extension period to the holders of the trust preferred securities.

Registration, Transfer and Exchange

        Unless otherwise indicated in the applicable prospectus supplement, each series of trust preferred securities will be issued initially in the form of one or more global securities, in registered form, without coupons, as described under "Book-Entry System." The global trust preferred securities will be registered in the name of a nominee of The Depository Trust Company, as depository, and deposited with, or on behalf of, the depository. Except in the circumstances described under "Book-Entry System," owners of beneficial interests in a global trust preferred security will not be entitled to have

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trust preferred securities registered in their names, will not receive or be entitled to receive physical delivery of any trust preferred securities and will not be considered the registered holders thereof under the related trust agreement.

        Trust preferred securities of any series will be exchangeable for other trust preferred securities of the same series of any authorized denominations of a like aggregate liquidation amount and tenor. Subject to the terms of the trust agreement and the limitations applicable to global securities, trust preferred securities may be presented for exchange or registration of transfer—duly endorsed or accompanied by a duly executed instrument of transfer—at the office of the property trustee, without service charges but upon payment of any taxes and other governmental charges as described in the trust agreement. Such transfer or exchange will be effected upon the property trustee being satisfied with the documents of title and identity of the person making the request.

        The property trustee will not be required to issue, register the transfer of, or exchange any trust preferred securities during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any trust preferred securities called for redemption and ending at the close of business on the day of mailing or register the transfer of, or exchange, any trust preferred securities selected for redemption except, in the case of any trust preferred security to be redeemed in part, the portion thereof not to be so redeemed.

Payment and Paying Agents

        Distributions and other payments on trust preferred securities issued in the form of global securities will be paid in the manner described under "Book-Entry System."

        Unless otherwise indicated in the applicable prospectus supplement, distributions and other payments with respect to trust preferred securities that are in the form of certificated securities will be made by check mailed to the person entitled thereto at such person's address as such address appears on the securities register for the trust securities maintained by the property trustee. The paying agent initially will be the property trustee and any co-paying agent chosen by the property trustee and acceptable to the administrators. If the property trustee is no longer the paying agent, the property trustee will appoint a successor, which must be a bank or trust company reasonably acceptable to the administrators, to act as paying agent. Such paying agent will be permitted to resign as paying agent upon 30 days' written notice to the property trustee and the administrators at which time the paying agent will return all unclaimed funds and all other funds in its possession to the property trustee.

Redemption

        Upon the repayment or redemption, in whole or in part, of the debt securities held by a trust, the proceeds shall be applied by the property trustee to redeem a Like Amount, as defined below, of the trust securities issued by that trust, upon not less than 30 nor more than 60 days' notice, unless otherwise indicated in a prospectus supplement, at a redemption price equal to the aggregate liquidation amount of the trust preferred securities plus accumulated but unpaid distributions to but excluding the redemption date and the related amount of the premium, if any, paid by us upon the concurrent redemption of the debt securities. If less than all the debt securities held by a trust are to be repaid or redeemed on a redemption date, then the proceeds from the repayment or redemption shall be allocated to the redemption proportionately of the trust preferred securities and the trust common securities issued by that trust based on the relative liquidation amounts of the classes. The amount of premium, if any, paid by us upon the redemption of all or any part of the debt securities held by a trust to be repaid or redeemed on a redemption date shall be allocated to the redemption proportionately of the trust preferred securities and the trust common securities issued by that trust.

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        Unless the applicable prospectus supplement states otherwise, we will have the right to redeem the debt securities held by a trust:

        "Like Amount" means:

        "Tax Event" means the receipt by a trust of an opinion of counsel to us experienced in relevant matters to the effect that, as a result of any amendment to, or change—including any announced prospective change—in, the laws or any regulations thereunder of the United States or any political subdivision or taxing authority of or in the United States, or as a result of any official or administrative pronouncement or action or judicial decision interpreting or applying these laws or regulations, which amendment or change is effective or which pronouncement or decision is announced on or after the date of issuance by a trust of trust preferred securities, including, without limitation, any of the foregoing arising with respect to, or resulting from, any proposal, proceeding or other action commencing on or before the date of issuance, there is more than an insubstantial risk that:

        "Investment Company Event" means the receipt by a trust of an opinion of counsel to us experienced in these matters to the effect that, as a result of the occurrence of a change in law or regulation or a written change—including any announced prospective change—in interpretation or application of law or regulation by any legislative body, court, governmental agency or regulatory authority, there is more than an insubstantial risk that the trust is or will be considered an "investment company" that is required to be registered under the Investment Company Act, which change or prospective change becomes effective or would become effective, as the case may be, on or after the date of the issuance by that trust of trust preferred securities.

        If and for so long as a trust is the holder of all the debt securities issued by us to that trust, we will pay, with respect to the debt securities, such additional amounts as may be necessary in order that the amount of distributions then due and payable by a trust on the outstanding trust preferred

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securities and trust common securities of a trust will not be reduced as a result of any additional taxes, duties and other governmental charges to which that trust has become subject, including as a result of a Tax Event.

Redemption Procedures

        Trust preferred securities of a trust redeemed on each redemption date shall be redeemed at the redemption price with the applicable proceeds from the contemporaneous redemption of the debt securities held by that trust. Redemptions of trust preferred securities shall be made and the redemption price shall be payable on each redemption date only to the extent that a trust has funds on hand available for the payment of the redemption price. See also "—Subordination of Trust Common Securities."

        If a trust gives a notice of redemption in respect of any trust preferred securities, then, by 12:00 noon, New York City time, on the redemption date, to the extent funds are available, in the case of trust preferred securities held in book-entry form, the property trustee will deposit irrevocably with the depository funds sufficient to pay the applicable redemption price and will give the depository irrevocable instructions and authority to pay the redemption price to the holders of the trust preferred securities. With respect to trust preferred securities not held in book-entry form, the property trustee, to the extent funds are available, will irrevocably deposit with the paying agent for the trust preferred securities funds sufficient to pay the applicable redemption price and will give the paying agent irrevocable instructions and authority to pay the redemption price to the holders upon surrender of their certificates evidencing the trust preferred securities. Notwithstanding the foregoing, distributions payable on or prior to the redemption date for any trust preferred securities called for redemption shall be payable to the holders of the trust preferred securities on the relevant record dates for the related distribution dates. If notice of redemption shall have been given and funds deposited as required, then upon the date of the deposit all rights of the holders of the trust preferred securities so called for redemption will cease, except the right of the holders of the trust preferred securities to receive the redemption price, and any distribution payable in respect of the trust preferred securities, but without interest on the redemption price, and the trust preferred securities will cease to be outstanding. In the event that payment of the redemption price in respect of trust preferred securities called for redemption is improperly withheld or refused and not paid either by a trust or by us pursuant to the guarantee as described under "Description of Guarantees," distributions on the trust preferred securities will continue to accumulate at the then applicable rate, from the redemption date originally established by a trust for the trust preferred securities it issues to the date the redemption price is actually paid, in which case the actual payment date will be the date fixed for redemption for purposes of calculating the redemption price.

        If less than all the trust preferred securities and trust common securities are to be redeemed on a redemption date, then the aggregate liquidation amount of the trust preferred securities and trust common securities to be redeemed shall be allocated proportionately to the trust preferred securities and the trust common securities based upon the relative liquidation amounts of the classes. The particular trust preferred securities to be redeemed shall be selected on a proportionate basis not more than 60 days prior to the redemption date by the property trustee from the outstanding trust preferred securities not previously called for redemption, or if the trust preferred securities are then held in the form of a global trust preferred security, in accordance with the depository's customary procedures. The property trustee shall promptly notify the securities registrar for the trust securities in writing of the trust preferred securities selected for redemption and, in the case of any trust preferred securities selected for partial redemption, the liquidation amount to be redeemed. For all purposes of the trust agreements, unless the context otherwise requires, all provisions relating to the redemption of trust preferred securities shall relate, in the case of any trust preferred securities redeemed or to be

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redeemed only in part, to the portion of the aggregate liquidation amount of trust preferred securities which has been or is to be redeemed.

        Notice of any redemption will be mailed at least 30 days but not more than 60 days before the redemption date to each registered holder of trust preferred securities to be redeemed at its address appearing on the securities register for the trust securities. Unless we default in payment of the redemption price on the related debt securities, on and after the redemption date interest will cease to accrue on the debt securities or portions of them called for redemption.

Subordination of Trust Common Securities

        If on any distribution date or redemption date a payment event of default with respect to the underlying debt securities has occurred and is continuing, no payment on or in respect of the related trust common securities shall be made unless all amounts due in respect of the related trust preferred securities (including the liquidation amount or redemption price, if applicable) shall have been paid or payment provided for. All funds immediately available to the respective property trustee shall first be applied to the payment in full in cash of all distributions on, or redemption price of, the trust preferred securities then due and payable.

        In the case of any event of default, as defined below, resulting from an event of default with respect to the underlying debt securities, the holders of trust common securities will be deemed to have waived any right to act with respect to any event of default under the related trust agreement until the effects of all events of default with respect to the related trust preferred securities have been cured, waived or otherwise eliminated. See "—Events of Default" and "Description of Debt Securities—Events of Default." Until all events of default under the related trust agreement with respect to the trust preferred securities have been so cured, waived or otherwise eliminated, the property trustee will act solely on behalf of the holders of the trust preferred securities and not on behalf of the holders of the trust common securities, and only the holders of the trust preferred securities will have the right to direct the property trustee to act on their behalf.

Liquidation Distribution Upon Dissolution

        In the event of any liquidation of a trust, the applicable prospectus supplement will state the amount payable on the trust preferred securities issued by that trust as a dollar amount per trust preferred security plus accumulated and unpaid distributions to the date of payment, subject to certain exceptions, which may be in the form of a distribution of the amount in debt securities held by that trust.

        The holders of all the outstanding trust common securities of a trust have the right at any time to dissolve the trust and, after satisfaction of liabilities to creditors of the trust as provided by applicable law, cause the debt securities held by that trust to be distributed in liquidation of the trust to the holders of the trust preferred securities and trust common securities issued by the trust.

        Pursuant to the related trust agreement, unless the applicable prospectus supplement states otherwise, a trust will automatically dissolve upon expiration of its term or, if earlier, will dissolve on the first to occur of:

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        If dissolution of a trust occurs as described in the first, second or fourth bullet point above, the trust will be liquidated by the property trustee as expeditiously as the property trustee determines to be possible by distributing, after satisfaction of liabilities to creditors of the trust as provided by applicable law, to the holders of the trust securities issued by the trust a Like Amount of the related debt securities. If such distribution is not practical, or, if a dissolution of a trust occurs as described in the third bullet point above, the holders will be entitled to receive out of the assets of the trust available for distribution to holders, after satisfaction of liabilities to creditors of the trust as provided by applicable law, an amount equal to, in the case of holders of the trust preferred securities, the aggregate of the liquidation amount plus accumulated and unpaid distributions to the date of payment. In this prospectus we refer to this amount as the "liquidation distribution." If the liquidation distribution can be paid only in part because the trust has insufficient assets available to pay in full the aggregate liquidation distribution, then the amounts payable directly by the trust on its trust preferred securities shall be paid on a proportionate basis. The holders of the trust common securities issued by the trust will be entitled to receive distributions upon any liquidation proportionately with the holders of the trust preferred securities, except that if a payment event of default has occurred and is continuing on the related debt securities, the trust preferred securities shall have a priority over the trust common securities. See "—Subordination of Trust Common Securities."

        After the liquidation date is fixed for any distribution of debt securities we have issued to a trust,


        If we do not redeem the debt securities we have issued to a trust prior to the stated maturity and the trust is not liquidated and the debt securities are not distributed to holders of the trust preferred securities issued by that trust, the trust preferred securities will remain outstanding until the repayment of the debt securities and the distribution of the liquidation distribution to the holders of the trust preferred securities.

        There can be no assurance as to the market prices for trust preferred securities or the related debt securities that may be distributed in exchange for trust preferred securities if a dissolution and liquidation of a trust were to occur. Accordingly, the trust preferred securities that an investor may purchase, or the related debt securities that the investor may receive on dissolution and liquidation of a trust, may trade at a discount to the price that the investor paid to purchase the trust preferred securities offered hereby.

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Certain Covenants

        In connection with the issuance of trust preferred securities by a trust, we will agree:

        Unless the applicable prospectus supplement states otherwise, we will also agree that we will not (1) declare or pay any dividends or distributions on, or redeem, purchase, acquire or make a liquidation payment with respect to, any of our capital stock, (2) make any payment of principal of or interest or premium, if any, on or repay, repurchase or redeem any debt securities of ours that rank equally with, or junior to, the debt securities (or, with respect to senior deferrable debt securities, make any payment of interest on senior deferrable debt securities with similar deferral provisions or make any payment of principal of or interest or premium, if any, on or repay, repurchase or redeem any debt securities that rank junior to such senior deferrable debt securities), or (3) make any guarantee payments with respect to any guarantee issued by us if such guarantee ranks equally with, or junior to, the debt securities (or, with respect to senior deferrable debt securities, make any guarantee payments with respect to any guarantee issued by us if such guarantee ranks junior to such senior deferrable debt securities), other than, in each case:

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        if at such time

        We will also agree that, if and for so long as a trust is the holder of all debt securities issued by us in connection with the issuance of trust preferred securities by that trust and that trust is required to pay any additional taxes, duties or other governmental charges, including in connection with a Tax Event, we will pay as additional sums on the debt securities the amounts that may be required so that the distributions payable by that trust will not be reduced as a result of any additional taxes, duties or other governmental charges.

Events of Default

        Any one of the following events constitutes an event of default with respect to the trust preferred securities issued by a trust under the related trust agreement:


        Within five business days after the occurrence of certain events of default actually known to the respective property trustee, the property trustee will transmit notice of the event of default to the respective holders of trust securities and the respective administrators, unless the event of default has been cured or waived. Within five business days after the receipt of notice that we intend to exercise our right under the applicable indenture to defer the payment of interest on the related debt securities, the property trustee must notify the holders and the administrators that we intend to defer these interest payments, unless we have revoked our determination to do so.

        The applicable trust agreement includes provisions as to the duties of the property trustee in case an event of default occurs and is continuing. Consistent with these provisions, the property trustee will be under no obligation to exercise any of its rights or powers at the request or direction of any of the

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holders unless those holders have offered to the property trustee reasonable indemnity. Subject to these provisions for indemnification, the holders of a majority in liquidation amount of the related outstanding trust preferred securities may direct the time, method and place of conducting any proceeding for any remedy available to the property trustee, or exercising any trust or power conferred on the property trustee, with respect to the related trust preferred securities.

        The holders of at least a majority in aggregate liquidation amount of the outstanding trust preferred securities issued by a trust may waive any past default under the applicable trust agreement except:

        If an event of default under the applicable indenture has occurred and is continuing as a result of any failure by us to pay any amounts when due in respect of the related debt securities issued by us to a trust, the related trust preferred securities will have a preference over the related trust common securities with respect to payments of any amounts in respect of the trust preferred securities as described above. See "—Subordination of Trust Common Securities," "—Liquidation Distribution Upon Dissolution" and "Description of Debt Securities—Events of Default."

        We must furnish annually to each property trustee a statement by an appropriate officer as to that officer's knowledge of our compliance with all conditions and covenants under the respective trust agreement. Also, the administrators for each trust must file, on behalf of the respective trust, a statement as to our compliance with all conditions and covenants under the respective trust agreement.

Voting Rights; Amendment of Trust Agreement

        Except as provided below and under "—Resignation, Removal of Property Trustee and Delaware Trustee; Appointment of Successors" and "Description of Guarantees—Amendments and Assignment" and as otherwise required by law and the applicable trust agreement, the holders of the trust preferred securities issued by a trust will have no voting rights.

        The trust agreement applicable to a trust may be amended from time to time by the holders of a majority in liquidation amount of its trust common securities and the respective property trustee, without the consent of the holders of the trust preferred securities issued by the trust:

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        The trust agreement may be amended by the holders of a majority in aggregate liquidation amount of the trust common securities and the property trustee with the consent of holders representing not less than a majority in aggregate liquidation amount of the outstanding trust preferred securities and receipt by the property trustee and the Delaware trustee of an opinion of counsel to the effect that the amendment or the exercise of any power granted to the trustees in accordance with the amendment will not affect the trust's not being taxable other than as a grantor trust for United States federal income tax purposes or the trust's exemption from status as an "investment company" under the Investment Company Act.

        Without the consent of each holder of trust preferred securities affected by the amendment or related exercise of power, the trust agreement applicable to a trust may not be amended to change the amount or timing of any distribution on the trust securities or otherwise adversely affect the amount of any distribution required to be made in respect of the trust securities as of a specified date or restrict the right of a holder of trust securities to institute suit for the enforcement of any payment due.

        So long as any debt securities are held by a trust, the respective property trustee will not:

without, in each case, obtaining the prior approval of the holders of at least a majority in aggregate liquidation amount of the trust preferred securities, except that, if a consent under the applicable indenture would require the consent of each holder of debt securities affected by the consent, no consent will be given by the property trustee without the prior written consent of each holder of the trust preferred securities.

        A property trustee may not revoke any action previously authorized or approved by a vote of the holders of the trust preferred securities issued by its respective trust except by subsequent vote of the holders of the trust preferred securities. The property trustee will notify each holder of trust preferred securities of any notice of default with respect to the debt securities. In addition, before taking any of the foregoing actions, the property trustee will obtain an opinion of counsel experienced in relevant matters to the effect that the trust will not be taxable other than as a grantor trust for United States federal income tax purposes on account of the action.

        Any required approval of holders of trust preferred securities issued by a trust may be given at a meeting of holders of those trust preferred securities convened for the purpose or pursuant to written consent. The property trustee will cause a notice of any meeting at which holders of trust preferred securities are entitled to vote, or of any matter upon which action by written consent of the holders is to be taken, to be given to each registered holder of trust preferred securities in the manner set forth in the applicable trust agreement.

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        No vote or consent of the holders of trust preferred securities issued by a trust will be required to redeem and cancel those trust preferred securities in accordance with the applicable trust agreement. See above under "—Redemption."

        Notwithstanding that holders of trust preferred securities issued by a trust are entitled to vote or consent under any of the circumstances described above, any of those trust preferred securities that are owned by us, the respective property trustee or Delaware trustee, or any affiliate of us or either trustee, will, for purposes of the vote or consent, be treated as if they were not outstanding.

Enforcement of Certain Rights by Holders of Trust Preferred Securities

        If an event of default has occurred and is continuing under the applicable indenture, and the trustee for the related debt securities and the holders of those debt securities have failed to declare the principal due and payable, the holders of at least 33% in aggregate liquidation amount of the related outstanding trust preferred securities shall have this right.

        If an event of default has occurred and is continuing under a trust agreement and the event is attributable to our failure to pay any amounts payable in respect of debt securities on the date the amounts are otherwise payable, a registered holder of trust preferred securities may institute a direct action against us for enforcement of payment to the holder of an amount equal to the amount payable in respect of debt securities having a principal amount equal to the aggregate liquidation amount of the trust preferred securities held by the holder, which we refer to in this discussion as a "Direct Action." We will have the right under the applicable indenture to set-off any payment made to the holders of trust preferred securities by us in connection with a Direct Action.

        We may not amend the applicable indenture to remove the foregoing right to bring a Direct Action without the prior written consent of the holders of all the trust preferred securities. Furthermore, so long as any of the trust preferred securities are outstanding

without the prior consent of the holders of at least a majority of the aggregate liquidation amount of the outstanding trust preferred securities unless and until the principal of, accrued and unpaid interest on and premium, if any, on the related debt securities have been paid in full and certain other conditions are satisfied.

        With certain exceptions, the holders of the trust preferred securities would not be able to exercise directly any remedies available to the holders of the debt securities except under the circumstances described in this section.

Resignation, Removal of Property Trustee and Delaware Trustee; Appointment of Successors

        The property trustee or the Delaware trustee of a trust may resign at any time by giving written notice to us or may be removed at any time by an action of the holders of a majority in liquidation amount of that trust's outstanding trust preferred securities delivered to the trustee to be removed and to us. No resignation or removal of either of the trustees and no appointment of a successor trustee will become effective until a successor trustee accepts appointment in accordance with the requirements of the trust agreement. So long as no event of default or event that would become an event of default has occurred and is continuing, and except with respect to a trustee appointed by an action of the holders, if we have delivered to either the property trustee or the Delaware trustee a resolution of our

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board of directors appointing a successor trustee and the successor trustee has accepted the appointment in accordance with the terms of the trust agreement, the property trustee or the Delaware trustee, as the case may be, will be deemed to have resigned and the successor trustee will be deemed to have been appointed as trustee in accordance with the trust agreement.

Mergers, Consolidations, Amalgamations or Replacements of a Trust

        A trust may not merge with or into, consolidate, amalgamate, or be replaced by, or convey, transfer or lease its properties and assets substantially as an entirety to any entity, except as described below or as otherwise set forth in the applicable trust agreement. A trust may, at the request of the holders of its trust common securities and with the consent of the holders of at least a majority in aggregate liquidation amount of its outstanding trust preferred securities, merge with or into, consolidate, amalgamate, or be replaced by or convey, transfer or lease its properties and assets substantially as an entirety to a trust organized as such under the laws of any state, so long as:

        Notwithstanding the foregoing, a trust may not, except with the consent of holders of 100% in aggregate liquidation amount of the trust preferred securities, consolidate, amalgamate, merge with or into, or be replaced by or convey, transfer or lease its properties and assets substantially as an entirety to, any other entity or permit any other entity to consolidate, amalgamate, merge with or into, or replace it if the consolidation, amalgamation, merger, replacement, conveyance, transfer or lease would

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cause the trust or the successor entity to be taxable other than as a grantor trust for United States federal income tax purposes.

Expenses and Taxes

        In each of the trust agreements, we have agreed to pay:

Information Concerning the Property Trustees

        Each property trustee, other than during the occurrence and continuance of an event of default, undertakes to perform only the duties as are specifically set forth in the applicable trust agreement and, after an event of default, must exercise the same degree of care and skill as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, each property trustee is under no obligation to exercise any of the powers vested in it by the trust agreements at the request of any holder of trust preferred securities issued by the respective trust unless it is offered reasonable indemnity against the costs, expenses and liabilities that might be incurred by exercising these powers.

Miscellaneous

        The administrators and the property trustee relating to each trust are authorized and directed to conduct the affairs of and to operate the trust in such a way that the trust will not be deemed to be an "investment company" required to be registered under the Investment Company Act or taxable other than as a grantor trust for United States federal income tax purposes and so that the debt securities held by that trust will be treated as indebtedness of ours for United States federal income tax purposes. In this regard, each property trustee and the holders of trust common securities issued by the respective trust are authorized to take any action, not inconsistent with applicable law, the certificate of trust of the trust or the applicable trust agreement, that the property trustee and the holders of trust common securities determine in their discretion to be necessary or desirable for these purposes, as long as this action does not materially adversely affect the interests of the holders of the trust preferred securities.

        Holders of the trust preferred securities have no preemptive or similar rights.

        A trust may not borrow money or issue debt or mortgage or pledge any of its assets.

Governing Law

        The trust agreement and the trust preferred securities will be governed by Delaware law.

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DESCRIPTION OF GUARANTEES

        Each guarantee will be executed and delivered by us concurrently with the issuance of trust preferred securities by a trust for the benefit of the holders from time to time of the trust preferred securities. We will appoint a guarantee trustee under each guarantee. Each guarantee trustee will hold the respective guarantee for the benefit of the holders of the trust preferred securities issued by the related trust. Each guarantee will be qualified as an indenture under the Trust Indenture Act of 1939. We have summarized below certain provisions of the guarantees. This summary does not purport to be complete and is subject to, and qualified in its entirety by reference to, all the provisions of the guarantee, including the definitions in the guarantee of certain terms. The form of guarantee agreement is filed as an exhibit to the registration statement of which this prospectus is a part.

General

        We will fully and unconditionally agree, to the extent described herein, to pay the guarantee payments, as defined below, to the holders of the trust preferred securities issued by each trust, as and when due, regardless of any defense, right of set-off or counterclaim that a trust may have or assert other than the defense of payment. The following payments with respect to the trust preferred securities, to the extent not paid or made by or on behalf of the respective trust, which payments we refer to in this discussion as the "guarantee payments," will be subject to the respective guarantee:

Our obligation to make a guarantee payment may be satisfied by direct payment of the required amounts by us to the holders of the trust preferred securities or by causing the trust to pay these amounts to the holders.

        Each guarantee will be an irrevocable guarantee of the obligations of the respective trust under its trust preferred securities, but will apply only to the extent that the trust has funds sufficient to make these payments, and is not a guarantee of collection.

        If we do not make payments on the debt securities held by a trust, the trust will not be able to pay any amounts payable in respect of its trust preferred securities and will not have funds legally available for these payments. The applicable prospectus supplement will describe the ranking of the guarantee. See "—Status of the Guarantees." The guarantees do not limit our incurrence or issuance of other secured or unsecured debt, including Senior Indebtedness, whether under the applicable indenture, any other indenture that we may enter into in the future or otherwise.

        We have, through the guarantees, the trust agreements, the applicable debt securities and the related indenture, taken together, fully, irrevocably and unconditionally guaranteed all of each trust's

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obligations under its trust preferred securities. No single document standing alone or operating in conjunction with fewer than all the other documents constitutes the guarantee. It is only the combined operation of these documents that has the effect of providing a full, irrevocable and unconditional guarantee of each trust's obligations in respect of its trust preferred securities. See "Relationship Among Trust Preferred Securities, Debt Securities and Guarantees."

Status of the Guarantees

        Each guarantee will constitute an unsecured obligation of ours. The applicable prospectus supplement will describe the ranking of each guarantee.

        Each guarantee will constitute a guarantee of payment and not of collection; specifically, the guaranteed party may institute a legal proceeding directly against the guarantor to enforce its rights under the guarantee without first instituting a legal proceeding against any other person or entity. Each guarantee will be held by the respective guarantee trustee for the benefit of the holders of the related trust preferred securities. A guarantee will not be discharged except by payment of the applicable guarantee payments in full to the extent not paid or distributed by the respective trust.

Amendments and Assignment

        Except with respect to any changes that do not materially adversely affect the rights of holders of the related trust preferred securities, in which case no vote will be required, a guarantee may not be amended without the prior approval of the holders of not less than a majority of the aggregate liquidation amount of the related trust preferred securities. The manner of obtaining this type of approval will be as set forth under "Description of Trust Preferred Securities—Voting Rights; Amendment of Trust Agreement." All guarantees and agreements contained in each guarantee shall bind the successors, assigns, receivers, trustees and representatives of ours and shall inure to the benefit of the holders of the related trust preferred securities then outstanding.

Events of Default

        An event of default under a guarantee will occur upon our failure to perform any of our payment or other obligations under the guarantee, or to perform any other obligation if such default remains unremedied for 30 days.

        The holders of not less than a majority in aggregate liquidation amount of the related trust preferred securities have the right to direct the time, method and place of conducting any proceeding for any remedy available to the guarantee trustee in respect of the guarantee or to direct the exercise of any trust or power conferred upon the guarantee trustee under the guarantee. Any registered holder of trust preferred securities may institute a legal proceeding directly against us to enforce its rights under the related guarantee without first instituting a legal proceeding against the related trust, the guarantee trustee or any other person or entity.

        We, as guarantor, are required to file annually with each guarantee trustee a certificate as to whether or not we are in compliance with all the conditions and covenants applicable to us under each guarantee.

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Consolidation, Merger, Sale of Assets and Other Transactions

        Each guarantee provides that:

        unless

Information Concerning the Guarantee Trustee

        The guarantee trustee, other than during the occurrence and continuance of a default by us in performance of the guarantee, undertakes to perform only such duties as are specifically set forth in the guarantee agreement. After a default with respect to the guarantee, the guarantee trustee must exercise the same degree of care and skill as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the guarantee trustee is under no obligation to exercise any of the powers vested in it by the guarantee agreement at the request of any holder of the trust preferred securities unless it is offered reasonable indemnity against the costs, expenses and liabilities that it might thereby incur.

Termination of the Guarantees

        Each guarantee will terminate and be of no further force and effect upon full payment of the redemption price of the related trust preferred securities, upon full payment of the amounts payable with respect to the trust preferred securities upon liquidation of the respective trust and upon distribution of the related debt securities to the holders of the trust preferred securities. Each guarantee will continue to be effective or will be reinstated, as the case may be, if at any time any holder of the related trust preferred securities must restore payment of any sums paid under the trust preferred securities or the guarantee.

Governing Law

        Each guarantee will be governed by New York law.

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RELATIONSHIP AMONG TRUST PREFERRED SECURITIES,
DEBT SECURITIES AND GUARANTEES

Full and Unconditional Guarantee

        Payments of distributions and other amounts due on the trust preferred securities issued by a trust, to the extent the trust has funds available for the payment, are irrevocably guaranteed by us as and to the extent set forth under "Description of Guarantees." Taken together, our obligations under the related debt securities, the applicable indenture, the related trust agreement and the related guarantee provide, in the aggregate, a full, irrevocable and unconditional guarantee of payments of distributions and other amounts due on the trust preferred securities issued by a trust. No single document standing alone or operating in conjunction with fewer than all the other documents constitutes the guarantee. It is only the combined operation of these documents that has the effect of providing a full, irrevocable and unconditional guarantee of each trust's obligations in respect of the related trust preferred securities. If and to the extent that we do not make payments on the debt securities issued to a trust, the trust will not have sufficient funds to pay distributions or other amounts due on its trust preferred securities. A guarantee does not cover payment of amounts payable with respect to the trust preferred securities issued by a trust when the trust does not have sufficient funds to pay these amounts. In this event, the remedy of a holder of the trust preferred securities is to institute a legal proceeding directly against us for enforcement of payment of our obligations under debt securities having a principal amount equal to the liquidation amount of the trust preferred securities held by the holder.

Sufficiency of Payments

        As long as payments are made when due on the debt securities issued to a trust, these payments will be sufficient to cover distributions and other payments distributable on the trust preferred securities issued by that trust, primarily because:

        Notwithstanding anything to the contrary in the applicable indenture, we have the right to set-off any payment we are otherwise required to make under that indenture against and to the extent we have previously made, or are concurrently on the date of the payment making, a payment under a guarantee.

Enforcement Rights of Holders of Trust Preferred Securities

        Under the circumstances set forth under "Description of Trust Preferred Securities—Enforcement of Certain Rights by Holders of Trust Preferred Securities," holders of trust preferred securities may bring a Direct Action against us.

        A holder of any trust preferred security may institute a legal proceeding directly against us to enforce its rights under the related guarantee without first instituting a legal proceeding against the related guarantee trustee, the related trust or any other person or entity. See "Description of Guarantees."

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Limited Purpose of Trust

        The trust preferred securities issued by a trust represent preferred undivided beneficial interests in the assets of the trust, and the trust exists for the sole purpose of issuing its trust preferred securities and trust common securities and investing the proceeds of these trust securities in debt securities. A principal difference between the rights of a holder of a trust preferred security and a holder of a debt security is that a holder of a debt security is entitled to receive from us payments on debt securities held, while a holder of trust preferred securities is entitled to receive distributions or other amounts distributable with respect to the trust preferred securities from a trust, or from us under a guarantee, only if and to the extent the trust has funds available for the payment of the distributions.

Rights Upon Dissolution

        Upon any voluntary or involuntary dissolution of a trust, other than any dissolution involving the distribution of the related debt securities, after satisfaction of liabilities to creditors of the trust as required by applicable law, the holders of the trust preferred securities issued by the trust will be entitled to receive, out of assets held by the trust, the liquidation distribution in cash. See "Description of Trust Preferred Securities—Liquidation Distribution Upon Dissolution." Since we are the guarantor under each of the guarantees and have agreed to pay for all costs, expenses and liabilities of each trust, other than each trust's obligations to the holders of the respective trust securities, the positions of a holder of trust preferred securities and a holder of debt securities relative to other creditors and to our shareholders in the event of our liquidation or bankruptcy are expected to be substantially the same.

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DESCRIPTION OF COMMON STOCK

General

        The following descriptions of our common stock and the relevant provisions of our restated articles of incorporation and by-laws are summaries and are qualified by reference to our restated articles of incorporation and by-laws which have been previously filed with the SEC and are exhibits to this registration statement, of which this prospectus is a part, as well as the applicable Missouri General and Business Corporation Law.

        Under our restated articles of incorporation, we are authorized to issue 400 million shares of common stock, $.01 par value per share, and 100 million shares of preferred stock, $.01 par value per share. At December 31, 2001, 138,045,639 shares of common stock and no shares of preferred stock were outstanding.

Dividend Rights and Limitations

        The holders of our common stock are entitled to receive such dividends as our board of directors may from time to time declare, subject to any rights of the holders of our preferred stock, if any is issued. Our ability to pay dividends depends primarily upon the ability of our subsidiaries to pay dividends or otherwise transfer funds to us. Various financing arrangements, charter provisions and regulatory requirements may impose certain restrictions on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans or advances.

Voting Rights

        Except as otherwise provided by law and subject to the voting rights of holders of our preferred stock, the holders of our common stock have the exclusive right to vote for the election of directors and for all other purposes. Each holder of our common stock is entitled to one vote per share on all matters submitted to a vote at a meeting of shareholders, including the election of directors, which means that the holders of more than 50% of the shares voting for the election of directors can elect 100% of the directors and the holders of the remaining shares voting for the election of directors will not be able to elect any directors. The common stock shall vote together as a single class. The holders of our common stock are not entitled to cumulate votes for the election of directors. At annual and special meetings of stockholders, a majority of the outstanding shares of common stock constitutes a quorum.

Liquidation Rights

        In the event of any liquidation, dissolution or winding up of our affairs, voluntarily or involuntarily, the holders of our common stock will be entitled to receive the remainder, if any, of our assets after the payment of all our debts and liabilities and after the payment in full of any preferential amounts to which holders of any preferred stock may be entitled.

Miscellaneous

        The outstanding shares of common stock are, and the shares of common stock sold hereunder will be, upon payment for them, fully paid and nonassessable. The holders of our common stock are not entitled to any preemptive or preferential rights to subscribe for or purchase any part of any new or additional issue of stock or securities convertible into stock. Our common stock does not contain any redemption provisions or conversion rights.

Transfer Agent and Registrar

        Ameren Services Company acts as transfer agent and registrar for the common stock.

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Shareholder Rights Plan

        On October 9, 1998, our board of directors adopted a shareholder rights plan and declared a dividend of one preferred share purchase right for each outstanding share of our common stock. The plan is designed to assure shareholders of fair and equal treatment in the event of a proposed takeover. Each right entitles the registered holder to purchase from us one one-hundredth of a share of Series A junior participating preferred stock, par value $.01 per share, at an exercise price of $180 per one one-hundredth of a share of such preferred stock, subject to adjustment. The rights will become exercisable only if a person or group acquires 15% or more of our common stock or announces a tender offer, the consummation of which would result in ownership by a person or group of 15% or more of our common stock. If a person or group acquires 15% or more of our outstanding common stock, each right will entitle its holder (other than such person or members of such group) to purchase, at the right's then-current exercise price, a number of shares of our common stock having a market value of twice such price. In addition, if we are acquired in a merger or other business combination transaction after a person or group has acquired 15% or more of our outstanding common stock, each right will entitle its holder to purchase, at the right's then-current exercise price, a number of shares of the acquiring company's common stock having a market value of twice such price. The acquiring person or group will not be entitled to exercise these rights.

        The SEC approved the plan under the Public Utility Holding Company Act of 1935 in December 1998. The rights were issued as a dividend payable January 8, 1999, to shareholders of record on that date. The rights will expire on October 9, 2008. One right will accompany each new share of our common stock issued prior to such expiration date. The rights do not have voting or dividend rights, and until they become exercisable, have no dilutive effect on our per-share earnings.

        We have 4 million shares of preferred stock initially reserved for issuance upon exercise of the rights. There is no junior participating preferred stock issued or outstanding as of the date of this prospectus.

        The description and terms of the rights are set forth in an agreement between us and EquiServe Trust Company, N.A. (successor to First Chicago Trust Company of New York), as rights agent. The proceeding summary of the rights and the shareholder rights plan is qualified in its entirety by reference to the rights agreement and the description thereof each contained in our registration statement on Form 8-A dated November 23, 1998, which is incorporated by reference into this prospectus.

Certain Anti-Takeover Matters

        Our restated articles of incorporation and by-laws include a number of provisions that may have the effect of discouraging persons from acquiring large blocks of our stock or delaying or preventing a change in our control. The material provisions that may have such an effect include:

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        In addition, the Missouri General and Business Corporation Law, or the MGBCL, contains certain provisions, including business combination provisions that would be applicable to certain mergers, share exchanges or sales of substantially all assets involving us or a subsidiary and a significant shareholder and which could have the effect of substantially increasing the cost to the acquiror and thus discouraging any such transaction. The MGBCL permits shareholders to adopt an amendment to the articles of incorporation opting out of the business combination provisions, and our restated articles of incorporation opt out of such provisions.

        Under the Illinois Public Utilities Act, approval of the Illinois Commerce Commission is required for any transaction which, regardless of the means by which it is accomplished, results in a change in the ownership of a majority of the voting capital stock of an Illinois public utility or the ownership or control of any entity which owns or controls a majority of the voting capital stock of a public utility. Because we control a majority of the voting stock of AmerenCIPS and AmerenUE, both public utilities subject to Illinois utility regulation, any change in our ownership or control, within the meaning of the Illinois Public Utilities Act, would require Illinois Commerce Commission approval. Certain acquisitions by any person of our outstanding voting shares would also require approval of the SEC under the Public Utility Holding Company Act of 1935.


DESCRIPTION OF STOCK PURCHASE CONTRACTS AND STOCK PURCHASE UNITS

        We may issue stock purchase contracts, including contracts obligating holders to purchase from us, and us to sell to the holders, a specified number of shares of our common stock at a future date or dates, or warrants. The price per share of common stock and the number of shares of common stock may be fixed at the time the stock purchase contracts or warrants are issued or may be determined by reference to a specific formula set forth in the stock purchase contracts. The stock purchase contracts may be issued separately or as part of units, often known as stock purchase units, consisting of a stock purchase contract and beneficial interests in:

securing the holders' obligations to purchase the common stock under the stock purchase contracts. The stock purchase contracts may require us to make periodic payments to the holders of the stock purchase units or vice versa, and these payments may be unsecured or prefunded on some basis. The stock purchase contracts may require holders to secure their obligations under those contracts in a specified manner.

        The applicable prospectus supplement will describe the terms of the stock purchase contracts, stock purchase units or warrants, including, if applicable, collateral or depositary arrangements.


BOOK-ENTRY SYSTEM

        Unless otherwise indicated in the applicable prospectus supplement, each series of debt securities (other than debt securities issued to a trust) and trust preferred securities will initially be issued in the form of one or more global securities, in registered form, without coupons. The global security will be deposited with, or on behalf of, the depository, and registered in the name of the depository or a nominee of the depository. Unless otherwise indicated in the applicable prospectus supplement, the depository for any global securities will be The Depository Trust Company, or DTC.

        So long as the depository, or its nominee, is the registered owner of a global security, such depository or such nominee, as the case may be, will be considered the owner of such global security

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for all purposes under the applicable indenture, including for any notices and voting. Except in limited circumstances, the owners of beneficial interests in a global security will not be entitled to have securities registered in their names, will not receive or be entitled to receive physical delivery of any such securities and will not be considered the registered holder thereof under the applicable indenture. Accordingly, each person holding a beneficial interest in a global security must rely on the procedures of the depository and, if such person is not a direct participant, on procedures of the direct participant through which such person holds its interest, to exercise any of the rights of a registered owner of such security.

        Global securities may be exchanged in whole for certificated securities only if:

In any such case, we have agreed to notify the applicable trustee in writing that, upon surrender by the direct participants and indirect participants of their interest in such global securities, certificated securities representing the applicable securities will be issued to each person that such direct participants and indirect participants and the depository identify as being the beneficial owner of such securities.

        The following is based solely on information furnished by DTC:

        DTC will act as depository for the global securities. The global securities will be issued as fully-registered securities registered in the name of Cede & Co., DTC's partnership nominee. One fully-registered global security certificate will be issued for each issue of the global securities, each in the aggregate principal amount of such issue and will be deposited with DTC.

        DTC is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code, and a "clearing corporation" registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934. DTC holds securities that its direct participants deposit with DTC. DTC also facilitates the settlement among direct participants of securities transactions, such as transfers and pledges, in deposited securities through electronic computerized book-entry changes in direct participants' accounts, thereby eliminating the need for physical movement of securities certificates.

        Direct participants include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. DTC is owned by a number of its direct participants and by the New York Stock Exchange, Inc., the American Stock Exchange, Inc. and the National Association of Securities Dealers, Inc. Access to the DTC system is also available to others such as securities brokers and dealers, banks and trust companies that clear through or maintain a custodial relationship with a direct participant, either directly or indirectly, which are referred to as indirect participants and, together with the direct participants, the participants. The rules applicable to DTC and its participants are on file with the SEC.

        Purchases of global securities under the DTC system must be made by or through direct participants, who will receive a credit for such purchases of global securities on DTC's records. The ownership interest of each actual purchaser of each global security, or beneficial owner, is in turn to be recorded on the direct and indirect participants' records. Beneficial owners will not receive written

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confirmation from DTC of their purchase, but beneficial owners are expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the direct or indirect participant through which the beneficial owner entered into the transaction. Transfers of ownership interests in the global securities are to be accomplished by entries made on the books of participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the global securities, except in the event that use of the book-entry system for the global securities is discontinued.

        To facilitate subsequent transfers, all global securities deposited by participants with DTC are registered in the name of DTC's partnership nominee, Cede & Co. The deposit of global securities with DTC and their registration in the name of Cede & Co. effect no change in beneficial ownership. DTC has no knowledge of the actual beneficial owners of the global securities; DTC's records reflect only the identity of the direct participants to whose accounts such global securities are credited which may or may not be the beneficial owners. The participants will remain responsible for keeping account of their holdings on behalf of their customers.

        Conveyance of notices and other communications by DTC to direct participants, by direct participants to indirect participants, and by direct participants and indirect participants to beneficial owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time.

        If the global securities are redeemable, redemption notices shall be sent to Cede & Co. If less than all of the global securities are being redeemed, DTC's practice is to determine by lot the amount of the interest of each direct participant in such issue to be redeemed.

        Neither DTC nor Cede & Co. will consent or vote with respect to the global securities. Under its usual procedures, DTC mails an omnibus proxy to us as soon as possible after the record date. The omnibus proxy assigns Cede & Co.'s consenting or voting rights to those direct participants whose accounts the global securities are credited on the record date, identified in a listing attached to the omnibus proxy.

        Principal, interest and premium payments, if any, on the global securities will be made to DTC in immediately available funds. DTC's practice is to credit direct participants' accounts on the date on which interest is payable in accordance with the respective holdings shown on DTC's records, unless DTC has reason to believe that it will not receive payment on such date. Payments by participants to beneficial owners will be governed by standing instructions and customary practices, as is the case with securities held for the accounts of customers in bearer form or registered in "street name," and will be the responsibility of such participant and not of DTC, the trustee for such securities, or us, subject to any statutory or regulatory requirements as may be in effect from time to time. Payment of principal, interest and premium, if any, on any of the aforementioned securities represented by global securities to DTC is the responsibility of the appropriate trustee and us. Disbursement of such payments to direct participants shall be the responsibility of DTC, and disbursement of such payments to the beneficial owners shall be the responsibility of the participants.

        The information in this section concerning DTC and DTC's book-entry system has been obtained from sources, including DTC, that we believe to be reliable, but we take no responsibility for the accuracy thereof.

        The underwriters, dealers or agents of any of the securities may be direct participants of DTC.

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         None of the trustees, us or any agent for payment on or registration of transfer or exchange of any global security will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial interests in such global security or for maintaining, supervising or reviewing any records relating to such beneficial interests.


PLAN OF DISTRIBUTION

        We may sell the securities:

        The applicable prospectus supplement will set forth the terms under which the securities are offered, including the name or names of any underwriters, the purchase price of the securities and the proceeds to us from the sale, any underwriting discounts and other items constituting underwriters' compensation, any initial offering price and any discounts, commissions or concessions allowed or reallowed or paid to dealers.

        Any initial offering price and any discounts, concessions or commissions allowed or reallowed or paid to dealers may be changed from time to time.

        If underwriters are used in an offering, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more of those firms. The specific managing underwriter or underwriters, if any, will be named in the prospectus supplement relating to the particular securities together with the members of the underwriting syndicate, if any. Unless otherwise set forth in the applicable prospectus supplement, the obligations of the underwriters to purchase the particular securities will be subject to certain conditions precedent and the underwriters will be obligated to purchase all of the securities being offered if any are purchased.

        We may sell the securities directly or through agents we designate from time to time. The applicable prospectus supplement will set forth the name of any agent involved in the offer or sale of the securities in respect of which such prospectus supplement is delivered and any commissions payable by us to such agent. Unless otherwise indicated in the applicable prospectus supplement, any agent will be acting on a best efforts basis for the period of its appointment.

        Any underwriters utilized may engage in stabilizing transactions and syndicate covering transactions in accordance with Rule 104 of Regulation M under the Securities Exchange Act of 1934. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Syndicate covering transactions involve purchases of the particular offered securities in the open market after the distribution has been completed in order to cover syndicate short positions. These stabilizing transactions and syndicate covering transactions may cause the price of the offered securities to be higher than it would otherwise be in the absence of such transactions.

        Any underwriters, dealers or agents participating in the distribution of the securities may be deemed to be underwriters and any discounts or commissions received by them on the sale or resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. Agents, dealers and underwriters may be entitled, under agreements entered into with us, to indemnification by us against certain liabilities, including liabilities under the Securities Act, and to

42



contribution with respect to payments which the agents, dealers or underwriters may be required to make in respect of these liabilities. Agents, dealers and underwriters may engage in transactions with or perform services for us in the ordinary course of business.

        Unless otherwise specified in a prospectus supplement, except for our common stock, which is listed on the New York Stock Exchange, the securities will not be listed on a national securities exchange. No assurance can be given that any broker-dealer will make a market in any series of the securities, and, in any event, no assurance can be given as to the liquidity of the trading market for any of the securities. The prospectus supplement will state, if known, whether or not any broker-dealer intends to make a market in the securities. If no such determination has been made, the prospectus supplement will so state.


LEGAL MATTERS

        Steven R. Sullivan, Esq., our Vice President, General Counsel and Secretary, will pass upon the validity of the offered securities for us. Pillsbury Winthrop LLP, New York, New York, will pass upon the validity of the offered securities for any underwriters, dealers, purchasers or agents. Pillsbury Winthrop LLP represents us from time to time in connection with various matters.


EXPERTS

        The financial statements incorporated in this prospectus by reference to our Annual Report on Form 10-K for the year ended December 31, 2000 have been so incorporated in reliance upon the report of PricewaterhouseCoopers LLP, independent accountants, given on the authority of said firm as experts in auditing and accounting.

43




PART II. INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

Securities and Exchange Commission registration fee   $ 92,000 *
Printing of registration statement, prospectus, bonds, notes, etc.     46,000  
Fees of trustees     154,000  
Fees of rating agencies     540,000  
Fees of accountants     115,000  
Blue sky fees     5,000  
Miscellaneous expenses     48,000  
   
 
  Total   $ 1,000,000  

*
Actual expenses; all other expenses are estimates.

Item 15. Indemnification of Directors and Officers

        Article IV of the Registrant's By-laws, consistent with the applicable provisions of the Missouri General and Business Corporation Law (the "MGBCL"), provides for indemnification of directors and officers. These provisions provide that any person shall be indemnified for expenses and liabilities imposed upon such person in connection with any threatened, pending or completed action, suit, or proceeding, whether civil, criminal, administrative or investigative, other than an action by or in the right of the Registrant, by reason of the fact that such person is or was a director, officer, employee or agent of the Registrant, or is or was serving at the request of the Registrant as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses, including attorneys' fees, judgments, fines and amounts paid in settlement actually and reasonably incurred by such person in connection with such action, suit or proceeding if such person acted in good faith and in a manner such person reasonably believed to be in or not opposed to the best interests of the Registrant, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful.

        In a proceeding brought by or in the right of the Registrant, indemnification shall be made with respect to any claim as to which an officer or director has been adjudged to have been liable to the Registrant if such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the Registrant. However, no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable for negligence or misconduct in the performance of his duty to the Registrant unless and only to the extent that the court in which the action or suit was brought determines upon application that, despite the adjudication of liability and in view of all the circumstances of the case, the person is fairly and reasonably entitled to indemnity for such expenses which the court shall deem proper.

        The By-laws, consistent with the applicable provisions of the MGBCL, provide that indemnification shall be made by the Registrant only if a determination has been made by a majority vote of a quorum of the disinterested directors or by the shareholders or by independent legal counsel, that the director or officer met the required standard of conduct. The Registrant has purchased insurance on behalf of its officers and directors which insures them against certain liabilities and expenses, including those under the Securities Act of 1933.

        The By-laws, consistent with the applicable provisions of the MGBCL, further provide that, in addition to the indemnities described in the preceding paragraphs, the Registrant will further indemnify its officers and directors to the maximum extent permitted by law, provided that no indemnity may be given for conduct that is adjudged to be knowingly fraudulent, deliberately dishonest, or willful misconduct.

II-1


Item 16. Exhibits

Exhibit No.

  Description
*1.1   Form of Underwriting Agreement relating to the debt securities.

+1.2

 

Form of Underwriting Agreement relating to the trust preferred securities.

*1.3

 

Form of Underwriting Agreement relating to the common stock.

+1.4

 

Form of Underwriting Agreement relating to the stock purchase units.

**4.1

 

Restated Articles of Incorporation of the Company (File No. 33-64165, Annex F).

**4.2

 

Certificate of Amendment to the Restated Articles of Incorporation filed with the Secretary of State of the State of Missouri on December 14, 1998 (1998 Form 10-K, Exhibit 3(i)).

**4.3

 

By-laws of the Company as amended to December 31, 1997 (1997 Form 10-K, Exhibit 3(ii)).

**4.4

 

Agreement, dated as of October 9, 1998, between the Company and EquiServe Trust Company, N.A. (as successor to First Chicago Trust Company of New York), as Rights Agent, which includes the form of Certificate of Designation of the Preferred Shares as Exhibit A, the form of Rights Certificate as Exhibit B and the Summary of Rights as Exhibit C (October 14, 1998 Form 8-K, Exhibit 4).

*4.5

 

Indenture of the Company with The Bank of New York, as trustee, relating to the senior debt securities dated as of December 1, 2001.

*4.6

 

Company order relating to $150,000,000 Floating Rate Notes due December 12, 2003 issued under the senior indenture (including the forms of notes).

*4.7

 

Company order relating to $100,000,000 5.70% Notes due February 1, 2007 issued under the senior indenture (including the forms of notes).

+4.8

 

Form of supplemental indenture or other instrument establishing the issuance of one or more series of senior debt securities (including the form of senior debt security).

+4.9

 

Form of Indenture of the Company relating to subordinated debt securities.

+4.10

 

Form of supplemental indenture or other instrument establishing the issuance of one or more series of subordinated debt securities (including the form of subordinated debt security).

+4.11

 

Form of Guarantee Agreement of the Company.

+4.12

 

Form of Certificate of Trust.

+4.13

 

Form of Trust Agreement.

+4.14

 

Form of Amended and Restated Trust Agreement (including the form of trust preferred security).

+4.15

 

Form of Stock Purchase Contract Agreement.

+4.16

 

Form of Pledge Agreement.

+4.17

 

Form of Warrant Agreement (including the form of warrant).

*5.1

 

Opinion of Steven R. Sullivan, Esq., Vice President, General Counsel and Secretary of the Company, regarding the legality of the securities.

II-2



*5.2

 

Opinion of Pillsbury Winthrop LLP regarding the legality of the securities.

*12

 

Statement re computation of ratios of earnings to fixed charges.

*23.1

 

Consent of Steven R. Sullivan, Esq., Vice President, General Counsel and Secretary of the Company (included in Exhibit 5.1).

*23.2

 

Consent of Pillsbury Winthrop LLP (included in Exhibit 5.2).

*23.3

 

Consent of independent accountants.

*24

 

Powers of attorney.

*25.1

 

Form T-1 statement of eligibility of the trustee for the senior debt securities.

++25.2

 

Form T-1 statement of eligibility of the trustee for the subordinated debt securities.

++25.3

 

Form T-1 statement of eligibility of the trustee for the guarantees for the benefit of the holders of the trust preferred securities.

++25.4

 

Form T-1 statement of eligibility of the trustee for the trust preferred securities.

Note:  Reports of the Company on Forms 8-K, 10-Q and 10-K are on file with the SEC under file number 1-14756.


*
Filed herewith.

**
Incorporated by reference herein as indicated.

+
To be filed by amendment or pursuant to a report to be filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 if applicable.

++
To be filed by amendment or pursuant to Trust Indenture Act Section 305(b)(2) if applicable.

II-3


Item 17. Undertakings .

         The undersigned hereby undertakes:

        (1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

                  (i)    To include any prospectus required by section 10(a)(3) of the Securities Act of 1933;

                (ii)    To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Securities and Exchange Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

                (iii)    To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however , that (i) and (ii) do not apply if the registration statement is on Form S-3 or Form S-8, and the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed by the Company pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement.

        (2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

        (4) That, for purposes of determining any liability under the Securities Act of 1933, each filing of the Company's annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (5) To file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act in accordance with the rules and regulations prescribed by the Commission under Section 305(b)(2) of the Act.

        Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Company pursuant to the provisions described under Item 15 above, or otherwise, the Company has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Company of expenses incurred or paid by a director, officer or controlling person of the Company in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Company will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

II-4



SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of St. Louis, and State of Missouri, on the 30th day of January, 2002.

    AMEREN CORPORATION (REGISTRANT)

 

 

By:

/s/  
CHARLES W. MUELLER       
Charles W. Mueller
Chairman and Chief Executive Officer

        Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the date indicated.

Name
  Title
  Date

 

 

 

 

 
/s/   CHARLES W. MUELLER       
Charles W. Mueller
  Chairman and Chief Executive Officer (Principal Executive Officer)   January 30, 2002

/s/  
GARY L. RAINWATER       
Gary L. Rainwater

 

President and Chief Operating Officer

 

January 30, 2002

/s/  
WARNER L. BAXTER       
Warner L. Baxter

 

Senior Vice President, Finance (Principal Financial Officer)

 

January 30, 2002

/s/  
MARTIN J. LYONS, JR.       
Martin J. Lyons, Jr.

 

Controller (Principal Accounting Officer)

 

January 30, 2002

*

William E. Cornelius

 

Director

 

January 30, 2002

*

Clifford L. Greenwalt

 

Director

 

January 30, 2002

*

Thomas A. Hays

 

Director

 

January 30, 2002

II-5



*

Thomas H. Jacobsen

 

Director

 

January 30, 2002

*

Richard A. Liddy

 

Director

 

January 30, 2002

*

Gordon R. Lohman

 

Director

 

January 30, 2002

*

Richard A. Lumpkin

 

Director

 

January 30, 2002

*

John Peters MacCarthy

 

Director

 

January 30, 2002

*

Hanne M. Merriman

 

Director

 

January 30, 2002

*

Paul L. Miller, Jr.

 

Director

 

January 30, 2002

*

Harvey Saligman

 

Director

 

January 30, 2002

*

Janet McAfee Weakley

 

Director

 

January 30, 2002

*

James W. Wogsland

 

Director

 

January 30, 2002

*By:

 

/s/  
STEVEN R. SULLIVAN     

Steven R. Sullivan
Attorney-in-Fact

 

 

 

 

II-6



EXHIBIT INDEX

Exhibit No.

  Description
*1.1   Form of Underwriting Agreement relating to the debt securities.

+1.2

 

Form of Underwriting Agreement relating to the trust preferred securities.

*1.3

 

Form of Underwriting Agreement relating to the common stock.

+1.4

 

Form of Underwriting Agreement relating to the stock purchase units.

**4.1

 

Restated Articles of Incorporation of the Company (File No. 33-64165, Annex F).

**4.2

 

Certificate of Amendment to the Restated Articles of Incorporation filed with the Secretary of State of the State of Missouri on December 14, 1998 (1998 Form 10-K, Exhibit 3(i)).

**4.3

 

By-laws of the Company as amended to December 31, 1997 (1997 Form 10-K, Exhibit 3(ii)).

**4.4

 

Agreement, dated as of October 9, 1998, between the Company and EquiServe Trust Company, N.A. (as successor to First Chicago Trust Company of New York), as Rights Agent, which includes the form of Certificate of Designation of the Preferred Shares as Exhibit A, the form of Rights Certificate as Exhibit B and the Summary of Rights as Exhibit C (October 14, 1998 Form 8-K, Exhibit 4).

*4.5

 

Indenture of the Company with The Bank of New York, as trustee, relating to the senior debt securities dated as of December 1, 2001.

*4.6

 

Company order relating to $150,000,000 Floating Rate Notes due December 12, 2003 issued under the senior indenture (including the forms of notes).

*4.7

 

Company order relating to $100,000,000 5.70% Notes due February 1, 2007 issued under the senior indenture (including the forms of notes).

+4.8

 

Form of supplemental indenture or other instrument establishing the issuance of one or more series of senior debt securities (including the form of senior debt security).

+4.9

 

Form of Indenture of the Company relating to subordinated debt securities.

+4.10

 

Form of supplemental indenture or other instrument establishing the issuance of one or more series of subordinated debt securities (including the form of subordinated debt security).

+4.11

 

Form of Guarantee Agreement of the Company.

+4.12

 

Form of Certificate of Trust.

+4.13

 

Form of Trust Agreement.

+4.14

 

Form of Amended and Restated Trust Agreement (including the form of trust preferred security).

+4.15

 

Form of Stock Purchase Contract Agreement.

+4.16

 

Form of Pledge Agreement.

+4.17

 

Form of Warrant Agreement (including the form of warrant).

*5.1

 

Opinion of Steven R. Sullivan, Esq., Vice President, General Counsel and Secretary of the Company, regarding the legality of the securities.

*5.2

 

Opinion of Pillsbury Winthrop LLP regarding the legality of the securities.

*12

 

Statement re computation of ratios of earnings to fixed charges.


*23.1

 

Consent of Steven R. Sullivan, Esq., Vice President, General Counsel and Secretary of the Company (included in Exhibit 5.1).

*23.2

 

Consent of Pillsbury Winthrop LLP (included in Exhibit 5.2).

*23.3

 

Consent of independent accountants.

*24

 

Powers of attorney.

*25.1

 

Form T-1 statement of eligibility of the trustee for the senior debt securities.

++25.2

 

Form T-1 statement of eligibility of the trustee for the subordinated debt securities.

++25.3

 

Form T-1 statement of eligibility of the trustee for the guarantees for the benefit of the holders of the trust preferred securities.

++25.4

 

Form T-1 statement of eligibility of the trustee for the trust preferred securities.

Note: Reports of the Company on Forms 8-K, 10-Q and 10-K are on file with the SEC under file number 1-14756.

*
Filed herewith.

**
Incorporated by reference herein as indicated.

+
To be filed by amendment or pursuant to a report to be filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 if applicable.

++
To be filed by amendment or pursuant to Trust Indenture Act Section 305(b)(2) if applicable.



QuickLinks

AMEREN CORPORATION
$1,000,000,000
Senior Debt Securities Subordinated Debt Securities Trust Preferred Securities and Related Guarantees Common Stock Stock Purchase Contracts Stock Purchase Units
ABOUT THIS PROSPECTUS
FORWARD-LOOKING STATEMENTS
AMEREN CORPORATION
WHERE YOU CAN FIND MORE INFORMATION
RATIOS OF EARNINGS TO FIXED CHARGES
USE OF PROCEEDS
DESCRIPTION OF DEBT SECURITIES
DESCRIPTION OF TRUST PREFERRED SECURITIES
DESCRIPTION OF GUARANTEES
RELATIONSHIP AMONG TRUST PREFERRED SECURITIES, DEBT SECURITIES AND GUARANTEES
DESCRIPTION OF COMMON STOCK
DESCRIPTION OF STOCK PURCHASE CONTRACTS AND STOCK PURCHASE UNITS
BOOK-ENTRY SYSTEM
PLAN OF DISTRIBUTION
LEGAL MATTERS
EXPERTS
PART II. INFORMATION NOT REQUIRED IN THE PROSPECTUS
SIGNATURES
EXHIBIT INDEX

EXHIBIT 1.1

AMEREN CORPORATION

$____________

DEBT SECURITIES

UNDERWRITING AGREEMENT

____________, 200_

[Names of Underwriters]
c/o [Name of Lead Underwriter]
[Address]

Ladies and Gentlemen:

Ameren Corporation, a Missouri corporation (the COMPANY), hereby confirms its agreement with you, as underwriters (the "Underwriters"), as follows:

1. PURCHASE AND SALE. Upon the basis of the representations and warranties herein contained, and subject to the terms and conditions herein set forth, the Company agrees to sell to each Underwriter and each Underwriter agrees, at the time and place herein specified, to purchase from the Company, severally and jointly, at a purchase price of _____% of the principal amount thereof, $__________ aggregate principal amount of the Company's [Debt Securities] (the SECURITIES) having the terms set forth in the Prospectus (as defined in Section 2(b) hereof), in the principal amount set forth opposite the name of such Underwriter in Schedule I attached hereto. The Securities will be issued pursuant to an Indenture dated as of ______________ (including the terms of the Securities to be set forth in an order of the Company thereunder, the INDENTURE) between the Company and _________________, as trustee (the TRUSTEE).

2. REPRESENTATIONS AND WARRANTIES OF COMPANY. The Company represents and warrants to, and covenants and agrees with, the several Underwriters that:

(a) FILING OF REGISTRATION STATEMENT AND ANY PRELIMINARY PROSPECTUS WITH SEC. The Company meets the requirements for use of Form S-3 under the Securities Act of 1933, as amended (the 1933 ACT), and has filed with the Securities and Exchange Commission (the SEC) the Registration Statement (as defined below) and each Preliminary Prospectus (as defined below) relating to the Securities, if any, required to be filed pursuant to Rule 424 under the 1933 Act; and the Registration Statement has been declared effective by the SEC under the 1933 Act and meets the requirements set forth in paragraph (a)(1)(ix) or
(a)(1)(x) of Rule 415 under the 1933 Act and complies in all other material respects with such Rule 415. No stop order suspending the effectiveness of the Registration Statement or any part thereof has been issued under the 1933 Act and no proceedings for that purpose have been instituted or threatened by the SEC, and any request on the part of the SEC for additional information has been complied with by the Company. For purposes of this Agreement, the following terms used herein shall have the following meanings: (i) REGISTRATION STATEMENT shall mean the registration statement on Form S-3 (No. 333-______) filed by the Company with the SEC for the


registration under the 1933 Act of, among other securities, certain securities of the Company, including the Securities, as amended and supplemented to the date of this Agreement and including the exhibits thereto, and shall be deemed to include the Incorporated Documents (as defined below); (ii) INCORPORATED DOCUMENTS shall mean the documents filed by the Company with the SEC under the Securities Exchange Act of 1934, as amended (the 1934 ACT), that are, or are deemed to be, incorporated by reference in the Preliminary Prospectus or the Prospectus pursuant to Item 12 of Form S-3 under the 1933 Act; (iii) PRELIMINARY PROSPECTUS shall mean (A) any prospectus included in the Registration Statement prior to the initial Effective Date (as defined below), or (B) any supplement to the prospectus included in the Registration Statement at the initial Effective Date, as such prospectus may be amended or supplemented as of the date thereof, used in connection with the offering and sale of the Securities (other than making confirmations of sales of the Securities) filed with the SEC pursuant to Rule 424 under the 1933 Act, and shall in each case be deemed to include the Incorporated Documents; and (iv) EFFECTIVE DATE shall mean the later of (x) the date or time that the Registration Statement or any post-effective amendment thereto was declared effective by the SEC under the 1933 Act and (y) the date that the Company's most recent Annual Report on Form 10-K was filed with the SEC under the 1934 Act. For purposes of this Agreement, the words "amend," "amendment," "amended," "supplement" or "supplemented" with respect to the Registration Statement or the Prospectus shall mean (i) amendments or supplements to the Registration Statement or the Prospectus and (ii) Incorporated Documents, in each case filed with the SEC or sent to prospective purchasers of the Securities after the date of this Agreement and prior to the completion of the distribution of the Securities; PROVIDED, HOWEVER, that any supplement to the Prospectus filed with the SEC pursuant to Rule 424(b) under the 1933 Act with respect to an offering of securities of the Company other than the Securities shall not be deemed to be a supplement to, or a part of, the Prospectus.

(b) REGISTRATION STATEMENT; PROSPECTUS; INCORPORATED DOCUMENTS. (i) The Registration Statement, at the Effective Date, any Preliminary Prospectus, at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act and when delivered to you for your use in marketing the Securities, and the Prospectus, at the time it is filed with the SEC pursuant to Rule 424(b) under the 1933 Act and when delivered to you for your use in making confirmations of sales of the Securities, complied and will comply, as the case may be, in all material respects with the applicable requirements of the 1933 Act, the Trust Indenture Act of 1939, as amended (the 1939 ACT), and, in each case, the rules and regulations of the SEC thereunder; (ii) the Registration Statement, at the Effective Date, did not include 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; (iii) the Prospectus, at the time it is filed with the SEC pursuant to Rule 424(b) under the 1933 Act, when delivered to you for your use in making confirmations of sales of the Securities and at the Closing Date (as defined herein), will not and any Preliminary Prospectus, at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act and when delivered to you for your use in marketing the Securities, did not include any 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; and (iv) each Incorporated Document, at the time it was or is filed with the SEC pursuant to the 1934 Act, complied and will comply, as the case may be, in all material respects with the applicable requirements of the 1934 Act and the rules and regulations of the SEC thereunder and, at such times, did not contain and will not contain, as the case may be, an untrue statement of a material fact and did not omit and will not 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; PROVIDED, HOWEVER, that, in the case of clauses (i), (ii) and (iii) above, the Company makes no representation or warranty as to information you furnish

2

in writing to the Company expressly for use in the Prospectus, which for purposes of this Agreement shall be deemed to consist solely of the statements in _________________ (collectively, the UNDERWRITER INFORMATION). For purposes of this Agreement, PROSPECTUS shall mean the prospectus included in the Registration Statement at the initial Effective Date, as such prospectus may be amended or supplemented (including by Incorporated Documents) as of the date hereof, including by a supplement thereto specifying the terms of the Securities and the plan of distribution thereof (the PROSPECTUS SUPPLEMENT), as first filed with the SEC pursuant to Rule 424(b) under the 1933 Act.

(c) INDENTURE. The Indenture has been duly qualified under the 1939 Act, has been duly authorized, executed and delivered by the Company, and constitutes a valid and binding instrument of the Company enforceable against the Company in accordance with its terms, except as may be limited by (i) bankruptcy, insolvency, fraudulent conveyance, reorganization and other similar laws relating to or affecting creditors' rights generally, (ii) general equitable principles (whether considered in a proceeding in equity or at law) and (iii) requirements of reasonableness, good faith and fair dealing (such exceptions, collectively, the EXCEPTIONS); and the Indenture will conform in all material respects to the description thereof contained in the Prospectus.

(d) SECURITIES. The Securities have been duly authorized and, at the Closing Date, will have been duly executed by the Company, and, when authenticated in the manner provided for in the Indenture, issued and delivered against payment therefor pursuant to this Agreement, will constitute valid and binding obligations of the Company enforceable against the Company in accordance with their terms, except as may be limited by the Exceptions, and will be entitled to the benefits of the Indenture; and the Securities will conform in all material respects to the description thereof contained in the Prospectus.

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

(f) DUE INCORPORATION AND QUALIFICATION OF THE COMPANY. The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Missouri, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a material adverse effect on the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole (a MATERIAL ADVERSE EFFECT).

(g) DUE INCORPORATION AND QUALIFICATION OF SUBSIDIARIES. Each subsidiary (as defined in Rule 405 under the 1933 Act) of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; each such subsidiary is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a Material Adverse Effect; and all of the issued and outstanding common stock of each subsidiary of the Company has been duly authorized and validly issued and is

3

fully paid and nonassessable, and all of such common stock (except with regard to 40% of the common stock of Electric Energy, Inc.) is owned by the Company, directly or indirectly, free from liens, encumbrances and defects of title.

(h) MATERIAL CHANGES. Neither the Company nor any of its subsidiaries has sustained since the date of the latest audited consolidated financial statements incorporated by reference in the Prospectus any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as described in the Prospectus; and, since the respective dates as of which information is given in the Prospectus, (i) neither the Company nor any of its subsidiaries has incurred any liabilities or obligations, direct or contingent, or entered into any transactions, not in the ordinary course of business, that are material to the Company and its subsidiaries, taken as a whole, and (ii) there has not been any change in the stockholders' equity (except for regular quarterly dividends, retained earnings and newly issued shares issued pursuant to the Company's dividend reinvestment and stock purchase plan and the Company's 401(k) plans) or long-term debt of the Company or any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole, in each case, otherwise than as described in the Prospectus.

(i) NO CONFLICTS; 1935 ACT ORDER IN FULL FORCE AND EFFECT; NO OTHER CONSENTS REQUIRED. The issue and sale of the Securities by the Company, and the compliance by the Company with all of the provisions of the Securities, the Indenture and this Agreement, and the consummation of the transactions therein and herein contemplated, will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, nor will such action result in any violation of the provisions of the articles of incorporation or by-laws of the Company or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its properties; the execution, delivery and performance of the Indenture, the Securities and this Agreement will not require the approval or consent of any holder or trustee of any debt or other obligations or securities of the Company which will not have been obtained; the SEC has issued its final order under the Public Utility Holding Company Act of 1935, as amended (the 1935 ACT ORDER), authorizing the issuance and sale of the Securities by the Company; the 1935 Act Order is in full force and effect and is sufficient to authorize the transactions contemplated by this Agreement; no other consent, approval, authorization, order, registration, filing or qualification of or with any court or governmental agency or body is required for the issue and sale of the Securities by the Company, or the consummation by the Company of the transactions contemplated by this Agreement or the Indenture, except such as have been obtained under the 1933 Act and the 1939 Act and such consents, approvals, authorizations, orders, registrations, filings or qualifications as may be required under state securities or blue sky laws in connection with the purchase and distribution of the Securities by the Underwriters.

(j) CAPITAL STOCK. The Company has an authorized capitalization as set forth in the Prospectus and all of the issued shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable.

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(k) NO DEFAULTS. Neither the Company nor any of its subsidiaries is
(i) in violation of its articles of incorporation or by-laws, (ii) to the best knowledge of the Company, after due inquiry, in violation of any law, ordinance, administrative or governmental rule or regulation, the violation of which would reasonably be expected to have a Material Adverse Effect, or of any decree of any court or governmental agency or body having jurisdiction over the Company or such subsidiaries, or (iii) in default in the performance or observance of any material obligation, agreement, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which it is a party or by which it or any of its properties may be bound.

(l) LITIGATION. Other than as described in the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject that, if determined adversely to the Company or that subsidiary, would individually or in the aggregate reasonably be expected to have a Material Adverse Effect, and, to the best of the Company's knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others.

(m) FINANCIAL STATEMENTS. The consolidated financial statements of the Company incorporated by reference in the Registration Statement and the Prospectus have been prepared in conformity with generally accepted accounting principles in the United States and fairly present the financial position of the Company as of the dates set forth therein.

(n) INDEPENDENT PUBLIC ACCOUNTANTS. PricewaterhouseCoopers LLP (the ACCOUNTANTS), who have audited certain financial statements of the Company and its subsidiaries, are independent public accountants as required by the 1933 Act and the rules and regulations of the SEC thereunder.

(o) INVESTMENT COMPANY ACT. The Company is not, and, after giving effect to the offering and sale of the Securities, the Company will not be, an "investment company," or an entity "controlled" by an investment company, as such terms are defined in the Investment Company Act of 1940, as amended.

(p) ENVIRONMENTAL MATTERS. Except as described in the Prospectus, each of the Company and its subsidiaries (i) is in compliance with any and all applicable 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 it under applicable Environmental Laws to conduct its business and (iii) is in compliance with all terms and conditions of any such permit, license or approval, except as to clauses (i) and (iii) where such non-compliance with Environmental Laws or failure to comply with the terms and conditions of required permits, licenses or approvals would not, singly or in the aggregate, reasonably be expected to have a Material Adverse Effect.

3. OFFERING; DELIVERY OF SECURITIES.

(a) OFFERING. The Underwriters have advised the Company that they propose to make a public offering of the Securities as soon after the effectiveness of this Agreement as in their judgment is advisable. The Underwriters have further advised the Company that they will offer the Securities to the public at the initial public offering price specified in the Prospectus

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plus accrued interest thereon, if any, from the Closing Date to the date of delivery of the Securities.

(b) DELIVERY OF SECURITIES. Delivery of the Securities to the Underwriters, against payment of the purchase price therefor in immediately available funds by wire transfer, shall be made prior to 1:00 p.m., New York City time, on ___________, 200_ in book-entry form through the facilities of The Depository Trust Company, New York, New York (DTC), or at such other time and date as may be agreed upon in writing by the Company and the Underwriters. Delivery of the documents required by Section 5 hereof with respect to the Securities shall be made at such time and date at the offices of Pillsbury Winthrop LLP (UNDERWRITERS' COUNSEL), or at such other location as may be agreed upon in writing by the Company and the Underwriters. For purposes of this Agreement, CLOSING DATE shall mean the hour and date of such delivery and payment.

The Securities shall be issued in the form of a global certificate registered in the name of "Cede & Co.," as nominee of DTC. For the purpose of expediting checking of the Securities by the Underwriters, the Company agrees to make the Securities available to the Underwriters for such purpose at the offices of DTC (or a custodian thereof) in New York, New York, not later than 1:00 p.m., New York City time, on the business day preceding the Closing Date or at such other time and place as may be agreed upon by the Company and the Underwriters.

4. COVENANTS OF COMPANY. The Company covenants and agrees with the several Underwriters that:

(a) FILING OF PROSPECTUS. The Company will promptly transmit copies of the Prospectus, and any amendments or supplements thereto, to the SEC for filing pursuant to Rule 424(b) under the 1933 Act.

(b) COPIES OF REGISTRATION STATEMENT AND PROSPECTUS; NOTICE OF STOP ORDERS. The Company will deliver to the Underwriters and to Underwriters' Counsel (i) one conformed copy of the Registration Statement as originally filed, including copies of exhibits thereto (other than any exhibits incorporated by reference therein), (ii) conformed copies of any amendments and supplements to the Registration Statement, including copies of the Incorporated Documents (other than exhibits thereto), and (iii) a conformed copy of each consent and certificate included or incorporated by reference in, or filed as an exhibit to, the Registration Statement as so amended and supplemented; the Company will deliver to the Underwriters as soon as practicable after the date of this Agreement as many copies of the Prospectus as the Underwriters may reasonably request for the purposes contemplated by the 1933 Act; the Company will promptly advise the Underwriters of the issuance of any stop order under the 1933 Act with respect to the Registration Statement (as amended or supplemented) or the institution of any proceedings therefor, or the suspension of the qualification of the Securities for sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose, of which the Company shall have received notice or otherwise have knowledge prior to the completion of the distribution of the Securities; and the Company will use its best efforts to prevent the issuance of any such stop order and, if issued, to secure the prompt removal thereof.

(c) FILING OF AMENDMENTS OR SUPPLEMENTS. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will not file any amendment or supplement to the

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Registration Statement, the Prospectus (or any other prospectus relating to the Securities filed pursuant to Rule 424(b) under the 1933 Act that differs from the Prospectus as filed pursuant to such Rule 424(b)) or any Incorporated Document to which the Underwriters or Underwriters' Counsel shall reasonably object.

(d) COMPLIANCE WITH 1933 ACT. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will comply, at its own expense, with all requirements imposed by the 1933 Act, as now and hereafter amended, and by the rules and regulations of the SEC thereunder, as from time to time in force, so far as necessary to permit the continuance of sales of or dealing in the Securities during such period in accordance with the provisions hereof and as contemplated by the Prospectus.

(e) CERTAIN EVENTS AND AMENDMENTS OR SUPPLEMENTS. If, during the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, (i) any event relating to or affecting the Company or of which the Underwriters shall advise the Company in writing shall occur as a result of which, in the opinion of the Underwriters or in the opinion of the Company, the Prospectus as then amended or supplemented would include any 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 or (ii) it shall be necessary to amend or supplement the Registration Statement or the Prospectus to comply with the 1933 Act, the 1934 Act or the 1939 Act or the rules and regulations of the SEC thereunder, the Company will forthwith at its expense prepare and furnish to the Underwriters a reasonable number of copies of such amendment or supplement that will correct such statement or omission or effect such compliance. Neither the Underwriters' consent to, nor the Underwriters' delivery of, any such amendment or supplement prior to the Closing Date shall constitute a waiver of any of the conditions set forth in Section 5 hereof.

(f) BLUE SKY QUALIFICATIONS. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will furnish such proper information as may be lawfully required and otherwise cooperate in qualifying the Securities for offer and sale under the securities or blue sky laws of such jurisdictions as the Underwriters may reasonably designate and will file and make in each year such statements or reports as are or may be reasonably required by the laws of such jurisdictions; PROVIDED, HOWEVER, that the Company shall not be required to qualify as a foreign corporation, qualify as a dealer in securities or file a general consent to service of process under the laws of any jurisdiction.

(g) EARNING STATEMENT. In accordance with Rule 158 under the 1933 Act, the Company will make generally available to its security holders and to holders of the Securities, as soon as practicable, an earning statement (which need not be audited) in reasonable detail covering the 12 months beginning not later than the first day of the month next succeeding the month in which occurred the effective date (within the meaning of Rule 158 under the 1933 Act) of the Registration Statement.

(h) EXCHANGE ACT DOCUMENTS; RATINGS NOTIFICATION. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will file promptly all documents required to be filed with the SEC pursuant to Section
13(a), 13(c), 14 or 15(d) of the 1934 Act; and the Company will promptly notify the Underwriters of any written notice given to the Company by any

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"nationally recognized statistical rating organization" within the meaning of Rule 436(g)(2) under the 1933 Act (a RATING AGENCY) of any intended decrease in any rating of any securities of the Company or of any intended change in any such rating that does not indicate the direction of the possible change of any such rating, in each case by any such Rating Agency.

(i) NO ISSUANCE PERIOD. During the period beginning from the date of this Agreement and continuing to and including the earlier of (i) the termination of trading restrictions on the Securities, as determined by the Underwriters, and (ii) 30 days after the Closing Date, the Company will not, without the prior written consent of the Underwriters, offer for sale, sell or enter into any agreement to sell, or otherwise dispose of, any debt securities (other than short-term debt) of the Company, except for the Securities.

(j) PAYMENT OF EXPENSES. Whether or not any sale of the Securities is consummated, the Company will pay or cause to be paid the following: (i) the fees, disbursements and expenses of counsel for the Company and the Accountants in connection with the registration of the Securities under the 1933 Act and all other expenses in connection with the preparation, printing and filing of the Registration Statement, any Preliminary Prospectus and the Prospectus and amendments or supplements thereto and the mailing and delivering of copies thereof to you and any dealers; (ii) the cost of printing or producing this Agreement, the Indenture, any blue sky memorandum, closing documents (including any compilations thereof) and other documents in connection with the offering, purchase, sale and delivery of the Securities; (iii) all expenses in connection with the qualification of the Securities for offering and sale under state securities laws as provided in Section 4(f) hereof, including the fees and disbursements of Underwriters' Counsel in connection with such qualification and in connection with any such blue sky memorandum; (iv) any fees charged by a Rating Agency for rating the Securities; (v) any filing fees incident to, and the fees and disbursements of Underwriters' Counsel in connection with, any required review by the National Association of Securities Dealers, Inc. of the terms of the sale of the Securities; (vi) the cost of preparing the Securities;
(vii) the fees and disbursements of the Trustee and any agent of the Trustee and the fees and disbursements of their counsel in connection with the Indenture and the Securities; and (viii) all other costs and expenses incident to the performance of the Company's obligations hereunder that are not otherwise specifically provided for in this Section 4(j); but, if for any reason the Securities are not delivered by or on behalf of the Company as provided herein (other than due to a default by the Underwriters), the Company will reimburse the Underwriters for all out-of-pocket expenses, including fees and disbursements of Underwriters' Counsel, reasonably incurred by the Underwriters in making preparations for the purchase, sale and delivery of the Securities, but the Company shall then be under no further liability to the Underwriters with respect to the Securities except as provided in this Section 4(j) and
Section 6 hereof. It is understood that, except as provided in this Section 4(j) and Section 6 hereof, the Underwriters will pay all of their own costs and expenses, including the fees of Underwriters' Counsel and any advertising expenses in connection with any offers the Underwriters may make.

(k) USE OF PROCEEDS. The Company will use the net proceeds from the issuance and sale of the Securities in the manner described in the Prospectus under "Use of Proceeds."

5. CONDITIONS TO UNDERWRITER'S OBLIGATIONS. The obligations of the several Underwriters under this Agreement shall be subject to the condition that all representations and warranties of the Company contained in this Agreement are, at and as of the Closing Date, true

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and correct, the condition that the Company shall have performed all of its obligations hereunder on or prior to the Closing Date and the following additional conditions:

(a) FILING OF PROSPECTUS WITH SEC; NO STOP ORDER; 1935 ACT ORDER IN FULL FORCE AND EFFECT. The Prospectus, and any supplements thereto, shall have been filed with the SEC within the time period prescribed for such filing by Rule 424(b) under the 1933 Act and in accordance with Section 4(a) hereof; all requests for additional information on the part of the SEC shall have been complied with to the reasonable satisfaction of the Underwriters; no stop order suspending the effectiveness of the Registration Statement or any part thereof shall have been issued and no proceeding for that purpose shall have been initiated or threatened by the SEC; and the 1935 Act Order shall be in full force and effect and sufficient to authorize the transactions contemplated by this Agreement.

(b) OPINION OF UNDERWRITERS' COUNSEL. At the Closing Date, Underwriters' Counsel shall have furnished to you an opinion, dated the Closing Date, with respect to the validity of the Securities, the Prospectus and the Registration Statement and such other related matters as you may reasonably request, and Underwriters' Counsel shall have received such documents and information as it may reasonably request to enable it to pass upon such matters. In rendering such opinion, such counsel (A) may rely as to matters involving the application of the laws of the State of Missouri upon the opinion of Steven R. Sullivan, Vice President, General Counsel and Secretary of the Company, rendered pursuant to Section 5(c) hereof and (B) may rely as to matters of fact, to the extent deemed proper, on certificates of responsible officers of the Company and public officials.

(c) OPINION OF COMPANY COUNSEL. At the Closing Date, Steven R. Sullivan, Vice President, General Counsel and Secretary of the Company, shall have furnished to you an opinion, dated the Closing Date, in form and substance satisfactory to you, to the effect that:

(i) the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Missouri, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a Material Adverse Effect;

(ii) each subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation, with all power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; each such subsidiary is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a Material Adverse Effect; and all of the issued and outstanding common stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable, and all of such common stock (except with regard to 40% of the common stock of Electric Energy, Inc.) is owned by the Company, directly or indirectly, free from liens, encumbrances and defects of title;

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(iii) other than as described in the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or such subsidiaries is the subject which, if determined adversely to the Company or such subsidiaries, would individually or in the aggregate reasonably be expected to have a Material Adverse Effect; to the best of such counsel's knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others; and the statements included or incorporated by reference in the Prospectus describing any legal proceedings or material contracts or agreements relating to the Company or any of its subsidiaries fairly summarize such matters;

(iv) this Agreement has been duly authorized, executed and delivered by the Company;

(v) the Securities have been duly authorized and executed by the Company and, when authenticated in the manner provided for in the Indenture, and issued and delivered against payment therefor pursuant to this Agreement, will constitute valid and legally binding obligations of the Company enforceable against the Company in accordance with their terms, except as may be limited by the Exceptions, and will be entitled to the benefits of the Indenture; and the Securities conform in all material respects to the description thereof in the Prospectus;

(vi) the Indenture has been duly authorized, executed and delivered by the Company and, assuming that the Indenture has been duly authorized, executed and delivered by the Trustee, the Indenture will constitute a valid and legally binding instrument of the Company enforceable against the Company in accordance with its terms, except as may be limited by the Exceptions; the Indenture conforms in all material respects to the description thereof in the Prospectus; and the Indenture has been duly qualified under the 1939 Act;

(vii) the issue and sale of the Securities by the Company, and the compliance by the Company with all of the provisions of the Indenture, the Securities and this Agreement, and the consummation of the transactions herein and therein contemplated, will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, nor will such action result in any violation of the provisions of the articles of incorporation or by-laws of the Company or any statute or any order, rule or regulation known to such counsel of any court or governmental agency or body having jurisdiction over the Company or any of its properties; and the execution, delivery and performance of this Agreement, the Securities and the Indenture will not require the approval or consent of any holder or trustee of any debt or other obligations or securities of the Company which will not have been obtained;

(viii) the Company is not, and, after giving effect to the offering and sale of the Securities, the Company will not be, an "investment company," or an entity "controlled" by an investment company, as such terms are defined in the Investment Company Act of 1940, as amended;

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(ix) the SEC has issued the 1935 Act Order authorizing the issuance and sale of the Securities by the Company; the 1935 Act Order is in full force and effect and is sufficient to authorize the transactions contemplated by this Agreement; and no other consent, approval, authorization, order, registration, filing or qualification of or with any court or governmental agency or body is required for the issue and sale of the Securities by the Company, or the consummation by the Company of the transactions contemplated by this Agreement or the Indenture, except such as have been obtained under the 1933 Act and the 1939 Act and such consents, approvals, authorizations, orders, registrations, filings or qualifications as may be required under state securities or blue sky laws in connection with the purchase and distribution of the Securities by the Underwriters; and

(x) the Registration Statement, at the Effective Date, and the Prospectus, at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act (except in each case as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass), complied as to form in all material respects with the requirements of the 1933 Act and the 1939 Act and the respective rules and regulations of the SEC thereunder; each Incorporated Document as originally filed pursuant to the 1934 Act (except as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass) complied as to form when so filed in all material respects with the requirements of the 1934 Act and the rules and regulations of the SEC thereunder; the Registration Statement has become, and on the Closing Date is, effective under the 1933 Act and, to the best of such counsel's knowledge, no proceedings for a stop order with respect thereto are threatened or pending under Section 8 of the 1933 Act; and nothing has come to the attention of such counsel that has caused it to believe that the Registration Statement (except as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass), at the Effective Date, 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 (except as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass), at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act or on the Closing Date, included or includes any 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.

Such opinion shall also state that such counsel has no knowledge of any litigation, pending or threatened, that challenges the validity of the Securities, the Indenture or this Agreement, or that seeks to enjoin the performance of the Company's obligations hereunder or thereunder or that might reasonably be expected to have a Material Adverse Effect except as described in the Prospectus.

In rendering such opinion, such counsel (A) may rely as to matters involving the application of the laws of the State of New York, upon the opinion of Underwriters' Counsel rendered pursuant to Section 5(b) hereof, and (B) may rely as to matters of fact, to the extent deemed proper, on certificates of responsible officers of the Company and public officials. Such counsel's opinion may further state that it is addressed to the Underwriters and is rendered solely for their benefit and may not be relied upon in any manner by any other person (other than Underwriters'

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Counsel as to certain matters involving the application of the laws of the State of Missouri in its opinion to the Underwriters on the date of such opinion) without such counsel's prior written consent.

(d) LETTERS OF ACCOUNTANTS. On the date of this Agreement, and at the Closing Date, the Accountants shall have furnished to the Underwriters letters, dated the date of this Agreement and the Closing Date, respectively, in form and substance satisfactory to the Underwriters, confirming that they are independent accountants within the meaning of the 1933 Act and the rules and regulations of the SEC thereunder with respect to the Company and its subsidiaries and stating in effect that:

(i) in the opinion of the Accountants, the consolidated financial statements and schedules included or incorporated by reference in the Prospectus and audited by them comply as to form in all material respects with the applicable accounting requirements of the 1933 Act and the 1934 Act and the respective rules and regulations of the SEC thereunder; and

(ii) on the basis of a reading of the unaudited consolidated financial statements included or incorporated by reference in the Prospectus and the latest available interim unaudited consolidated financial statements of the Company, the performance of the procedures specified by the American Institute of Certified Public Accountants for a review of any such financial statements as described in Statement on Auditing Standards No. 71, inquiries of officials of the Company responsible for financial and accounting matters and a reading of the minutes of meetings of the stockholders and the Board of Directors of the Company and the Audit Committee thereof through a specified date not more than five days prior to the date of the applicable letter, nothing came to the attention of the Accountants that caused them to believe that: (A) any material modification should be made to the unaudited consolidated financial statements included or incorporated by reference in the Prospectus for them to be in conformity with generally accepted accounting principles or any such financial statements do not comply as to form in all material respects with the applicable accounting requirements of the 1933 Act or the 1934 Act and the respective rules and regulations of the SEC thereunder; (B) for the period from the date of the latest consolidated financial statements included or incorporated by reference in the Prospectus through the date of the most recent available consolidated financial statements of the Company and at a subsequent date not more than five days prior to the date of such letter, there were any decreases in total consolidated net sales, income from operations or net income as compared with the comparable period of the preceding year; or (C) at the date of the most recent available financial statements of the Company and at a subsequent date not more than five days prior to the date of such letter, there was any change in the capital stock of the Company, any increase in long-term debt of the Company, any decrease in consolidated net current assets (working capital) of the Company or any decrease in common shareholders' equity of the Company as compared with the amounts shown in the most recent consolidated balance sheet included or incorporated by reference in the Prospectus, except in all instances for changes, increases or decreases that the Prospectus discloses have occurred or may occur, or for changes, increases or decreases that are described in such letter that are reasonably satisfactory to you.

Such letter shall also cover such other matters as you shall reasonably request, including but not limited to the Company's "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained in the Company's financial statements included or

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incorporated by reference in the Prospectus and any other information of an accounting or financial nature included or incorporated by reference therein that is derived from the accounting records of the Company.

(e) NO MATERIAL CHANGES. (i) Neither the Company nor any of its subsidiaries shall have sustained, since the date of the most recent audited consolidated financial statements included or incorporated by reference in the Prospectus, any loss or interference with their business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth in the Prospectus, and (ii) since the respective dates as of which information is given in the Prospectus, there shall not have been any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole, otherwise than as described in the Prospectus, the effect of which, in any such case described in clause (i) or
(ii), in the judgment of the Underwriters, makes it impracticable or inadvisable to proceed with the public offering or the delivery of the Securities on the terms and in the manner contemplated in the Prospectus or to enforce contracts for the sale of any Securities.

(f) RATINGS; NO DOWNGRADING OF RATINGS OR CREDIT REVIEW. Moody's Investors Service and Standard & Poor's shall have publicly assigned to the Securities ratings of __ and __, respectively, which ratings shall be in full force and effect at the Closing Date; and, on or after the date of this Agreement, (i) no downgrading shall have occurred in the rating (or expected rating) accorded any of the Company's securities by any Rating Agency and (ii) no Rating Agency shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating (or expected rating) of any of the Company's securities.

(g) NONOCCURRENCE OF CERTAIN EVENTS. On or after the date of this Agreement, there shall not have occurred any of the following: (i) a suspension or limitation of trading in securities of the Company or generally on the New York Stock Exchange, the American Stock Exchange or the Nasdaq Stock Market or any setting of minimum or maximum prices for trading thereon; (ii) a general moratorium on commercial banking activities in New York, New York declared by the relevant authorities or a material disruption in commercial banking or securities settlement or clearance services in the United States; (iii) the outbreak or escalation of hostilities involving the United States or the declaration by the United States of a national emergency or war; or (iv) the occurrence of any other calamity or crisis or any change in financial, political or economic conditions in the United States or elsewhere, which, in the case of either clause (iii) or (iv), in the judgment of the Underwriters, makes it impracticable or inadvisable to proceed with the public offering or the delivery of the Securities on the terms and in the manner contemplated in the Prospectus or to enforce contracts for the sale of any of the Securities.

(h) OFFICERS' CERTIFICATE. At the Closing Date, the Company shall have furnished or caused to be furnished to the Underwriters a certificate, dated the Closing Date, of (i) the chief executive officer, the President or any Senior Vice President of the Company and (ii) the Treasurer of the Company in which such officers shall state that the representations and warranties of the Company in this Agreement are true and correct in all material respects at and as of the Closing Date, and that the Company has complied with all agreements and has satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date and that, subsequent to the respective dates as of which information is given in the Prospectus, there has been no material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial

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position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole, otherwise than as described in the Prospectus.

(i) OTHER DOCUMENTS AND CERTIFICATES. At the Closing Date, Underwriters' Counsel shall have been furnished with all such documents, certificates and opinions as Underwriters' Counsel may reasonably request and that are customary for transactions of a similar nature, and of which the Company has been notified in writing prior to the date hereof, in order to evidence the accuracy and completeness of any of the representations, warranties, certificates or other written statements of the Company provided to the Underwriters pursuant to this Agreement, the performance of any of the covenants of the Company, or the fulfillment of any of the conditions herein contained. All proceedings taken by the Company at or prior to the Closing Date in connection with the authorization, issuance and sale of the Securities as contemplated by this Agreement, including, without limitation, the execution of the Indenture, the Securities and this Agreement, shall be reasonably satisfactory in form and substance to the Underwriters and Underwriters' Counsel.

In case any of the conditions specified above in this Section 5 shall not have been fulfilled, this Agreement may be terminated by you upon mailing or otherwise delivering written notice thereof to the Company. Any such termination shall be without liability of either party to the other party except as otherwise provided in Section 4(j) hereof and except for any liability under
Section 6 hereof.

6. INDEMNIFICATION AND CONTRIBUTION

(a) INDEMNIFICATION BY COMPANY. The Company will indemnify and hold harmless each Underwriter against any losses, claims, damages, liabilities or expenses, as and when incurred, to which such Underwriter may become subject, joint or several, under the 1933 Act or otherwise, insofar as such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof), arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities, or any amendment or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and will promptly reimburse such Underwriter for any reasonable expenses (including reasonable fees and expenses for no more than one law firm for the Underwriters) when and as incurred by such Underwriter in connection with investigating or defending any such action or claim; PROVIDED, HOWEVER, that the Company shall not be liable in any such case to an Underwriter to the extent that any such loss, claim, damage, liability or expense arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities or any such amendment or supplement thereto in reliance upon and in conformity with the Underwriter Information.

(b) INDEMNIFICATION BY THE UNDERWRITERS. Each Underwriter, severally, will indemnify and hold harmless the Company against any losses, claims, damages, liabilities or expenses to which the Company may become subject, under the 1933 Act or otherwise, insofar as such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities or any amendment or supplement thereto, or arise out of are based upon the omission or alleged omission to state therein a material fact required

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to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities or any such amendment or supplement, in reliance upon and in conformity with the Underwriter Information, and will reimburse the Company for any reasonable expenses (including reasonable fees and expenses for no more than one law firm for the Company) when and as incurred by the Company in connection with investigating or defending any such action or claim.

(c) GENERAL. Promptly after receipt by an indemnified party under
Section 6(a) or 6(b) hereof of notice of the commencement of any action, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under Section 6(a) or 6(b) hereof, notify such indemnifying party in writing of the commencement thereof, but the omission so to notify such indemnifying party shall not relieve such indemnifying party from any liability except to the extent that it has been prejudiced in any material respect by such failure or from any liability that it may have to any such indemnified party otherwise than under Section 6(a) or 6(b) hereof. In case any such action shall be brought against any such indemnified party and it shall notify such indemnifying party of the commencement thereof, such indemnifying party shall be entitled to participate therein and, to the extent that it shall wish, jointly with any other indemnifying party under Section 6(a) or (b) hereof similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party (who shall not, except with the consent of such indemnified party, be counsel to such indemnifying party), and, after notice from such indemnifying party to such indemnified party of its election so to assume the defense thereof, such indemnifying party shall not be liable to such indemnified party under Section 6(a) or 6(b) hereof for any legal expenses of other counsel or any other expenses, in each case subsequently incurred by such indemnified party, in connection with the defense thereof other than reasonable costs of investigation. Notwithstanding the foregoing, the indemnified party shall have the right to employ separate counsel at the indemnifying party's expense and to control its defense of such action if (i) the indemnifying party and the indemnified party agree to the retention of that counsel, (ii) the indemnifying party does not assume the defense of such action in a timely manner or (iii) the indemnified party reasonably objects to such assumption on the ground that there may be legal defenses available to it that are different from or in addition to those available to the indemnifying party or another indemnified party. No indemnifying party shall, without the written consent of the indemnified party, effect the settlement or compromise of, or consent to the entry of any judgment with respect to, any pending or threatened action or claim in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified party is an actual or potential party to such action or claim) unless such settlement, compromise or judgment (x) includes an unconditional release of the indemnified party from all liability arising out of such action or claim and (y) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of any indemnified party.

(d) CONTRIBUTION. If the indemnification provided for in this
Section 6 is unavailable to or insufficient to hold harmless an indemnified party under Section 6(a) or 6(b) hereof in respect of any losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) referred to therein, then each indemnifying party under Section 6(a) or 6(b) hereof shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other hand from the offering of the Securities. If, however, the allocation provided by the immediately preceding sentence is not permitted by

15

applicable law, then each such indemnifying party shall contribute to such amount paid or payable by such indemnified party in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company on the one hand and the Underwriters on the other hand in connection with the statements or omissions that resulted in such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof), 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 shall be deemed to be in the same proportion as the total net proceeds from such offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions the Underwriters received. 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 the Underwriters and the parties' relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 6(d) were determined by PRO RATA allocation or by any other method of allocation that does not take account of the equitable considerations referred to above in this
Section 6(d). The amount paid or payable by such an indemnified party as a result of the losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) referred to above in this Section 6(d) shall be deemed to include any legal or other expenses incurred by such indemnified party in connection with investigating or defending any such action or claim. The obligations of the Underwriters to contribute hereunder are several and not joint. Notwithstanding the provisions of this Section 6(d), no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Securities underwritten by such Underwriter 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 1933 Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

(e) SCOPE OF OBLIGATIONS. The obligations of the Company under this
Section 6 shall be in addition to any liability that the Company may otherwise have and shall extend, upon the same terms and conditions, to each officer, director, employee, agent or other representative and to each person, if any, who controls each Underwriter within the meaning of the 1933 Act or the 1934 Act; and the obligations of the Underwriters under this Section 6 shall be in addition to any liability that the Underwriters may otherwise have and shall extend, upon the same terms and conditions, to each officer, director, employee, agent or other representative and to each person, if any, who controls the Company within the meaning of the 1933 Act or the 1934 Act.

7. REPRESENTATIONS, WARRANTIES AND AGREEMENTS TO SURVIVE DELIVERY. The respective indemnities, agreements, representations, warranties and other statements of the Company and the Underwriters, as set forth in this Agreement or made by or on behalf of the Company or the Underwriters, respectively, pursuant to this Agreement, shall remain in full force and effect, regardless of any investigation (or any statement as to the results thereof) made by or on behalf of the Underwriters, any of their officers, directors, employees, agents or other representatives or controlling persons, or the Company, any officer or director of the Company who signed the Registration Statement or any controlling person of the Company, and shall survive delivery of and payment for the Securities.

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8. 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 ___________________ at the address set forth on the first page of this Agreement, attention of _______________; and notices to the Company shall be directed to Ameren Corporation, 1901 Chouteau Avenue, St. Louis, Missouri 63103, attention of Treasurer.

9. DEFAULT BY AN UNDERWRITER. If any Underwriter shall fail at the Closing Date to purchase the Securities which it is obligated to purchase under this Agreement (the DEFAULTED SECURITIES), the non-defaulting Underwriter or Underwriters shall have the right, but not the obligation, within 24 hours thereafter, to purchase, or to make arrangements for the appointment of another purchaser to purchase, the Defaulted Securities in such amounts as may be agreed upon and upon the terms herein set forth. If, however, the non-defaulting Underwriter or Underwriters shall not have completed such arrangements within such 24-hour period, then this Agreement shall terminate without liability on the part of the non-defaulting Underwriter or Underwriters. No action taken pursuant hereto shall relieve any defaulting Underwriter from liability in respect of its default. In the event of any such default which does not result in a termination of this Agreement, either the non-defaulting Underwriter or Underwriters or the Company shall have the right to postpone the Closing Date for a period not exceeding 7 days in order to effect any required changes in the Registration Statement, the Prospectus or in any other documents or arrangements related thereto. The term "Underwriter" for purposes of this Agreement includes any such person substituted for the defaulting Underwriter. Notwithstanding any termination pursuant to this Section 9, the provisions of Sections 4(j), 6, 7 and 10 hereof shall remain in effect.

10. MISCELLANEOUS. The rights and duties of the parties to this Agreement shall, pursuant to New York General Obligations Law Section 5-1401, be governed by the law of the State of New York. This Agreement shall be binding upon, and inure solely to the benefit of, the Company and the Underwriters except to the extent provided in Section 6(e) hereof, and their respective heirs, executors, administrators, successors and assigns, and no other person shall acquire or have any right under or by virtue of this Agreement. No person who purchases any of the Securities from the Underwriters shall be deemed a successor or assign by reason merely of such purchase. This Agreement may be executed by any one or more of the parties hereto in any number of counterparts, each of which shall be deemed to be an original, but all such respective counterparts shall together constitute one and the same instrument. The word "or" shall not be exclusive, and all references in this Agreement to the words "herein," "hereof," "hereunder" and other words of similar import refer to this Agreement as a whole and not to any particular Section or subdivision hereof, and the captions to such Sections and subdivisions are for convenience only and shall not affect the construction hereof.

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If the foregoing is in accordance with your understanding, please sign and return to the Company the enclosed duplicate hereof, whereupon this Agreement will become a binding agreement between the Company and the Underwriters in accordance with its terms.

Very truly yours,

AMEREN CORPORATION

By:

Name:


Title:

Accepted as of the date hereof:

[Names of Underwriters]

BY: [LEAD UNDERWRITER]

By:
Name:
Title:

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SCHEDULE I

                                                PRINCIPAL
                                                AMOUNT OF
NAME OF UNDERWRITER                             SECURITIES
--------------------------------------------  --------------
                                               $







     TOTAL..................................   $
                                               =====


EXHIBIT 1.3

AMEREN CORPORATION


SHARES OF COMMON STOCK

UNDERWRITING AGREEMENT

____________, 200_

[Names of Underwriters]
c/o [Name of Lead Underwriter]
[Address]

Ladies and Gentlemen:

Ameren Corporation, a Missouri corporation (the COMPANY), hereby confirms its agreement with you, as underwriters (the "Underwriters"), with respect to the issuance and sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of the respective numbers of shares of Common Stock, $.01 par value per share, of the Company (COMMON Stock) set forth in Schedule I attached hereto, and with respect to the grant by the Company to the Underwriters, acting severally and not jointly, of the option described in
Section 1(b) hereof to purchase all or any part of _______ additional shares of Common Stock to cover over-allotments, if any. The aforesaid _______ shares of Common Stock (the INITIAL SECURITIES) to be purchased by the Underwriters and all or any part of the ______ shares of Common Stock subject to the option described in Section 1(b) hereof (the OPTION SECURITIES) are hereinafter called, collectively, the SECURITIES.

1. PURCHASE AND SALE.

(a) INITIAL SECURITIES. Upon the basis of the representations and warranties herein contained, and subject to the terms and conditions herein set forth, the Company agrees to sell to each Underwriter and each Underwriter agrees, at the time and place herein specified, to purchase from the Company, severally and jointly, at the price per share set forth in Schedule II attached hereto, the number of Initial Securities set forth in Schedule I opposite the name of such Underwriter.

(b) OPTION SECURITIES. In addition, on the basis of the representations and warranties herein contained, and subject to the terms and conditions herein set forth, the Company hereby grants an option to the Underwriters, severally and not jointly, to purchase up to an additional _______ shares of Common Stock at the price per share set forth in Schedule II, less an amount per share equal to any dividends or distributions declared by the Company and payable on the Initial Securities but not payable on the Option Securities. The option hereby granted will expire 30 days after the date hereof and may be exercised in whole or in part, from time to time, only for the purpose of covering over-allotments which may be made in connection with the offering and distribution of the Initial Securities upon written notice by the Underwriters to the Company on any business day during such 30-day period setting forth the number of Option Securities as to which the several Underwriters are exercising the option and


the time and date of payment and delivery for such Option Securities. Any such time and date of delivery (each, a DATE OF DELIVERY) shall be determined by the Underwriters, but shall not be later than seven full business days after the exercise of said option, nor in any event prior to the Closing Time (as defined herein). If the option is exercised as to all or any portion of the Option Securities, each of the Underwriters, acting severally and not jointly, will purchase that proportion of the total number of Option Securities then being purchased which the number of Initial Securities set forth in Schedule I opposite the name of such Underwriter bears to the total number of Initial Securities, subject in each case to such adjustments as the Underwriters in their discretion shall make to eliminate any sales or purchases of fractional shares. For purposes of this Agreement, "business day" means any day on which the New York Stock Exchange, Inc. (the NYSE) is open for bidding.

2. REPRESENTATIONS AND WARRANTIES OF COMPANY. The Company represents and warrants to the several Underwriters as of the date hereof, as of the Closing Date referred to in Section 3(b) hereof and as of each Date of Delivery, if any, referred to in Section 1(b) hereof, and covenants and agrees with the several Underwriters that:

(a) FILING OF REGISTRATION STATEMENT AND ANY PRELIMINARY PROSPECTUS WITH SEC. The Company meets the requirements for use of Form S-3 under the Securities Act of 1933, as amended (the 1933 ACT), and has filed with the Securities and Exchange Commission (the SEC) the Registration Statement (as defined below) and each Preliminary Prospectus (as defined below) relating to the Securities, if any, required to be filed pursuant to Rule 424 under the 1933 Act; and the Registration Statement has been declared effective by the SEC under the 1933 Act and meets the requirements set forth in paragraph (a)(1)(ix) or
(a)(1)(x) of Rule 415 under the 1933 Act and complies in all other material respects with such Rule 415. No stop order suspending the effectiveness of the Registration Statement or any part thereof has been issued under the 1933 Act and no proceedings for that purpose have been instituted or threatened by the SEC, and any request on the part of the SEC for additional information has been complied with by the Company. For purposes of this Agreement, the following terms used herein shall have the following meanings: (i) REGISTRATION STATEMENT shall mean the registration statement on Form S-3 (No. 333-______) filed by the Company with the SEC for the registration under the 1933 Act of, among other securities, certain securities of the Company, including the Securities, as amended and supplemented to the date of this Agreement and including the exhibits thereto, and shall be deemed to include the Incorporated Documents (as defined below); (ii) INCORPORATED DOCUMENTS shall mean the documents filed by the Company with the SEC under the Securities Exchange Act of 1934, as amended (the 1934 ACT), that are, or are deemed to be, incorporated by reference in the Preliminary Prospectus or the Prospectus pursuant to Item 12 of Form S-3 under the 1933 Act; (iii) PRELIMINARY PROSPECTUS shall mean (A) any prospectus included in the Registration Statement prior to the initial Effective Date (as defined below), or (B) any supplement to the prospectus included in the Registration Statement at the initial Effective Date, as such prospectus may be amended or supplemented as of the date thereof, used in connection with the offering and sale of the Securities (other than making confirmations of sales of the Securities) filed with the SEC pursuant to Rule 424 under the 1933 Act, and shall in each case be deemed to include the Incorporated Documents; and (iv) EFFECTIVE DATE shall mean the later of (x) the date or time that the Registration Statement or any post-effective amendment thereto was declared effective by the SEC under the 1933 Act and (y) the date that the Company's most recent Annual Report on Form 10-K was filed with the SEC under the 1934 Act. For purposes of this Agreement, the words "amend," "amendment," "amended," "supplement" or "supplemented" with respect to the Registration Statement or the Prospectus shall mean (i) amendments or supplements to the Registration Statement or the Prospectus and (ii) Incorporated Documents, in each case filed with the SEC or sent to

2

prospective purchasers of the Securities after the date of this Agreement and prior to the completion of the distribution of the Securities; PROVIDED, HOWEVER, that any supplement to the Prospectus filed with the SEC pursuant to Rule 424(b) under the 1933 Act with respect to an offering of securities of the Company other than the Securities shall not be deemed to be a supplement to, or a part of, the Prospectus.

(b) REGISTRATION STATEMENT; PROSPECTUS; INCORPORATED DOCUMENTS. (i) The Registration Statement, at the Effective Date, any Preliminary Prospectus, at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act and when delivered to you for your use in marketing the Securities, and the Prospectus, at the time it is filed with the SEC pursuant to Rule 424(b) under the 1933 Act and when delivered to you for your use in making confirmations of sales of the Securities, complied and will comply, as the case may be, in all material respects with the applicable requirements of the 1933 Act, the Trust Indenture Act of 1939, as amended (the 1939 ACT), and, in each case, the rules and regulations of the SEC thereunder; (ii) the Registration Statement, at the Effective Date, did not include 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; (iii) the Prospectus, at the time it is filed with the SEC pursuant to Rule 424(b) under the 1933 Act, when delivered to you for your use in making confirmations of sales of the Securities and at the Closing Date (and, if any Option Securities are purchased, at each Date of Delivery), will not and any Preliminary Prospectus, at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act and when delivered to you for your use in marketing the Securities, did not include any 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; and (iv) each Incorporated Document, at the time it was or is filed with the SEC pursuant to the 1934 Act, complied and will comply, as the case may be, in all material respects with the applicable requirements of the 1934 Act and the rules and regulations of the SEC thereunder and, at such times, did not contain and will not contain, as the case may be, an untrue statement of a material fact and did not omit and will not 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; PROVIDED, HOWEVER, that, in the case of clauses (i), (ii) and (iii) above, the Company makes no representation or warranty as to information you furnish in writing to the Company expressly for use in the Prospectus, which for purposes of this Agreement shall be deemed to consist solely of the statements in ______________ (collectively, the UNDERWRITER INFORMATION). For purposes of this Agreement, PROSPECTUS shall mean the prospectus included in the Registration Statement at the initial Effective Date, as such prospectus may be amended or supplemented (including by Incorporated Documents) as of the date hereof, including by a supplement thereto specifying the terms of the Securities and the plan of distribution thereof (the PROSPECTUS SUPPLEMENT), as first filed with the SEC pursuant to Rule 424(b) under the 1933 Act.

(c) SECURITIES. The Securities have been duly authorized by the Company for issuance and sale to the Underwriters pursuant to this Agreement and, when issued and delivered by the Company pursuant to this Agreement against payment of the consideration set forth herein, will be validly issued, fully paid and nonassessable; the Common Stock conforms in all material respects to all statements relating thereto contained in the Prospectus and such description conforms to the rights set forth in the instruments defining the same; no holder of the Securities will be subject to personal liability solely by reason of being such a holder; and the issuance of the Securities is not subject to the preemptive or other similar rights of any securityholder of the Company or any of its subsidiaries.

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

(e) DUE INCORPORATION AND QUALIFICATION OF THE COMPANY. The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Missouri, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a material adverse effect on the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole (a MATERIAL ADVERSE EFFECT).

(f) DUE INCORPORATION AND QUALIFICATION OF SUBSIDIARIES. Each subsidiary (as defined in Rule 405 under the 1933 Act) of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; each such subsidiary is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a Material Adverse Effect; and all of the issued and outstanding common stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable, and all of such common stock (except with regard to 40% of the common stock of Electric Energy, Inc.) is owned by the Company, directly or indirectly, free from liens, encumbrances and defects of title.

(g) MATERIAL CHANGES. Neither the Company nor any of its subsidiaries has sustained since the date of the latest audited consolidated financial statements incorporated by reference in the Prospectus any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as described in the Prospectus; and, since the respective dates as of which information is given in the Prospectus, (i) neither the Company nor any of its subsidiaries has incurred any liabilities or obligations, direct or contingent, or entered into any transactions, not in the ordinary course of business, that are material to the Company and its subsidiaries, taken as a whole, and (ii) there has not been any change in the stockholders' equity (except for regular quarterly dividends, retained earnings and newly issued shares issued pursuant to the Company's dividend reinvestment and stock purchase plan and the Company's 401(k) plans) or long-term debt of the Company or any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole, in each case, otherwise than as described in the Prospectus.

(h) NO CONFLICTS; 1935 ACT ORDER IN FULL FORCE AND EFFECT; NO OTHER CONSENTS REQUIRED. The issue and sale of the Securities by the Company, and the compliance by the Company with all of the provisions of this Agreement, and the consummation of the transactions herein contemplated, will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is

4

a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, nor will such action result in any violation of the provisions of the articles of incorporation or by-laws of the Company or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its properties; the execution, delivery and performance of this Agreement will not require the approval or consent of any holder or trustee of any debt or other obligations or securities of the Company which will not have been obtained; the SEC has issued its final order under the Public Utility Holding Company Act of 1935, as amended (the 1935 ACT ORDER), authorizing the issuance and sale of the Securities by the Company; the 1935 Act Order is in full force and effect and is sufficient to authorize the transactions contemplated by this Agreement; no other consent, approval, authorization, order, registration, filing or qualification of or with any court or governmental agency or body is required for the issue and sale of the Securities by the Company, or the consummation by the Company of the transactions contemplated by this Agreement, except such as have been obtained under the 1933 Act and the 1939 Act and such consents, approvals, authorizations, orders, registrations, filings or qualifications as may be required under state securities or blue sky laws in connection with the purchase and distribution of the Securities by the Underwriters.

(i) CAPITAL STOCK. The Company has an authorized capitalization as set forth in the Prospectus and all of the issued shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable.

(j) NO DEFAULTS. Neither the Company nor any of its subsidiaries is
(i) in violation of its articles of incorporation or by-laws, (ii) to the best knowledge of the Company, after due inquiry, in violation of any law, ordinance, administrative or governmental rule or regulation, the violation of which would reasonably be expected to have a Material Adverse Effect, or of any decree of any court or governmental agency or body having jurisdiction over the Company or such subsidiaries, or (iii) in default in the performance or observance of any material obligation, agreement, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which it is a party or by which it or any of its properties may be bound.

(k) LITIGATION. Other than as described in the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject that, if determined adversely to the Company or that subsidiary, would individually or in the aggregate reasonably be expected to have a Material Adverse Effect, and, to the best of the Company's knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others.

(l) FINANCIAL STATEMENTS. The consolidated financial statements of the Company incorporated by reference in the Registration Statement and the Prospectus have been prepared in conformity with generally accepted accounting principles in the United States and fairly present the financial position of the Company as of the dates set forth therein.

(m) INDEPENDENT PUBLIC ACCOUNTANTS. PricewaterhouseCoopers LLP (the ACCOUNTANTS), who have audited certain financial statements of the Company and its subsidiaries, are independent public accountants as required by the 1933 Act and the rules and regulations of the SEC thereunder.

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(n) INVESTMENT COMPANY ACT. The Company is not, and, after giving effect to the offering and sale of the Securities, the Company will not be, an "investment company," or an entity "controlled" by an investment company, as such terms are defined in the Investment Company Act of 1940, as amended.

(o) ENVIRONMENTAL MATTERS. Except as described in the Prospectus, each of the Company and its subsidiaries (i) is in compliance with any and all applicable 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 it under applicable Environmental Laws to conduct its business and (iii) is in compliance with all terms and conditions of any such permit, license or approval, except as to clauses (i) and (iii) where such non-compliance with Environmental Laws or failure to comply with the terms and conditions of required permits, licenses or approvals would not, singly or in the aggregate, reasonably be expected to have a Material Adverse Effect.

3. OFFERING; PAYMENT AND DELIVERY OF SECURITIES.

(a) OFFERING. The Underwriters have advised the Company that they propose to make a public offering of the Securities as soon after the effectiveness of this Agreement as in their judgment is advisable. The Underwriters have further advised the Company that they will offer the Securities to the public at the initial public offering price per share for the Securities set forth in Schedule II.

(b) PAYMENT AND DELIVERY OF SECURITIES. Payment of the purchase price for, and delivery of certificates for, the Initial Securities shall be made at the offices of Pillsbury Winthrop LLP (UNDERWRITERS' COUNSEL), One Battery Park Plaza, New York, New York 10004, or at such other place as shall be agreed upon by the Underwriters and the Company, at 9:00 a.m. (New York City time) on the third (fourth, if the pricing occurs after 4:30 p.m. (New York City time) on any given day) business day after the date hereof, or such other time not later than ten business days after such date as shall be agreed upon by the Underwriters and the Company (such time and date of payment and delivery being herein called the CLOSING DATE).

In addition, in the event that any or all of the Option Securities are purchased by the Underwriters, payment of the purchase price for, and delivery of certificates for, such Option Securities shall be made at the above-mentioned offices, or at such other place as shall be agreed upon by the Underwriters and the Company, on each Date of Delivery as specified in the written notice from the Underwriters to the Company.

Payment shall be made to the Company by wire transfer of immediately available funds to a bank account designated by the Company, against delivery to ______________ for the respective accounts of the Underwriters of certificates for the Securities to be purchased by them. It is understood that each Underwriter has authorized ____________ to execute this Agreement on its behalf and, for its account, to accept delivery of, receipt for, and make payment of the purchase price for, the Initial Securities and the Option Securities, if any, which it has agreed to purchase. _______________, individually and not as representative of the Underwriters, may (but shall not be obligated to) make payment of the purchase price for the Initial Securities or the Option Securities, if any, to be purchased by any Underwriter whose funds have not been received by the Closing Date or any Date of Delivery, as the case may be, but such payment shall not relieve such Underwriter from its obligations hereunder.

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Certificates for the Initial Securities and the Option Securities, if any, shall be in such denominations and registered in such names as the Underwriters may request in writing at least one full business day before the Closing Date or any Date of Delivery, as the case may be. The certificates for the Initial Securities and the Option Securities, if any, will be made available for examination and packaging by the Underwriters in New York City not later than 10:00 a.m. (New York City time) on the business day prior to the Closing Date or any Date of Delivery, as the case may be.

4. COVENANTS OF COMPANY. The Company covenants and agrees with the several Underwriters that:

(a) FILING OF PROSPECTUS. The Company will promptly transmit copies of the Prospectus, and any amendments or supplements thereto, to the SEC for filing pursuant to Rule 424(b) under the 1933 Act.

(b) COPIES OF REGISTRATION STATEMENT AND PROSPECTUS; NOTICE OF STOP ORDERS. The Company will deliver to the Underwriters and to Underwriters' Counsel (i) one conformed copy of the Registration Statement as originally filed, including copies of exhibits thereto (other than any exhibits incorporated by reference therein), (ii) conformed copies of any amendments and supplements to the Registration Statement, including copies of the Incorporated Documents (other than exhibits thereto), and (iii) a conformed copy of each consent and certificate included or incorporated by reference in, or filed as an exhibit to, the Registration Statement as so amended and supplemented; the Company will deliver to the Underwriters as soon as practicable after the date of this Agreement as many copies of the Prospectus as the Underwriters may reasonably request for the purposes contemplated by the 1933 Act; the Company will promptly advise the Underwriters of the issuance of any stop order under the 1933 Act with respect to the Registration Statement (as amended or supplemented) or the institution of any proceedings therefor, or the suspension of the qualification of the Securities for sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose, of which the Company shall have received notice or otherwise have knowledge prior to the completion of the distribution of the Securities; and the Company will use its best efforts to prevent the issuance of any such stop order and, if issued, to secure the prompt removal thereof.

(c) FILING OF AMENDMENTS OR SUPPLEMENTS. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will not file any amendment or supplement to the Registration Statement, the Prospectus (or any other prospectus relating to the Securities filed pursuant to Rule 424(b) under the 1933 Act that differs from the Prospectus as filed pursuant to such Rule
424(b)) or any Incorporated Document to which the Underwriters or Underwriters' Counsel shall reasonably object.

(d) COMPLIANCE WITH 1933 ACT. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will comply, at its own expense, with all requirements imposed by the 1933 Act, as now and hereafter amended, and by the rules and regulations of the SEC thereunder, as from time to time in force, so far as necessary to permit the continuance of sales of or dealing in the Securities during such period in accordance with the provisions hereof and as contemplated by the Prospectus.

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(e) CERTAIN EVENTS AND AMENDMENTS OR SUPPLEMENTS. If, during the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, (i) any event relating to or affecting the Company or of which the Underwriters shall advise the Company in writing shall occur as a result of which, in the opinion of the Underwriters or in the opinion of the Company, the Prospectus as then amended or supplemented would include any 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 or (ii) it shall be necessary to amend or supplement the Registration Statement or the Prospectus to comply with the 1933 Act, the 1934 Act or the 1939 Act or the rules and regulations of the SEC thereunder, the Company will forthwith at its expense prepare and furnish to the Underwriters a reasonable number of copies of such amendment or supplement that will correct such statement or omission or effect such compliance. Neither the Underwriters' consent to, nor the Underwriters' delivery of, any such amendment or supplement prior to the Closing Date shall constitute a waiver of any of the conditions set forth in Section 5 hereof.

(f) BLUE SKY QUALIFICATIONS. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will furnish such proper information as may be lawfully required and otherwise cooperate in qualifying the Securities for offer and sale under the securities or blue sky laws of such jurisdictions as the Underwriters may reasonably designate and will file and make in each year such statements or reports as are or may be reasonably required by the laws of such jurisdictions; PROVIDED, HOWEVER, that the Company shall not be required to qualify as a foreign corporation, qualify as a dealer in securities or file a general consent to service of process under the laws of any jurisdiction.

(g) EARNING STATEMENT. In accordance with Rule 158 under the 1933 Act, the Company will make generally available to its security holders and to holders of the Securities, as soon as practicable, an earning statement (which need not be audited) in reasonable detail covering the 12 months beginning not later than the first day of the month next succeeding the month in which occurred the effective date (within the meaning of Rule 158 under the 1933 Act) of the Registration Statement.

(h) EXCHANGE ACT DOCUMENTS; RATINGS NOTIFICATION. During the period when a prospectus relating to any of the Securities is required to be delivered under the 1933 Act by any Underwriter or any dealer, the Company will file promptly all documents required to be filed with the SEC pursuant to Section
13(a), 13(c), 14 or 15(d) of the 1934 Act; and the Company will promptly notify the Underwriters of any written notice given to the Company by any "nationally recognized statistical rating organization" within the meaning of Rule 436(g)(2) under the 1933 Act (a RATING AGENCY) of any intended decrease in any rating of any securities of the Company or of any intended change in any such rating that does not indicate the direction of the possible change of any such rating, in each case by any such Rating Agency.

(i) RESTRICTION ON SALE OF SECURITIES. During a period of 90 days from the date of the Prospectus, the Company will not, without the prior written consent of ___________, directly or indirectly, (i) 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 or otherwise transfer or dispose of any share of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or file any registration statement under the 1933 Act with respect to any of the foregoing or (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the

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economic consequence of ownership of the Common Stock, whether any such swap or transaction is to be settled by delivery of Common Stock or other securities, in cash or otherwise. The foregoing sentence shall not apply to (A) the Securities to be sold hereunder, (B) any shares of Common Stock issued by the Company upon the exercise of an option or warrant or the conversion of a security outstanding on the date hereof, (C) any shares of Common Stock issued or options to purchase Common Stock granted pursuant to existing employee benefit plans of the Company or (D) any shares of Common Stock issued pursuant to any nonemployee director stock plan or dividend reinvestment and stock repurchase plan in effect on the date of the filing of the Registration Statement.

(j) PAYMENT OF EXPENSES. Whether or not any sale of the Securities is consummated, the Company will pay or cause to be paid the following: (i) the fees, disbursements and expenses of counsel for the Company and the Accountants in connection with the registration of the Securities under the 1933 Act and all other expenses in connection with the preparation, printing and filing of the Registration Statement, any Preliminary Prospectus and the Prospectus and amendments or supplements thereto and the mailing and delivering of copies thereof to you and any dealers; (ii) the cost of printing or producing this Agreement, any blue sky memorandum, closing documents (including any compilations thereof) and other documents in connection with the offering, purchase, sale and delivery of the Securities; (iii) all expenses in connection with the qualification of the Securities for offering and sale under state securities laws as provided in Section 4(f) hereof, including the fees and disbursements of Underwriters' Counsel in connection with such qualification and in connection with any such blue sky memorandum; (iv) the fees and expenses incurred in connection with the listing of the Securities on the NYSE; (v) any filing fees incident to, and the fees and disbursements of Underwriters' Counsel in connection with, any required review by the National Association of Securities Dealers, Inc. of the terms of the sale of the Securities; (vi) the cost of preparing the Securities; (vii) the fees and disbursements of any transfer agent or registrar for the Securities; and (viii) all other costs and expenses incident to the performance of the Company's obligations hereunder that are not otherwise specifically provided for in this Section 4(j); but, if for any reason the Securities are not delivered by or on behalf of the Company as provided herein (other than due to a default by the Underwriters), the Company will reimburse the Underwriters for all out-of-pocket expenses, including fees and disbursements of Underwriters' Counsel, reasonably incurred by the Underwriters in making preparations for the purchase, sale and delivery of the Securities, but the Company shall then be under no further liability to the Underwriters with respect to the Securities except as provided in this Section 4(j) and Section 6 hereof. It is understood that, except as provided in this
Section 4(j) and Section 6 hereof, the Underwriters will pay all of their own costs and expenses, including the fees of Underwriters' Counsel and any advertising expenses in connection with any offers the Underwriters may make.

(k) LISTING. The Company will use its best efforts to effect the listing of the Securities on the NYSE.

(l) USE OF PROCEEDS. The Company will use the net proceeds from the issuance and sale of the Securities in the manner described in the Prospectus under "Use of Proceeds".

5. CONDITIONS TO UNDERWRITER'S OBLIGATIONS. The obligations of the several Underwriters under this Agreement shall be subject to the condition that all representations and warranties of the Company contained in this Agreement are, at and as of the Closing Date, true

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and correct, the condition that the Company shall have performed all of its obligations hereunder on or prior to the Closing Date and the following additional conditions:

(a) FILING OF PROSPECTUS WITH SEC; NO STOP ORDER; 1935 ACT ORDER IN FULL FORCE AND EFFECT. The Prospectus, and any supplements thereto, shall have been filed with the SEC within the time period prescribed for such filing by Rule 424(b) under the 1933 Act and in accordance with Section 4(a) hereof; all requests for additional information on the part of the SEC shall have been complied with to the reasonable satisfaction of the Underwriters; no stop order suspending the effectiveness of the Registration Statement or any part thereof shall have been issued and no proceeding for that purpose shall have been initiated or threatened by the SEC; and the 1935 Act Order shall be in full force and effect and sufficient to authorize the transactions contemplated by this Agreement.

(b) OPINION OF UNDERWRITERS' COUNSEL. At the Closing Date, Underwriters' Counsel shall have furnished to you an opinion, dated the Closing Date, with respect to the validity of the Securities, the Prospectus and the Registration Statement and such other related matters as you may reasonably request, and Underwriters' Counsel shall have received such documents and information as it may reasonably request to enable it to pass upon such matters. In rendering such opinion, such counsel (A) may rely as to matters involving the application of the laws of the State of Missouri upon the opinion of Steven R. Sullivan, Vice President, General Counsel and Secretary of the Company, rendered pursuant to Section 5(c) hereof and (B) may rely as to matters of fact, to the extent deemed proper, on certificates of responsible officers of the Company and public officials.

(c) OPINION OF COMPANY COUNSEL. At the Closing Date, Steven R. Sullivan, Vice President, General Counsel and Secretary of the Company, shall have furnished to you an opinion, dated the Closing Date, in form and substance satisfactory to you, to the effect that:

(i) the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Missouri, with power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a Material Adverse Effect;

(ii) each subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation, with all power and authority (corporate and other) to own its properties and conduct its business as described in the Prospectus; each such subsidiary is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except to the extent that the failure to be so qualified or to be in good standing would not reasonably be expected to have a Material Adverse Effect; and all of the issued and outstanding common stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable, and all of such common stock (except with regard to 40% of the common stock of Electric Energy, Inc.) is owned by the Company, directly or indirectly, free from liens, encumbrances and defects of title;

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(iii) other than as described in the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or such subsidiaries is the subject which, if determined adversely to the Company or such subsidiaries, would individually or in the aggregate reasonably be expected to have a Material Adverse Effect; to the best of such counsel's knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others; and the statements included or incorporated by reference in the Prospectus describing any legal proceedings or material contracts or agreements relating to the Company or any of its subsidiaries fairly summarize such matters;

(iv) this Agreement has been duly authorized, executed and delivered by the Company;

(v) the Securities have been duly authorized by the Company for issuance and sale to the Underwriters pursuant to this Agreement and, when issued and delivered by the Company pursuant to this Agreement against payment of the consideration set forth herein, will be validly issued, fully paid and non-assessable; the Common Stock conforms in all material respects to all statements relating thereto contained in the Prospectus and such description conforming to the rights set forth in the instruments defining the same; no holder of the Securities will be subject to personal liability solely by reason of being such a holder; and the issuance of the Securities is not subject to the preemptive or other similar rights of any securityholder of the Company or any of its subsidiaries;

(vi) the form of certificate used to evidence the Common Stock complies in all material respects with all applicable statutory requirements, with any applicable requirements of the articles of incorporation and by-laws of the Company and the requirements of the NYSE;

(vii) the issue and sale of the Securities by the Company, and the compliance by the Company with all of the provisions of this Agreement, and the consummation of the transactions herein contemplated, will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, nor will such action result in any violation of the provisions of the articles of incorporation or by-laws of the Company or any statute or any order, rule or regulation known to such counsel of any court or governmental agency or body having jurisdiction over the Company or any of its properties; and the execution, delivery and performance of this Agreement will not require the approval or consent of any holder or trustee of any debt or other obligations or securities of the Company which will not have been obtained;

(viii) the Company is not, and, after giving effect to the offering and sale of the Securities, the Company will not be, an "investment company," or an entity "controlled" by an investment company, as such terms are defined in the Investment Company Act of 1940, as amended;

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(ix) the SEC has issued the 1935 Act Order authorizing the issuance and sale of the Securities by the Company; the 1935 Act Order is in full force and effect and is sufficient to authorize the transactions contemplated by this Agreement; and no other consent, approval, authorization, order, registration, filing or qualification of or with any court or governmental agency or body is required for the issue and sale of the Securities by the Company, or the consummation by the Company of the transactions contemplated by this Agreement, except such as have been obtained under the 1933 Act and the 1939 Act and such consents, approvals, authorizations, orders, registrations, filings or qualifications as may be required under state securities or blue sky laws in connection with the purchase and distribution of the Securities by the Underwriters; and

(x) the Registration Statement, at the Effective Date, and the Prospectus, at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act (except in each case as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass), complied as to form in all material respects with the requirements of the 1933 Act and the 1939 Act and the respective rules and regulations of the SEC thereunder; each Incorporated Document as originally filed pursuant to the 1934 Act (except as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass) complied as to form when so filed in all material respects with the requirements of the 1934 Act and the rules and regulations of the SEC thereunder; the Registration Statement has become, and on the Closing Date is, effective under the 1933 Act and, to the best of such counsel's knowledge, no proceedings for a stop order with respect thereto are threatened or pending under Section 8 of the 1933 Act; and nothing has come to the attention of such counsel that has caused it to believe that the Registration Statement (except as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass), at the Effective Date, 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 (except as to financial statements and other financial data contained or incorporated by reference therein, upon which such counsel need not pass), at the time it was filed with the SEC pursuant to Rule 424(b) under the 1933 Act or on the Closing Date, included or includes any 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.

Such opinion shall also state that such counsel has no knowledge of any litigation, pending or threatened, that challenges the validity of the Securities or this Agreement, or that seeks to enjoin the performance of the Company's obligations hereunder or thereunder or that might reasonably be expected to have a Material Adverse Effect except as described in the Prospectus.

In rendering such opinion, such counsel may rely as to matters of fact, to the extent deemed proper, on certificates of responsible officers of the Company and public officials. Such counsel's opinion may further state that it is addressed to the Underwriters and is rendered solely for their benefit and may not be relied upon in any manner by any other person (other than Underwriters' Counsel as to certain matters involving the application of the laws of the State of Missouri in its opinion to the Underwriters on the date of such opinion) without such counsel's prior written consent.

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(d) LETTERS OF ACCOUNTANTS. On the date of this Agreement, and at the Closing Date, the Accountants shall have furnished to the Underwriters letters, dated the date of this Agreement and the Closing Date, respectively, in form and substance satisfactory to the Underwriters, confirming that they are independent accountants within the meaning of the 1933 Act and the rules and regulations of the SEC thereunder with respect to the Company and its subsidiaries and stating in effect that:

(i) in the opinion of the Accountants, the consolidated financial statements and schedules included or incorporated by reference in the Prospectus and audited by them comply as to form in all material respects with the applicable accounting requirements of the 1933 Act and the 1934 Act and the respective rules and regulations of the SEC thereunder; and

(ii) on the basis of a reading of the unaudited consolidated financial statements included or incorporated by reference in the Prospectus and the latest available interim unaudited consolidated financial statements of the Company, the performance of the procedures specified by the American Institute of Certified Public Accountants for a review of any such financial statements as described in Statement on Auditing Standards No. 71, inquiries of officials of the Company responsible for financial and accounting matters and a reading of the minutes of meetings of the stockholders and the Board of Directors of the Company and the Audit Committee thereof through a specified date not more than five days prior to the date of the applicable letter, nothing came to the attention of the Accountants that caused them to believe that: (A) any material modification should be made to the unaudited consolidated financial statements included or incorporated by reference in the Prospectus for them to be in conformity with generally accepted accounting principles or any such financial statements do not comply as to form in all material respects with the applicable accounting requirements of the 1933 Act or the 1934 Act and the respective rules and regulations of the SEC thereunder; (B) for the period from the date of the latest consolidated financial statements included or incorporated by reference in the Prospectus through the date of the most recent available consolidated financial statements of the Company and at a subsequent date not more than five days prior to the date of such letter, there were any decreases in total consolidated net sales, income from operations or net income as compared with the comparable period of the preceding year; or (C) at the date of the most recent available financial statements of the Company and at a subsequent date not more than five days prior to the date of such letter, there was any change in the capital stock of the Company, any increase in long-term debt of the Company, any decrease in consolidated net current assets (working capital) of the Company or any decrease in common shareholders' equity of the Company as compared with the amounts shown in the most recent consolidated balance sheet included or incorporated by reference in the Prospectus, except in all instances for changes, increases or decreases that the Prospectus discloses have occurred or may occur, or for changes, increases or decreases that are described in such letter that are reasonably satisfactory to you.

Such letter shall also cover such other matters as you shall reasonably request, including but not limited to the Company's "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained in the Company's financial statements included or incorporated by reference in the Prospectus and any other information of an accounting or financial nature included or incorporated by reference therein that is derived from the accounting records of the Company.

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(e) NO MATERIAL CHANGES. (i) Neither the Company nor any of its subsidiaries shall have sustained, since the date of the most recent audited consolidated financial statements included or incorporated by reference in the Prospectus, any loss or interference with their business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth in the Prospectus, and (ii) since the respective dates as of which information is given in the Prospectus, there shall not have been any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole, otherwise than as described in the Prospectus, the effect of which, in any such case described in clause (i) or
(ii), in the judgment of the Underwriters makes it impracticable or inadvisable to proceed with the public offering or the delivery of the Securities on the terms and in the manner contemplated in the Prospectus or to enforce contracts for the sale of any Securities.

(f) APPROVAL OF LISTING. At the Closing Date, the Securities shall have been approved for listing on the NYSE, subject only to official notice of issuance.

(g) LOCK-UP AGREEMENTS. At the date of this Agreement, the Underwriters shall have received an agreement substantially in the form of Exhibit A attached hereto signed by the persons listed on Schedule III attached hereto.

(h) NONOCCURRENCE OF CERTAIN EVENTS. On or after the date of this Agreement, there shall not have occurred any of the following: (i) a suspension or limitation of trading in securities of the Company or generally on the New York Stock Exchange, the American Stock Exchange or the Nasdaq Stock Market or any setting of minimum or maximum prices for trading thereon; (ii) a general moratorium on commercial banking activities in New York, New York declared by the relevant authorities or a material disruption in commercial banking or securities settlement or clearance services in the United States; (iii) the outbreak or escalation of hostilities involving the United States or the declaration by the United States of a national emergency or war; or (iv) the occurrence of any other calamity or crisis or any change in financial, political or economic conditions in the United States or elsewhere, which, in the case of either clause (iii) or (iv), in the judgment of the Underwriters, makes it impracticable or inadvisable to proceed with the public offering or the delivery of the Securities on the terms and in the manner contemplated in the Prospectus or to enforce contracts for the sale of any of the Securities.

(i) OFFICERS' CERTIFICATE. At the Closing Date, the Company shall have furnished or caused to be furnished to the Underwriters a certificate, dated the Closing Date, of (i) the chief executive officer, the President or any Senior Vice President of the Company and (ii) the Treasurer of the Company in which such officers shall state that the representations and warranties of the Company in this Agreement are true and correct in all material respects at and as of the Closing Date, and that the Company has complied with all agreements and has satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date and that, subsequent to the respective dates as of which information is given in the Prospectus, there has been no material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders' equity or consolidated results of operations of the Company and its subsidiaries, taken as a whole, otherwise than as described in the Prospectus.

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(j) CONDITIONS TO PURCHASE OF OPTION SECURITIES. In the event that the Underwriters exercise their option provided in Section 1(b) hereof to purchase all or any portion of the Option Securities, the representations and warranties of the Company contained herein and the statements in any certificates furnished by the Company or any subsidiary hereunder shall be true and correct as of each Date of Delivery and, at such Date of Delivery, the Underwriters shall have received:

(i) OFFICERS' CERTIFICATE. A certificate, dated such Date of Delivery, of (x) the chief executive officer, the President or any Senior Vice President of the Company and (y) the Treasurer of the Company confirming that the certificate delivered at the Closing Date pursuant to
Section 5(i) hereof remains true and correct as of such Date of Delivery.

(ii) OPINION OF COMPANY COUNSEL. The favorable opinion of Steven R. Sullivan, Vice President, General Counsel and Secretary of the Company, in form and substance satisfactory to Underwriters' Counsel, dated such Date of Delivery, relating to the Option Securities to be purchased on such Date of Delivery and otherwise to the same effect as the opinion required by Section 5(c) hereof.

(iii) OPINION OF UNDERWRITERS' COUNSEL. The favorable opinion of Underwriters' Counsel, dated such Date of Delivery, relating to the Option Securities to be purchased on such Date of Delivery and otherwise to the same effect as the opinion required by Section 5(b) hereof.

(iv) BRING-DOWN LETTER OF ACCOUNTANTS. A letter from the Accountants, in form and substance satisfactory to the Underwriters and dated such Date of Delivery, substantially in the same form and substance as the letter furnished to the Underwriters pursuant to Section 5(d) hereof, except that the "specified date" in the letter furnished pursuant to this paragraph shall be a date not more than five business days prior to such Date of Delivery.

(k) OTHER DOCUMENTS AND CERTIFICATES. At the Closing Date and each Date of Delivery, if any, Underwriters' Counsel shall have been furnished with all such documents, certificates and opinions as Underwriters' Counsel may reasonably request and that are customary for transactions of a similar nature, and of which the Company has been notified in writing prior to the date hereof, in order to evidence the accuracy and completeness of any of the representations, warranties, certificates or other written statements of the Company provided to the Underwriters pursuant to this Agreement, the performance of any of the covenants of the Company, or the fulfillment of any of the conditions herein contained. All proceedings taken by the Company at or prior to the Closing Date or any Date of Delivery in connection with the authorization, issuance and sale of the Securities as contemplated by this Agreement, including, without limitation, the execution of this Agreement, shall be reasonably satisfactory in form and substance to the Underwriters and Underwriters' Counsel.

In case any of the conditions specified above in this Section 5 shall not have been fulfilled, this Agreement may be terminated by you upon mailing or otherwise delivering written notice thereof to the Company. Any such termination shall be without liability of either party to the other party except as otherwise provided in Section 4(j) hereof and except for any liability under
Section 6 hereof.

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6. INDEMNIFICATION AND CONTRIBUTION

(a) INDEMNIFICATION BY COMPANY. The Company will indemnify and hold harmless each Underwriter against any losses, claims, damages, liabilities or expenses, as and when incurred, to which such Underwriter may become subject, joint or several, under the 1933 Act or otherwise, insofar as such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof), arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities, or any amendment or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and will promptly reimburse such Underwriter for any reasonable expenses (including reasonable fees and expenses for no more than one law firm for the Underwriters) when and as incurred by such Underwriter in connection with investigating or defending any such action or claim; PROVIDED, HOWEVER, that the Company shall not be liable in any such case to an Underwriter to the extent that any such loss, claim, damage, liability or expense arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities or any such amendment or supplement thereto in reliance upon and in conformity with the Underwriter Information.

(b) INDEMNIFICATION BY THE UNDERWRITERS. Each Underwriter, severally, will indemnify and hold harmless the Company against any losses, claims, damages, liabilities or expenses to which the Company may become subject, under the 1933 Act or otherwise, insofar as such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities or any amendment or supplement thereto, or arise out of are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in any Preliminary Prospectus, the Registration Statement, the Prospectus or any other prospectus relating to the Securities or any such amendment or supplement, in reliance upon and in conformity with the Underwriter Information, and will reimburse the Company for any reasonable expenses (including reasonable fees and expenses for no more than one law firm for the Company) when and as incurred by the Company in connection with investigating or defending any such action or claim.

(c) GENERAL. Promptly after receipt by an indemnified party under
Section 6(a) or 6(b) hereof of notice of the commencement of any action, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under Section 6(a) or 6(b) hereof, notify such indemnifying party in writing of the commencement thereof, but the omission so to notify such indemnifying party shall not relieve such indemnifying party from any liability except to the extent that it has been prejudiced in any material respect by such failure or from any liability that it may have to any such indemnified party otherwise than under Section 6(a) or 6(b) hereof. In case any such action shall be brought against any such indemnified party and it shall notify such indemnifying party of the commencement thereof, such indemnifying party shall be entitled to participate therein and, to the extent that it shall wish, jointly with any other indemnifying party under Section 6(a) or (b) hereof similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party (who shall not, except with the consent of such indemnified party, be counsel to such indemnifying party), and, after notice

16

from such indemnifying party to such indemnified party of its election so to assume the defense thereof, such indemnifying party shall not be liable to such indemnified party under Section 6(a) or 6(b) hereof for any legal expenses of other counsel or any other expenses, in each case subsequently incurred by such indemnified party, in connection with the defense thereof other than reasonable costs of investigation. Notwithstanding the foregoing, the indemnified party shall have the right to employ separate counsel at the indemnifying party's expense and to control its defense of such action if (i) the indemnifying party and the indemnified party agree to the retention of that counsel, (ii) the indemnifying party does not assume the defense of such action in a timely manner or (iii) the indemnified party reasonably objects to such assumption on the ground that there may be legal defenses available to it that are different from or in addition to those available to the indemnifying party or another indemnified party. No indemnifying party shall, without the written consent of the indemnified party, effect the settlement or compromise of, or consent to the entry of any judgment with respect to, any pending or threatened action or claim in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified party is an actual or potential party to such action or claim) unless such settlement, compromise or judgment (x) includes an unconditional release of the indemnified party from all liability arising out of such action or claim and (y) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of any indemnified party.

(d) CONTRIBUTION. If the indemnification provided for in this
Section 6 is unavailable to or insufficient to hold harmless an indemnified party under Section 6(a) or 6(b) hereof in respect of any losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) referred to therein, then each indemnifying party under Section 6(a) or 6(b) hereof shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other hand from the offering of the Securities. If, however, the allocation provided by the immediately preceding sentence is not permitted by applicable law, then each such indemnifying party shall contribute to such amount paid or payable by such indemnified party in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company on the one hand and the Underwriters on the other hand in connection with the statements or omissions that resulted in such losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof), 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 shall be deemed to be in the same proportion as the total net proceeds from such offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions the Underwriters received. 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 the Underwriters and the parties' relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 6(d) were determined by PRO RATA allocation or by any other method of allocation that does not take account of the equitable considerations referred to above in this
Section 6(d). The amount paid or payable by such an indemnified party as a result of the losses, claims, damages, liabilities or expenses (or actions or claims in respect thereof) referred to above in this Section 6(d) shall be deemed to include any legal or other expenses incurred by such indemnified party in connection with investigating or defending any such action or claim. The obligations of the Underwriters to contribute hereunder are several and not joint.

17

Notwithstanding the provisions of this Section 6(d), no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Securities underwritten by such Underwriter 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 1933 Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

(e) SCOPE OF OBLIGATIONS. The obligations of the Company under this
Section 6 shall be in addition to any liability that the Company may otherwise have and shall extend, upon the same terms and conditions, to each officer, director, employee, agent or other representative and to each person, if any, who controls each Underwriter within the meaning of the 1933 Act or the 1934 Act; and the obligations of the Underwriters under this Section 6 shall be in addition to any liability that the Underwriters may otherwise have and shall extend, upon the same terms and conditions, to each officer, director, employee, agent or other representative and to each person, if any, who controls the Company within the meaning of the 1933 Act or the 1934 Act.

7. REPRESENTATIONS, WARRANTIES AND AGREEMENTS TO SURVIVE DELIVERY. The respective indemnities, agreements, representations, warranties and other statements of the Company and the Underwriters, as set forth in this Agreement or made by or on behalf of the Company or the Underwriters, respectively, pursuant to this Agreement, shall remain in full force and effect, regardless of any investigation (or any statement as to the results thereof) made by or on behalf of the Underwriters, any of their officers, directors, employees, agents or other representatives or controlling persons, or the Company, any officer or director of the Company who signed the Registration Statement or any controlling person of the Company, and shall survive delivery of and payment for the Securities.

8. 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 ___________________ at the address set forth on the first page of this Agreement, attention of _______________; and notices to the Company shall be directed to Ameren Corporation, 1901 Chouteau Avenue, St. Louis, Missouri 63103, attention of Treasurer.

9. DEFAULT BY AN UNDERWRITER. If any Underwriter shall fail at the Closing Date to purchase the Securities which it is obligated to purchase under this Agreement (the DEFAULTED SECURITIES), the non-defaulting Underwriter or Underwriters shall have the right, but not the obligation, within 24 hours thereafter, to purchase, or to make arrangements for the appointment of another purchaser to purchase, the Defaulted Securities in such amounts as may be agreed upon and upon the terms herein set forth. If, however, the non-defaulting Underwriter or Underwriters shall not have completed such arrangements within such 24-hour period, then this Agreement shall terminate without liability on the part of the non-defaulting Underwriter or Underwriters. No action taken pursuant hereto shall relieve any defaulting Underwriter from liability in respect of its default. In the event of any such default which does not result in a termination of this Agreement, either the non-defaulting Underwriter or Underwriters or the Company shall have the right to postpone the Closing Date for a period not exceeding 7 days in order to effect any required changes in the Registration Statement, the Prospectus or in any other documents or arrangements related thereto. The term "Underwriter" for purposes of this Agreement includes any such person substituted for the defaulting Underwriter.

18

Notwithstanding any termination pursuant to this Section 9, the provisions of Sections 4(j), 6, 7 and 10 hereof shall remain in effect.

10. MISCELLANEOUS. The rights and duties of the parties to this Agreement shall, pursuant to New York General Obligations Law Section 5-1401, be governed by the law of the State of New York. This Agreement shall be binding upon, and inure solely to the benefit of, the Company and the Underwriters except to the extent provided in Section 6(e) hereof, and their respective heirs, executors, administrators, successors and assigns, and no other person shall acquire or have any right under or by virtue of this Agreement. No person who purchases any of the Securities from the Underwriters shall be deemed a successor or assign by reason merely of such purchase. This Agreement may be executed by any one or more of the parties hereto in any number of counterparts, each of which shall be deemed to be an original, but all such respective counterparts shall together constitute one and the same instrument. The word "or" shall not be exclusive, and all references in this Agreement to the words "herein," "hereof," "hereunder" and other words of similar import refer to this Agreement as a whole and not to any particular Section or subdivision hereof, and the captions to such Sections and subdivisions are for convenience only and shall not affect the construction hereof.

19

If the foregoing is in accordance with your understanding, please sign and return to the Company the enclosed duplicate hereof, whereupon this Agreement will become a binding agreement between the Company and the Underwriters in accordance with its terms.

Very truly yours,

AMEREN CORPORATION

By:

Name:


Title:

Accepted as of the date hereof:

[Names of Underwriters]

BY: [LEAD UNDERWRITER]

By:
Name:
Title:

20

SCHEDULE I

                                                NUMBER OF
                                                 INITIAL
NAME OF UNDERWRITER                             SECURITIES
--------------------------------------------- --------------





                                                 _______

     TOTAL..................................
                                                 =======


SCHEDULE II

1. The initial public offering price per share for the Securities shall be $_____.

2. The purchase price per share for the Securities to be paid by the several Underwriters shall be $____, being an amount equal to the initial public offering price set forth above less $____ per share; provided that the purchase price per share for any Option Securities purchased upon the exercise of the overallotment option described in Section 1(b) shall be reduced by an amount per share equal to any dividends or distributions declared by the Company and payable on the Initial Securities but not payable on the Option Securities.

Sch II-1


SCHEDULE III

List of persons subject to lock-up


Exhibit A

__________, 200_

[Names of Underwriters]

c/o [Name and Address of
Lead Underwriter]

Re: PROPOSED PUBLIC OFFERING BY AMEREN CORPORATION

Dear Sirs:

The undersigned, a stockholder and an officer and/or director of Ameren Corporation, a Missouri corporation (the "Company"), understands that _________________ ("_________") proposes to enter into an Underwriting Agreement (the "Underwriting Agreement") with the Company providing for the public offering of shares (the "Securities") of the Company's common stock, $.01 par value per share (the "Common Stock"). In recognition of the benefit that such an offering will confer upon the undersigned as a stockholder and an officer and/or director of the Company, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned agrees with each underwriter named in the Underwriting Agreement that, during a period of 90 days from the date of the Underwriting Agreement, the undersigned will not, without the prior written consent of _______________, directly or indirectly, (i) 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 for the sale of, or otherwise dispose of or transfer any shares of Common Stock or any securities convertible into or exchangeable or exercisable for Common Stock, whether now owned or hereafter acquired by the undersigned or with respect to which the undersigned has or hereafter acquires the power of disposition, or file any registration statement under the Securities Act of 1933, as amended, with respect to any of the foregoing or (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the economic consequence of ownership of the Common Stock, whether any such swap or transaction is to be settled by delivery of Common Stock or other securities, in cash or otherwise.

Very truly yours,

Signature:

Print Name:

A-1

EXHIBIT 4.5


AMEREN CORPORATION

AND

THE BANK OF NEW YORK

TRUSTEE


INDENTURE

DATED AS OF DECEMBER 1, 2001



CROSS REFERENCE SHEET SHOWING THE LOCATION IN THE INDENTURE OF THE
PROVISIONS INSERTED CORRELATIVE TO SECTIONS 310 THROUGH 318(a),
INCLUSIVE, OF THE TRUST INDENTURE ACT OF 1939

Trust Indenture Act                                         Indenture
    Section                                                   Section

310(a) (1).......................................................9.09
   (a) (2).......................................................9.09
   (a) (3).............................................Not Applicable
   (a) (4).............................................Not Applicable
   (a) (5).......................................................9.09
   (b)...........................................................9.08
   (c).................................................Not Applicable
311(a)...........................................................9.14
   (b)...........................................................9.14
   (c).................................................Not Applicable
312(a)...............................................7.01 and 7.02(a)
   (b)........................................................7.02(b)
   (c)........................................................7.02(c)
313(a)........................................................7.04(a)
   (b)........................................................7.04(b)
   (c)........................................................7.04(d)
   (d)........................................................7.04(c)
314(a)..................................................7.03 and 6.06
   (b)...........................................................6.05
   (c) (1).............................................1.03 and 15.05
   (c) (2).............................................1.03 and 15.05
   (c) (3).............................................Not Applicable
   (d)..................................................1.03 and 4.06
   (e).......................................................15.05(b)
   (f).................................................Not Applicable
315(a)...........................................................9.01
   (b)...........................................................8.08
   (c)........................................................9.01(a)
   (d)........................................................9.01(b)
   (e)...........................................................8.09
316(a).................................................8.07 and 10.04
   (b)..............................................8.04(b) and 13.02
   (c)..........................................................10.06
317(a) (1)....................................................8.02(b)
   (a) (2)....................................................8.02(c)
   (b)..................................................5.02 and 6.04
318(a)..........................................................15.07
-------------------

NOTE: This reconciliation and tie shall not, for any purpose, be deemed to be a part of the Indenture.


TABLE OF CONTENTS

                                                                                                             PAGE
                                                    ARTICLE I

                                                   DEFINITIONS

Section 1.01      General........................................................................................1
Section 1.02      Trust Indenture Act............................................................................2
Section 1.03      Definitions....................................................................................2


                                                    ARTICLE II

                                     FORM, ISSUE, EXECUTION, REGISTRATION AND
                                                 EXCHANGE OF NOTES


Section 2.01      Forms Generally................................................................................6
Section 2.02      Form Of Trustee's Certificate Of Authentication................................................6
Section 2.03      Amount Unlimited...............................................................................6
Section 2.04      Denominations, Dates, Interest Payment And Record Dates........................................6
Section 2.05      Execution, Authentication, Delivery And Dating.................................................7
Section 2.06      Exchange And Registration Of Transfer Of Notes................................................10
Section 2.07      Mutilated, Destroyed, Lost Or Stolen Notes....................................................11
Section 2.08      Temporary Notes...............................................................................12
Section 2.09      Cancellation Of Notes Paid, Etc...............................................................12
Section 2.10      Interest Rights Preserved.....................................................................12
Section 2.11      Special Record Date...........................................................................12
Section 2.12      Payment Of Notes..............................................................................13
Section 2.13      Notes Issuable In The Form Of A Global Note...................................................14
Section 2.14      CUSIP and ISIN Numbers........................................................................16


                                                    ARTICLE III

                                                REDEMPTION OF NOTES


Section 3.01      Applicability Of Article......................................................................16
Section 3.02      Notice Of Redemption; Selection Of Notes......................................................16
Section 3.03      Payment Of Notes On Redemption; Deposit Of Redemption Price...................................17

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                                                    ARTICLE IV

                                                   SINKING FUNDS


Section 4.01      Applicability of Article......................................................................18
Section 4.02      Satisfaction of Sinking Fund Payments with Notes..............................................18
Section 4.03      Redemption of Notes for Sinking Fund..........................................................19


                                                     ARTICLE V

                                   SATISFACTION AND DISCHARGE; UNCLAIMED MONEYS


Section 5.01      Satisfaction and Discharge of Indenture.......................................................19
Section 5.02      Application of Trust Funds; Indemnification...................................................20
Section 5.03      Legal Defeasance..............................................................................20
Section 5.04      Covenant Defeasance...........................................................................22
Section 5.05      Repayment to Company..........................................................................23


                                                    ARTICLE VI

                                        PARTICULAR COVENANTS OF THE COMPANY


Section 6.01      Payment Of Principal And Interest.............................................................23
Section 6.02      Offices For Payments, Etc.....................................................................23
Section 6.03      Appointment To Fill A Vacancy In Office Of Trustee............................................24
Section 6.04      Provision As To Paying Agent..................................................................24
Section 6.05      Corporate Existence...........................................................................25
Section 6.06      Certificates And Notice To Trustee............................................................25


                                                    ARTICLE VII

                                          NOTEHOLDER LISTS AND REPORTS BY
                                            THE COMPANY AND THE TRUSTEE


Section 7.01      Company To Furnish Noteholder Lists...........................................................25
Section 7.02      Preservation and Disclosure of Noteholder Lists...............................................26
Section 7.03      Reports By The Company........................................................................27
Section 7.04      Reports By The Trustee........................................................................28

-ii-

                                                   ARTICLE VIII

                                      REMEDIES OF THE TRUSTEE AND NOTEHOLDERS
                                               ON EVENTS OF DEFAULT


Section 8.01      Events Of Default.............................................................................28
Section 8.02      Collection Of Indebtedness By Trustee; Trustee May Prove Debt.................................30
Section 8.03      Application Of Proceeds.......................................................................32
Section 8.04      Limitations On Suits By Noteholders...........................................................33
Section 8.05      Suits For Enforcement.........................................................................33
Section 8.06      Powers And Remedies Cumulative; Delay Or Omission Not Waiver Of Default.......................34
Section 8.07      Direction of Proceedings and Waiver of Defaults By Majority of Noteholders....................34
Section 8.08      Notice of Default.............................................................................35
Section 8.09      Undertaking To Pay Costs......................................................................35
Section 8.10      Restoration of Rights on Abandonment of Proceedings...........................................35
Section 8.11      Waiver of Usury, Stay or Extension Laws.......................................................35


                                                    ARTICLE IX

                                              CONCERNING THE TRUSTEE


Section 9.01      Duties and Responsibilities of Trustee........................................................36
Section 9.02      Reliance on Documents, Opinions, Etc..........................................................37
Section 9.03      No Responsibility For Recitals, Etc...........................................................38
Section 9.04      Trustee, Authenticating Agent, Paying Agent Or Registrar May Own Notes........................38
Section 9.05      Moneys To Be Held In Trust....................................................................38
Section 9.06      Compensation And Expenses Of Trustee..........................................................38
Section 9.07      Officers' Certificate As Evidence.............................................................39
Section 9.08      Conflicting Interest Of Trustee...............................................................39
Section 9.09      Existence And Eligibility Of Trustee..........................................................39
Section 9.10      Resignation Or Removal Of Trustee.............................................................39
Section 9.11      Appointment Of Successor Trustee..............................................................40
Section 9.12      Acceptance By Successor Trustee...............................................................41
Section 9.13      Succession By Merger, Etc.....................................................................41
Section 9.14      Limitations On Rights Of Trustee As A Creditor................................................42
Section 9.15      Authenticating Agent..........................................................................42


                                                     ARTICLE X

                                            CONCERNING THE NOTEHOLDERS


Section 10.01     Action By Noteholders.........................................................................42

-iii-

Section 10.02     Proof Of Execution By Noteholders.............................................................43
Section 10.03     Persons Deemed Absolute Owners................................................................43
Section 10.04     Company-Owned Notes Disregarded...............................................................43
Section 10.05     Revocation Of Consents; Future Holders Bound..................................................43
Section 10.06     Record Date For Noteholder Acts...............................................................44


                                                    ARTICLE XI

                                               NOTEHOLDERS' MEETING


Section 11.01     Purposes Of Meetings..........................................................................44
Section 11.02     Call Of Meetings By Trustee...................................................................45
Section 11.03     Call Of Meetings By Company Or Noteholders....................................................45
Section 11.04     Qualifications For Voting.....................................................................45
Section 11.05     Regulations...................................................................................45
Section 11.06     Voting........................................................................................46
Section 11.07     Rights Of Trustee Or Noteholders Not Delayed..................................................46


                                                    ARTICLE XII

                                CONSOLIDATION, MERGER, SALE, TRANSFER OR CONVEYANCE


Section 12.01     Company May Consolidate, Etc. Only On Certain Terms...........................................46
Section 12.02     Successor Corporation Substituted.............................................................47


                                                   ARTICLE XIII

                                              SUPPLEMENTAL INDENTURES


Section 13.01     Supplemental Indentures Without Consent Of Noteholders........................................47
Section 13.02     Supplemental Indentures With Consent Of Noteholders...........................................48
Section 13.03     Compliance With Trust Indenture Act; Effect Of Supplemental Indentures........................49
Section 13.04     Notation On Notes.............................................................................50
Section 13.05     Evidence Of Compliance Of Supplemental Indenture To Be Furnished Trustee......................50


                                                    ARTICLE XIV

                                            IMMUNITY OF INCORPORATORS,
                                       STOCKHOLDERS, OFFICERS AND DIRECTORS


Section 14.01     Indenture And Notes Solely Corporate Obligations..............................................50

-iv-

                                                    ARTICLE XV

                                             MISCELLANEOUS PROVISIONS


Section 15.01     Provisions Binding On Company's Successors....................................................50
Section 15.02     Official Acts By Successor Corporation........................................................50
Section 15.03     Notices.......................................................................................51
Section 15.04     Governing Law.................................................................................51
Section 15.05     Evidence Of Compliance With Conditions Precedent..............................................51
Section 15.06     Business Days.................................................................................52
Section 15.07     Trust Indenture Act To Control................................................................52
Section 15.08     Table Of Contents, Headings, Etc..............................................................52
Section 15.09     Execution In Counterparts.....................................................................52
Section 15.10     Manner Of Mailing Notice To Noteholders.......................................................52
Section 15.11     Approval By Trustee Of Counsel................................................................53

-v-

THIS INDENTURE, dated as of December 1, 2001, between AMEREN CORPORATION, a corporation duly organized and existing under the laws of the State of Missouri (the "COMPANY"), and THE BANK OF NEW YORK, a New York banking corporation, as trustee (the "TRUSTEE").

W I T N E S S E T H

WHEREAS, for its lawful corporate purposes, the Company has duly authorized the execution and delivery of this Indenture to provide for the issuance from time to time of its unsecured debentures, notes or other evidences of indebtedness (the "Notes"), to be issued in one or more series as in this Indenture provided; and

WHEREAS, all acts and things necessary to make this Indenture a valid agreement according to its terms have been done and performed, and the execution of this Indenture and the issue hereunder of the Notes have in all respects been duly authorized;

NOW THEREFORE, THIS INDENTURE WITNESSETH:

That in order to declare the terms and conditions upon which the Notes are, and are to be authenticated, issued and delivered, and in consideration of the premises, of the purchase and acceptance of the Notes by the Holders thereof and of the sum of one dollar duly paid to it by the Trustee at the execution of this Indenture, the receipt whereof is hereby acknowledged, the Company covenants and agrees with the Trustee for the equal and proportionate benefit of the respective Holders from time to time of the Notes or of any series thereof, as follows:

ARTICLE I

DEFINITIONS

Section 1.01 GENERAL.

(a) The terms defined in this Article I (whether or not capitalized and except as herein otherwise expressly provided or unless the context otherwise requires) for all purposes of this Indenture and of any indenture supplemental hereto or Company Order (as hereinafter defined) shall have the respective meanings specified in this Article I.

(b) All accounting terms used herein and not expressly defined herein shall have the meanings assigned to them in accordance with generally accepted accounting principles in the United States of America, and, except as otherwise herein expressly provided, the term "generally accepted accounting principles" with respect to any computation required or permitted hereunder shall mean such accounting principles as are generally accepted in the United States of America at the date of such computation; PROVIDED, that when two or more principles are so generally accepted, it shall mean that set of principles consistent with those in use by the Company.


Section 1.02 TRUST INDENTURE ACT.

(a) Whenever this Indenture refers to a provision of the Trust Indenture Act of 1939 (the "TIA"), such provision is incorporated by reference in and made a part of this Indenture.

(b) Unless otherwise indicated, all terms used in this Indenture that are defined by the TIA, defined by the TIA by reference to another statute or defined by a rule of the Commission under the TIA shall have the meanings assigned to them in the TIA or such statute or rule as in force on the date of execution of this Indenture.

(c) The Company and the Trustee agree to comply with the TIA notwithstanding any exemption that may be available thereunder.

Section 1.03 DEFINITIONS. For purposes of this Indenture, the following terms shall have the following meanings.

"AUTHENTICATING AGENT" shall mean any agent of the Trustee which shall be appointed and acting pursuant to Section 9.15 hereof.

"AUTHORIZED AGENT" shall mean any agent of the Company designated as such by an Officers' Certificate delivered to the Trustee.

"BOARD OF DIRECTORS" shall mean the Board of Directors of the Company or the Executive Committee of such Board or any other duly authorized committee of such Board.

"BOARD RESOLUTION" shall mean a copy of a resolution certified by the Secretary or an Assistant Secretary of the Company to have been duly adopted by the Board of Directors and to be in full force and effect on the date of such certification, and delivered to the Trustee.

"BUSINESS DAY" shall mean each Monday, Tuesday, Wednesday, Thursday and Friday that is not a day on which banking institutions or trust companies in the Borough of Manhattan, the City and State of New York, or in the city where the corporate trust office of the Trustee is located, are obligated or authorized by law or executive order to close, except as otherwise specified in a Company Order pursuant to Section 2.05 hereof.

"COMMISSION" shall mean the United States Securities and Exchange Commission, or if at any time hereafter the Commission is not existing or performing the duties now assigned to it under the TIA, then the body performing such duties.

"COMPANY" shall mean the corporation named as the "Company" in the first paragraph of this Indenture, and its successors and assigns permitted hereunder.

"COMPANY ORDER" shall mean a written order or certificate signed in the name of the Company by one of the Chairman, the President, any Vice President (whether or not designated by a number or numbers or a word or words added before or after the title "Vice President"), the Treasurer or an Assistant Treasurer of the Company, and delivered to the Trustee. At the

2

Company's option, a Company Order may take the form of a supplemental indenture to this Indenture.

"CORPORATE TRUST OFFICE OF THE TRUSTEE", or other similar term, shall mean the corporate trust office of the Trustee, at which at any particular time its corporate trust business shall be principally administered, which office is at the date of the execution of this Indenture located at 101 Barclay Street, Floor 21W, New York, New York 10286.

"DEBT" shall mean any outstanding funded obligations of the Company for money borrowed, whether or not evidenced by notes, debentures, bonds or other securities, reimbursement obligations under letters of credit, or guarantees of any such obligations issued by another Person.

"DEPOSITARY" shall mean, unless otherwise specified in a Company Order pursuant to Section 2.05 hereof, The Depository Trust Company, New York, New York ("DTC"), or any successor thereto registered and qualified as a clearing agency under the Securities Exchange Act of 1934, or other applicable statute or regulation.

"EVENT OF DEFAULT" shall mean any event specified in Section 8.01 hereof, continued for the period of time, if any, and after the giving of the notice, if any, therein designated.

"GLOBAL NOTE" shall mean a Note that, pursuant to Section 2.05 hereof, is delivered to the Depositary or pursuant to the instructions of the Depositary and that shall be registered in the name of the Depositary or its nominee.

"HOLDER", "HOLDER OF NOTES" or "NOTEHOLDER" shall mean any Person in whose name at the time a particular Note is registered on the books of the Trustee kept for that purpose in accordance with the terms hereof.

"INDENTURE" shall mean this instrument as originally executed or, if amended or supplemented as herein provided, as so amended or supplemented, and shall include the terms and provisions of a particular series of Notes established pursuant to Section 2.05 hereof.

"INTEREST PAYMENT DATE", when used with respect to any Note, shall mean
(a) each date designated as such for the payment of interest on such Note specified in a Company Order pursuant to Section 2.05 hereof (provided that the first Interest Payment Date for such Note, the Original Issue Date of which is after a Regular Record Date but prior to the respective Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date), (b) a date of Maturity of such Note and (c) only with respect to defaulted interest on such Note, the date established by the Trustee for the payment of such defaulted interest pursuant to Section 2.11 hereof.

"MATURITY," when used with respect to any Note, shall mean the date on which the principal of such Note becomes due and payable as therein or herein provided, whether at the Stated Maturity thereof or by declaration of acceleration, redemption or otherwise.

3

"NOTE" or "NOTES" has the meaning stated in the first recital of this Indenture and more particularly means any note or notes, as the case may be, authenticated and delivered under this Indenture, including any Global Note.

"OFFICERS' CERTIFICATE" when used with respect to the Company, shall mean a certificate signed by one of the Chairman, the President, any Vice President (whether or not designated by a number or numbers or a word or words added before or after the title "Vice President"), and by the Chief Financial Officer, Treasurer, any Assistant Treasurer, the Secretary or an Assistant Secretary of the Company; provided, that no individual shall be entitled to sign in more than one capacity.

"OPINION OF COUNSEL" shall mean an opinion in writing signed by legal counsel, who may be an employee of the Company, meeting the applicable requirements of Section 15.05 hereof. If the Indenture requires the delivery of an Opinion of Counsel to the Trustee, the text and substance of which has been previously delivered to the Trustee, the Company may satisfy such requirement by the delivery by the legal counsel that delivered such previous Opinion of Counsel of a letter to the Trustee to the effect that the Trustee may rely on such previous Opinion of Counsel as if such Opinion of Counsel was dated and delivered the date delivery of such Opinion of Counsel is required. Any Opinion of Counsel may contain reasonable conditions and qualifications satisfactory to the Trustee.

"ORIGINAL ISSUE DATE" shall mean for a Note, or portions thereof, the date upon which it, or such portion, was issued by the Company pursuant to this Indenture and authenticated by the Trustee (other than in connection with a transfer, exchange or substitution).

"OUTSTANDING", when used with reference to Notes, shall, subject to
Section 10.04 hereof, mean, as of any particular time, all Notes authenticated and delivered by the Trustee under this Indenture, except

(a) Notes theretofore cancelled by the Trustee or delivered to the Trustee for cancellation;

(b) Notes, or portions thereof, for the payment or redemption of which moneys in the necessary amount shall have been deposited in trust with the Trustee or with any paying agent (other than the Company), provided that if such Notes are to be redeemed prior to the Stated Maturity thereof, notice of such redemption shall have been given as provided in Article III, or provisions satisfactory to the Trustee shall have been made for giving such notice;

(c) Notes, or portions thereof, that have been paid and discharged or are deemed to have been paid and discharged pursuant to the provisions of this Indenture; and

(d) Notes in lieu of or in substitution for which other Notes shall have been authenticated and delivered, or which have been paid, pursuant to Section 2.07 hereof.

"PERIODIC OFFERING" means an offering of Notes of a series from time to time the specific terms of which Notes, including without limitation the rate or rates of interest, if any, thereon, the Stated Maturity or Maturities thereof and the redemption provisions, if any, with

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respect thereto, are to be determined by the Company or its agents upon the issuance of such Notes.

"PERSON" shall mean any individual, corporation, company partnership, joint venture, limited liability company, association, joint-stock company, trust, unincorporated organization or government or any agent or political subdivision thereof.

"PRINCIPAL EXECUTIVE OFFICES OF THE COMPANY" shall mean 1901 Chouteau Avenue, St. Louis, Missouri 63103, or such other place where the main corporate offices of the Company are located as designated in writing to the Trustee by an Authorized Agent.

"REGULAR RECORD DATE" shall mean, unless otherwise specified in a Company Order pursuant to Section 2.05 hereof, for an Interest Payment Date for a particular Note (except for an Interest Payment Date with respect to defaulted interest on such Note) (a) the fifteenth day next preceding each Interest Payment Date (unless the Interest Payment Date is the date of Maturity of such Note, in which event, the Regular Record Date shall be as described in clause
(b) hereof) and (b) the date of Maturity of such Note.

"RESPONSIBLE OFFICER" or "RESPONSIBLE OFFICERS" when used with respect to the Trustee shall mean one or more of the following: any assistant vice president, any assistant treasurer, any trust officer, any assistant trust officer, or any other officer or assistant officer of the Trustee customarily performing functions similar to those performed by the persons who at the time shall be such officers, respectively, or to whom any corporate trust matter is referred because of his or her knowledge of and familiarity with the particular subject.

"SPECIAL RECORD DATE" shall mean, with respect to any Note, the date established by the Trustee in connection with the payment of defaulted interest on such Note pursuant to Section 2.11 hereof.

"STATED MATURITY" shall mean with respect to any Note, the last date on which principal on such Note becomes due and payable as therein or herein provided, other than by declaration of acceleration or by redemption.

"SUBSIDIARY" shall mean, as to any Person, any corporation or other entity of which at least a majority of the securities or other ownership interest having ordinary voting power (absolutely or contingently) for the election of directors or other Persons performing similar functions are at the time owned directly or indirectly by such Person.

"TRUSTEE" shall mean The Bank of New York and, subject to Article IX, shall also include any successor Trustee.

"U.S. GOVERNMENT OBLIGATIONS" shall mean (i) direct non-callable obligations of, or non-callable obligations guaranteed as to timely payment of principal and interest by, the United States of America or obligations of a person controlled or supervised by and acting as an agency or instrumentality thereof for the payment of which obligations or guarantee the full faith and credit of the United States is pledged or (ii) certificates or receipts representing direct ownership interests in obligations or specified portions (such as principal or interest) of

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obligations described in clause (i) above, which obligations are held by a custodian in safekeeping in a manner satisfactory to the Trustee.

ARTICLE II

FORM, ISSUE, EXECUTION, REGISTRATION AND
EXCHANGE OF NOTES

Section 2.01 FORMS GENERALLY.

(a) The Notes shall be in such form as shall be established by a Company Order pursuant to Section 2.05(c) hereof with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by this Indenture, and may have such letters, numbers or other marks of identification and such legends or endorsements placed thereon as may be required to comply with applicable rules of any securities exchange or of the Depositary or with applicable law or as may, consistently herewith, be determined by the officers executing such Notes, as evidenced by their execution of such Notes.

(b) The definitive Notes shall be typed, printed, lithographed or engraved on steel engraved borders or may be produced in any other manner, all as determined by the officers executing such Notes, as evidenced by their execution of such Notes.

Section 2.02 FORM OF TRUSTEE'S CERTIFICATE OF AUTHENTICATION. The Trustee's certificate of authentication on all Notes shall be in substantially the following form:

Trustee's Certificate of Authentication

This Note is one of the Notes of the series herein designated, described or provided for in the within-mentioned Indenture.

The Bank of New York, as Trustee

By:
Authorized Signatory

Section 2.03 AMOUNT UNLIMITED. The aggregate principal amount of Notes that may be authenticated and delivered under this Indenture is unlimited, subject to compliance with the provisions of this Indenture.

Section 2.04 DENOMINATIONS, DATES, INTEREST PAYMENT AND RECORD DATES.

(a) The Notes of each series shall be issuable in registered form without coupons in denominations of $1,000 and integral multiples thereof or such other amount or amounts as may be authorized by the Board of Directors or a Company Order pursuant to a Board Resolution or in one or more indentures supplemental hereto; provided, that the principal amount of a Global Note shall not exceed $500,000,000 unless otherwise permitted by the Depositary.

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(b) Each Note shall be dated and issued as of the date of its authentication by the Trustee, and shall bear an Original Issue Date; each Note issued upon transfer, exchange or substitution of a Note shall bear the Original Issue Date or Dates of such transferred, exchanged or substituted Note, subject to the provisions of Section 2.13(d) hereof.

(c) Each Note shall accrue interest from the later of (1) its Original Issue Date or the date specified in such Note and (2) the most recent date to which interest has been paid or duly provided for with respect to such Note until the principal of such Note is paid or made available for payment, and interest on each Note shall be payable on each Interest Payment Date after the Original Issue Date.

(d) Each Note shall mature on a Stated Maturity specified in the Note. The principal amount of each outstanding Note shall be payable on the Stated Maturity date specified therein.

(e) Unless otherwise specified in a Company Order pursuant to
Section 2.05 hereof, interest on each of the Notes shall be calculated on the basis of a 360-day year of twelve 30-day months (and for any partial periods shall be calculated on the basis of the number of days elapsed in a 360-day year of twelve 30-day months) and shall be computed at a fixed rate until the Stated Maturity of such Notes. The method of computing interest on any Notes not bearing a fixed rate of interest shall be set forth in a Company Order pursuant to Section 2.05 hereof. Unless otherwise specified in a Company Order pursuant to Section 2.05 hereof, principal, interest and premium on the Notes shall be payable in the currency of the United States.

(f) Except as provided in the following sentence, the Person in whose name any Note is registered at the close of business on any Regular Record Date or Special Record Date with respect to an Interest Payment Date for such Note shall be entitled to receive the interest payable on such Interest Payment Date notwithstanding the cancellation of such Note upon any registration of transfer, exchange or substitution of such Note subsequent to such Regular Record Date or Special Record Date and prior to such Interest Payment Date. Any interest payable at Maturity shall be paid to the Person to whom the principal of such Note is payable.

(g) So long as the Trustee is the registrar and paying agent, the Trustee shall, as soon as practicable but no later than the Regular Record Date preceding each applicable Interest Payment Date, provide to the Company a list of the principal, interest and premium to be paid on Notes on such Interest Payment Date. The Trustee shall assume responsibility for withholding taxes on interest paid as required by law except with respect to any Global Note.

Section 2.05 EXECUTION, AUTHENTICATION, DELIVERY AND DATING.

(a) The Notes shall be executed on behalf of the Company by one of its Chairman, President, any Vice President (whether or not designated by a number or numbers or a word or words added before or after the title "Vice President"), its Treasurer or an Assistant Treasurer of the Company and attested by the Secretary or an Assistant Secretary of the Company. The signature of any of these officers on the Notes may be manual or facsimile. Typographical and other minor errors or defects in any such signature shall not affect the validity or enforceability of any Note that has been duly authenticated and delivered by the Trustee.

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(b) Notes bearing the manual or facsimile signatures of individuals who were at the time of execution the proper officers of the Company shall bind the Company, notwithstanding that such individuals or any of them have ceased to hold such offices prior to the authentication and delivery of such Notes or did not hold such offices at the date of such Notes.

(c) At any time and from time to time after the execution and delivery of this Indenture, the Company may deliver Notes of any series executed by the Company to the Trustee for authentication, together with or preceded by one or more Company Orders for the authentication and delivery of such Notes, and the Trustee in accordance with any such Company Order shall authenticate and make available for delivery such Notes; provided, however, that, with respect to Notes of a series subject to a Periodic Offering, (A) such Company Order may be delivered by the Company to the Trustee prior to the delivery to the Trustee of such Notes for authentication and delivery, (B) the Trustee shall authenticate and deliver Notes of such series for original issue from time to time, in an aggregate principal amount not exceeding the aggregate principal amount established for such series, all pursuant to a further Company Order or pursuant to such procedures acceptable to the Trustee as may be specified from time to time by such further Company Order, (C) the Stated Maturity or Maturities, Original Issue Date or Dates, interest rate or rates and any other terms of Notes of such series shall be determined by such further Company Order or pursuant to such procedures and (D) if provided for in such procedures, such Company Order may authorize authentication and delivery pursuant to oral or electronic instructions from the Company or its duly authorized agent or agents, which oral instructions shall be promptly confirmed in writing. Such Company Order shall specify the following with respect to each series of Notes: (i) the title of the Notes of such series (which shall distinguish the Notes of such series from Notes of all other series) and any limitations on the aggregate principal amount of the Notes to be issued as part of such series, (ii) the Original Issue Date for such series, (iii) the Stated Maturity of Notes of such series, (iv) the interest rate or rates, or method of calculation of such rate or rates, for such series and the date from which such interest will accrue, (v) the terms, if any, regarding the optional or mandatory redemption of such series, including redemption date or dates of such series, if any, and the price or prices applicable to such redemption, (vi) whether or not the Notes of such series shall be issued in whole or in part in the form of a Global Note and, if so, the Depositary for such Global Note if not DTC, (vii) the form of the Notes of such series, (viii) the maximum annual interest rate, if any, of the Notes permitted for such series, (ix) the period or periods within which, the price or prices at which and the terms and conditions upon which such series may be repaid, in whole or in part, at the option of the Holder thereof, (x) the establishment of any office or agency pursuant to Section 6.02 hereof, (xi) any Events of Default, in addition to those specified in Section 8.01 hereof, with respect to the Notes of such series, and any covenants of the Company for the benefit of the Holders of the Notes of such series in addition to those set forth in Articles VI and XII hereof, (xii) the terms, if any, pursuant to which the Notes of such series may be converted into or exchanged for shares of capital stock or other securities of the Company, and (xiii) any other terms of such series not inconsistent with this Indenture. With respect to Notes of a series subject to a Periodic Offering, such Company Order may provide general terms or parameters for Notes of such series and provide either that the specific terms of particular Notes of such series shall be specified in a further Company Order or that such terms shall be determined by the Company or its agents in accordance with such further Company Order as contemplated by the proviso of the first sentence of this Section 2.05(c). Prior to authenticating Notes of any series, and in accepting the additional responsibilities under this Indenture in

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relation to such Notes, the Trustee shall receive from the Company the following at or before the issuance of such series of Notes, and (subject to Section 9.01 hereof) shall be fully protected in relying upon, unless and until such documents have been superseded or revoked prior to such issuance:

(1) A Board Resolution authorizing such Company Order or Orders and, if the form of Notes is established by a Board Resolution or a Company Order pursuant to a Board Resolution, a copy of such Board Resolution;

(2) At the option of the Company, either an Opinion of Counsel or a letter addressed to the Trustee permitting it to rely on an Opinion of Counsel, stating substantially the following subject to customary qualifications and exceptions:

(A) if the form of such Notes has been established by or pursuant to a Board Resolution, a Company Order pursuant to a Board Resolution, or in a supplemental indenture as permitted by Section 2.01 hereof, that such form has been established in conformity with this Indenture;

(B) that this Indenture has been duly authorized, executed and delivered by the Company and constitutes a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms, except as may be limited by bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium and other similar laws relating to or affecting creditors' rights generally, general equitable principles (whether considered in a proceeding at law or in equity) and by an implied covenant of reasonableness, good faith and fair dealing;

(C) that this Indenture is qualified to the extent necessary under the TIA or, if not so required, that this Indenture is not required to be qualified under the TIA;

(D) that such Notes have been duly authorized and executed by the Company, and when authenticated by the Trustee and issued by the Company in the manner and subject to any conditions specified in such Opinion of Counsel, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms, except as may be limited by bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium and other similar laws relating to or affecting creditors' rights generally, general equitable principles (whether considered in a proceeding at law or in equity) and by an implied covenant of reasonableness, good faith and fair dealing;

(E) that the issuance of such Notes will not result in any default under this Indenture;

(F) that all consents or approvals of the Commission (or any successor agency) under the Public Utility Holding Company Act of 1935 and of any other federal or state regulatory agency required in connection with the Company's execution and delivery of this Indenture and such Notes have been

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obtained and are in full force and effect (except that no statement need be made with respect to state securities laws); and

(G) that all conditions that must be met by the Company to issue Notes under this Indenture have been met.

(3) An Officers' Certificate stating that (i) the Company is not, and upon the authentication by the Trustee of such Notes, will not be in default under any of the terms or covenants contained in this Indenture and (ii) all conditions that must be met by the Company to issue Notes under this Indenture have been met.

(d) No Note shall be entitled to any benefit under this Indenture or be valid or obligatory for any purpose unless there appears on such Note a certificate of authentication substantially in the form provided for herein executed by the Trustee by the manual signature of an authorized officer, and such certificate upon any Note shall be conclusive evidence, and the only evidence, that such Note has been duly authenticated and delivered hereunder and is entitled to the benefits of this Indenture.

(e) If all Notes of a series are not to be authenticated and issued at one time in connection with a Periodic Offering, the Company shall not be required to deliver the Company Order, Board Resolution, Officers' Certificate and Opinion of Counsel (including any of the foregoing that would be otherwise required pursuant to Section 15.05 hereof) described in Section 2.05(c) hereof at or prior to the authentication of each Note of such series, if such items are delivered at or prior to the time of authentication of the first Note of such series to be authenticated and issued.

Section 2.06 EXCHANGE AND REGISTRATION OF TRANSFER OF NOTES.

(a) Subject to Section 2.13 hereof, Notes of any series may be exchanged for one or more new Notes of the same series of any authorized denominations and of a like aggregate principal amount, series and Stated Maturity and having the same terms and Original Issue Date. Notes to be exchanged shall be surrendered at any of the offices or agencies to be maintained pursuant to Section 6.02 hereof, and the Trustee shall authenticate and deliver in exchange therefor the Note or Notes of such series which the Noteholder making the exchange shall be entitled to receive.

(b) The Trustee shall keep, at one of said offices or agencies, a register or registers in which, subject to such reasonable regulations as it may prescribe, the Trustee shall register or cause to be registered Notes and shall register or cause to be registered the transfer of Notes as in this Article II provided. Such register shall be in written form or in any other form capable of being converted into written form within a reasonable time. At all reasonable times, such register shall be open for inspection by the Company. Upon due presentment for registration of transfer of any Note at any such office or agency, the Company shall execute and the Trustee shall register, authenticate and deliver in the name of the transferee or transferees one or more new Notes of any authorized denominations and of a like aggregate principal amount, series and Stated Maturity and having the same terms and Original Issue Date.

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(c) All Notes presented for registration of transfer or for exchange, redemption or payment shall be duly endorsed by, or be accompanied by a written instrument or instruments of transfer in form satisfactory to the Company and the Trustee and duly executed by the Holder or the attorney in fact of such Holder duly authorized in writing.

(d) No service charge shall be made for any exchange or registration of transfer of Notes, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection therewith.

(e) The Trustee shall not be required to exchange or register the transfer of any Notes selected, called or being called for redemption (including Notes, if any, redeemable at the option of the Holder provided such Notes are then redeemable at such Holder's option) except, in the case of any Note to be redeemed in part, the portion thereof not to be so redeemed.

(f) If the principal amount, and applicable premium, of part, but not all of a Global Note is paid, then upon surrender to the Trustee of such Global Note, the Company shall execute, and the Trustee shall authenticate, deliver and register, a Global Note in an authorized denomination in aggregate principal amount equal to, and having the same terms, Original Issue Date and series as, the unpaid portion of such Global Note.

Section 2.07 MUTILATED, DESTROYED, LOST OR STOLEN NOTES.

(a) If any temporary or definitive Note shall become mutilated or be destroyed, lost or stolen, the Company shall execute, and upon its written request the Trustee shall authenticate and deliver, a new Note of like form and principal amount and having the same terms and Original Issue Date and bearing a number not contemporaneously outstanding, in exchange and substitution for the mutilated Note, or in lieu of and in substitution for the Note so destroyed, lost or stolen. In every case the applicant for a substituted Note shall furnish to the Company, the Trustee and any paying agent or Authenticating Agent such security or indemnity as may be required by them to save each of them harmless, and, in every case of destruction, loss or theft of a Note, the applicant shall also furnish to the Company and to the Trustee evidence to their satisfaction of the destruction, loss or theft of such Note and of the ownership thereof.

(b) The Trustee shall authenticate any such substituted Note and deliver the same upon the written request or authorization of any officer of the Company. Upon the issuance of any substituted Note, the Company may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto and any other expenses connected therewith. If any Note which has matured, is about to mature, has been redeemed or called for redemption shall become mutilated or be destroyed, lost or stolen, the Company may, instead of issuing a substituted Note, pay or authorize the payment of the same (without surrender thereof except in the case of a mutilated Note) if the applicant for such payment shall furnish to the Company, the Trustee and any paying agent or Authenticating Agent such security or indemnity as may be required by them to save each of them harmless and, in case of destruction, loss or theft, evidence satisfactory to the Company and the Trustee of the destruction, loss or theft of such Note and of the ownership thereof.

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(c) Every substituted Note issued pursuant to this Section 2.07 by virtue of the fact that any Note is mutilated, destroyed, lost or stolen shall constitute an additional contractual obligation of the Company, whether or not such destroyed, lost or stolen Note shall be found at any time, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Notes duly issued hereunder. All Notes shall be held and owned upon the express condition that, to the extent permitted by law, the foregoing provisions are exclusive with respect to the replacement or payment of mutilated, destroyed, lost or stolen Notes and shall preclude to the full extent permitted by applicable law any and all other rights or remedies with respect to the replacement or payment of negotiable instruments or other securities without their surrender.

Section 2.08 TEMPORARY NOTES. Pending the preparation of definitive Notes of any series, the Company may execute and the Trustee shall authenticate and deliver temporary Notes (printed, lithographed or otherwise reproduced). Temporary Notes shall be issuable in any authorized denomination and substantially in the form of the definitive Notes but with such omissions, insertions and variations as may be appropriate for temporary Notes, all as may be determined by the Company. Every such temporary Note shall be authenticated by the Trustee upon the same conditions and in substantially the same manner, and with the same effect, as the definitive Notes. Without unreasonable delay the Company shall execute and shall deliver to the Trustee definitive Notes of such series and thereupon any or all temporary Notes of such series shall be surrendered in exchange therefor at the corporate trust office of the Trustee, and the Trustee shall authenticate, deliver and register in exchange for such temporary Notes an equal aggregate principal amount of definitive Notes of such series. Such exchange shall be made by the Company at its own expense and without any charge therefor to the Noteholders. Until so exchanged, the temporary Notes of such series shall in all respects be entitled to the same benefits under this Indenture as definitive Notes of such series authenticated and delivered hereunder.

Section 2.09 CANCELLATION OF NOTES PAID, ETC. All Notes surrendered for the purpose of payment, redemption, exchange or registration of transfer shall be surrendered to the Trustee for cancellation and promptly cancelled by it and no Notes shall be issued in lieu thereof except as expressly permitted by this Indenture. The Company shall surrender to the Trustee any Notes so acquired by it and such Notes shall be cancelled by the Trustee. No Notes shall be authenticated in lieu of or in exchange for any Notes so cancelled.

Section 2.10 INTEREST RIGHTS PRESERVED. Each Note delivered under this Indenture upon transfer of or in exchange for or in lieu of any other Note shall carry all the rights to interest accrued and unpaid, and to accrue, which were carried by such other Note, and each such Note shall be so dated that neither gain nor loss of interest shall result from such transfer, exchange or substitution.

Section 2.11 SPECIAL RECORD DATE. If and to the extent that the Company fails to make timely payment or provision for timely payment of interest on any series of Notes (other than on an Interest Payment Date that is a Maturity date), that interest shall cease to be payable to the Persons who were the Noteholders of such series at the applicable Regular Record Date. In that event, when moneys become available for payment of the interest, the Trustee shall (a) establish a date of payment of such interest and a Special Record Date for the payment of that

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interest, which Special Record Date shall be not more than 15 or fewer than 10 days prior to the date of the proposed payment and (b) mail notice of the date of payment and of the Special Record Date not fewer than 10 days preceding the Special Record Date to each Noteholder of such series at the close of business on the 15th day preceding the mailing at the address of such Noteholder, as it appeared on the register for the Notes. On the day so established by the Trustee, the interest shall be payable to the Holders of the applicable Notes at the close of business on the Special Record Date.

Section 2.12 PAYMENT OF NOTES. Payment of the principal of and interest and premium on all Notes shall be payable as follows:

(a) On or before 9:30 a.m., New York City time, or such other time as shall be agreed upon between the Trustee and the Company, of the day on which payment of principal, interest and premium is due on any Global Note pursuant to the terms thereof, the Company shall deliver to the Trustee funds available on such date sufficient to make such payment, by wire transfer of immediately available funds or by instructing the Trustee to withdraw sufficient funds from an account maintained by the Company with the Trustee or such other method as is acceptable to the Trustee. On or before 12:00 noon, New York City time, or such other time as shall be agreed upon between the Trustee and the Depositary, of the day on which any payment of interest is due on any Global Note (other than at Maturity), the Trustee shall pay to the Depositary such interest in same day funds. On or before 1:00 p.m., New York City time or such other time as shall be agreed upon between the Trustee and the Depositary, of the day on which principal, interest payable at Maturity and premium, if any, is due on any Global Note, the Trustee shall deposit with the Depositary the amount equal to the principal, interest payable at Maturity and premium, if any, by wire transfer into the account specified by the Depositary. As a condition to the payment, at Maturity, of any part of the principal of, interest on, and applicable premium of any Global Note, the Depositary shall surrender, or cause to be surrendered, such Global Note to the Trustee, whereupon a new Global Note shall be issued to the Depositary pursuant to Section 2.06(f) hereof.

(b) With respect to any Note that is not a Global Note, principal, applicable premium and interest due at the Maturity of the Note shall be payable in immediately available funds when due upon presentation and surrender of such Note at the corporate trust office of the Trustee or at the authorized office of any paying agent in the Borough of Manhattan, The City and State of New York. Interest on any Note that is not a Global Note (other than interest payable at Maturity) shall be paid by check payable in clearinghouse funds mailed to the Holder thereof at such Holder's address as it appears on the register; provided that if the Trustee receives a written request from any Holder of Notes, the aggregate principal amount of which having the same Interest Payment Date equals or exceeds $10,000,000, on or before the applicable Regular Record Date for such Interest Payment Date, interest on such Note shall be paid by wire transfer of immediately available funds to a bank within the continental United States designated by such Holder in its request or by direct deposit into the account of such Holder designated by such Holder in its request if such account is maintained with the Trustee or any paying agent.

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Section 2.13 NOTES ISSUABLE IN THE FORM OF A GLOBAL NOTE.

(a) If the Company shall establish pursuant to Section 2.05 hereof that the Notes of a particular series are to be issued in the form of one or more Global Notes, then the Company shall execute and the Trustee shall, in accordance with Section 2.05 hereof and the Company Order delivered to the Trustee thereunder, authenticate and deliver such Global Note or Notes, which, unless otherwise specified in such Company Order, (i) shall represent, shall be denominated in an amount equal to the aggregate principal amount of, and shall have the same terms as, the outstanding Notes of such series to be represented by such Global Note or Notes, (ii) shall be registered in the name of the Depositary or its nominee, (iii) shall be delivered by the Trustee to the Depositary or pursuant to the Depositary's instruction and (iv) shall bear a legend substantially to the following effect: "This Note is a Global Note registered in the name of the Depositary (referred to herein) or a nominee thereof and, unless and until it is exchanged in whole for the individual Notes represented hereby as provided in the Indenture referred to below, this Global Note may not be transferred except as a whole by the Depositary to a nominee of the Depositary or by a nominee of the Depositary to the Depositary or another nominee of the Depositary or by the Depositary or any such nominee to a successor Depositary or a nominee of such successor Depositary. Unless this Global Note is presented by an authorized representative of The Depository Trust Company (55 Water Street, New York, New York), to the Trustee for registration of transfer, exchange or payment, and any certificate issued is registered in the name of Cede & Co. or such other name as requested by an authorized representative of The Depository Trust Company and any payment is made to Cede & Co., any transfer, pledge or other use hereof for value or otherwise by or to any person is wrongful since the registered owner hereof, Cede & Co., has an interest herein" or such other legend as may be required by the rules and regulations of the Depositary.

(b) (i) If at any time the Depositary for a Global Note notifies the Company that it is unwilling or unable to continue as Depositary for such Global Note or if at any time the Depositary for the Global Note shall no longer be eligible or in good standing under the Securities Exchange Act of 1934 or other applicable statute or regulation, the Company shall appoint a successor Depositary with respect to such Global Note. If a successor Depositary for such Global Note is not appointed by the Company within 90 days after the Company receives such notice or becomes aware of such ineligibility, the Company's election pursuant to Section 2.05(c)(vi) hereof shall no longer be effective with respect to the series of Notes evidenced by such Global Note and the Company shall execute, and the Trustee, upon receipt of a Company Order for the authentication and delivery of individual Notes of such series in exchange for such Global Note, shall authenticate and deliver, individual Notes of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of such Global Note in exchange for such Global Note. The Trustee shall not be charged with knowledge or notice of the ineligibility of a Depositary unless a Responsible Officer shall have actual knowledge thereof.

(ii) (A) The Company may at any time and in its sole discretion determine that all outstanding (but not less than all) Notes of a series issued or issuable in the form of one or more Global Notes shall no longer be represented by such Global Note or Notes. In such event the Company shall execute, and the Trustee, upon receipt of a Company Order for the authentication and delivery of individual Notes in exchange for such Global Note, shall

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authenticate and deliver individual Notes of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of such Global Note or Notes in exchange for such Global Note or Notes.

(B) Within seven days after the occurrence of an Event of Default with respect to any series of Global Notes, the Company shall execute, and the Trustee shall authenticate and deliver, Notes of such series in definitive registered form in any authorized denominations and in aggregate principal amount equal to the principal amount of such Global Notes in exchange for such Global Notes.

(iii) In any exchange provided for in any of the preceding two paragraphs, the Company will execute and the Trustee will authenticate and deliver individual Notes in definitive registered form in authorized denominations. Upon the exchange of a Global Note for individual Notes, such Global Note shall be cancelled by the Trustee. Notes issued in exchange for a Global Note pursuant to this Section shall be registered in such names and in such authorized denominations as the Depositary for such Global Note, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee. The Trustee shall deliver such Notes to the Depositary for delivery to the persons in whose names such Notes are so registered, or if the Depositary shall refuse or be unable to deliver such Notes, the Trustee shall deliver such Notes to the persons in whose names such Notes are registered, unless otherwise agreed upon between the Trustee and the Company, in which event the Company shall cause the Notes to be delivered to the persons in whose names such Notes are registered.

(c) Neither the Company, the Trustee, any Authenticating Agent nor any paying agent shall have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interests of a Global Note or for maintaining, supervising or reviewing any records relating to such beneficial ownership interest.

(d) Pursuant to the provisions of this subsection, at the option of the Trustee (subject to Section 2.04(a) hereof) and upon 30 days' written notice to the Depositary but not prior to the first Interest Payment Date of the respective Global Notes, the Depositary shall be required to surrender any two or more Global Notes which have identical terms, including, without limitation, identical maturities, interest rates and redemption provisions (but which may have differing Original Issue Dates) to the Trustee, and the Company shall execute and the Trustee shall authenticate and deliver to, or at the direction of, the Depositary a Global Note in principal amount equal to the aggregate principal amount of, and with all terms identical to, the Global Notes surrendered thereto and that shall indicate each applicable Original Issue Date and the principal amount applicable to each such Original Issue Date. The exchange contemplated in this subsection shall be consummated at least 30 days prior to any Interest Payment Date applicable to any of the Global Notes surrendered to the Trustee. Upon any exchange of any Global Note with two or more Original Issue Dates, whether pursuant to this Section or pursuant to
Section 2.06 or Section 3.03 hereof, the aggregate principal amount of the Notes with a particular Original Issue Date shall be the same before and after such exchange, after giving effect to any retirement of Notes and the Original Issue Dates applicable to such Notes occurring in connection with such exchange.

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Section 2.14 CUSIP AND ISIN NUMBERS. The Company in issuing Notes may use "CUSIP" or "ISIN" numbers (if then generally in use) and, if so used, the Trustee shall use "CUSIP" or "ISIN" numbers in notices of redemption as a convenience to holders of Notes; provided, that any such notice may state that no representation is made as to the correctness of such numbers either as printed on the Notes or contained in any notice of redemption and that reliance may be placed only on the other identification numbers printed on the Notes, and any such redemption shall not be affected by any defect in or omission of such numbers. The Company shall promptly notify the Trustee of any change in the "CUSIP" or "ISIN" numbers.

ARTICLE III

REDEMPTION OF NOTES

Section 3.01 APPLICABILITY OF ARTICLE. Such of the Notes of any series as are, by their terms, redeemable prior to their Stated Maturity at the option of the Company, may be redeemed by the Company at such times, in such amounts and at such prices as may be specified therein and in accordance with the provisions of this Article III.

Section 3.02 NOTICE OF REDEMPTION; SELECTION OF NOTES.

(a) The election of the Company to redeem any Notes shall be evidenced by a Board Resolution which shall be given with notice of redemption to the Trustee at least 45 days (or such shorter period acceptable to the Trustee in its sole discretion) prior to the redemption date specified in such notice.

(b) Notice of redemption to each Holder of Notes to be redeemed as a whole or in part shall be given by the Trustee, in the manner provided in
Section 15.10 hereof, no less than 30 or more than 60 days prior to the date fixed for redemption. Any notice which is given in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the Noteholder receives the notice. In any case, failure duly to give such notice, or any defect in such notice, to the Holder of any Note designated for redemption as a whole or in part shall not affect the validity of the proceedings for the redemption of any other Note.

(c) Each such notice shall identify the Notes to be redeemed (including "CUSIP" or "ISIN" numbers) and shall specify the date fixed for redemption, the places of redemption and the redemption price (or the method for calculation thereof) at which such Notes are to be redeemed, and shall state that (subject to subsection (e) of this section) payment of the redemption price of such Notes or portion thereof to be redeemed will be made upon surrender of such Notes at such places of redemption, that interest accrued to the date fixed for redemption will be paid as specified in such notice, and that from and after such date interest thereon shall cease to accrue. If less than all of a series of Notes having the same terms are to be redeemed, the notice shall specify the Notes or portions thereof to be redeemed. If any Note is to be redeemed in part only, the notice which relates to such Note shall state the portion of the principal amount thereof to be redeemed, and shall state that, upon surrender of such Note, a new Note or Notes having the same terms in aggregate principal amount equal to the unredeemed portion thereof will be issued.

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(d) Unless otherwise provided by a Company Order under Section 2.05 hereof, if less than all of a series of Notes is to be redeemed, the Trustee shall select in such manner as it shall deem appropriate and fair in its discretion the particular Notes to be redeemed in whole or in part and shall thereafter promptly notify the Company in writing of the Notes so to be redeemed. If less than all of a series of Notes represented by a Global Note is to be redeemed, the particular Notes or portions thereof of such series to be redeemed shall be selected by the Depositary for such series of Notes in such manner as the Depositary shall determine. Notes shall be redeemed only in denominations of $1,000, or such other denominations authorized by a Company Order pursuant to Section 2.05 hereof, provided that any remaining principal amount of a Note redeemed in part shall be a denomination authorized under this Indenture.

(e) If at the time of the mailing of any notice of redemption at the option of the Company, the Company shall not have irrevocably directed the Trustee to apply funds then on deposit with the Trustee or held by it and available to be used for the redemption of Notes to redeem all the Notes called for redemption, such notice, at the election of the Company, may state that it is conditional and subject to the receipt of the redemption moneys by the Trustee on or before the date fixed for redemption and that such notice shall be of no force and effect unless such moneys are so received on or before such date.

Section 3.03 PAYMENT OF NOTES ON REDEMPTION; DEPOSIT OF REDEMPTION PRICE.

(a) If notice of redemption for any Notes shall have been given as provided in Section 3.02 hereof and such notice shall not contain the language permitted at the Company's option under Section 3.02(e) hereof, such Notes or portions of Notes called for redemption shall become due and payable on the date and at the places stated in such notice at the applicable redemption price, together with interest accrued to the date fixed for redemption of such Notes. Interest on the Notes or portions thereof so called for redemption shall cease to accrue and such Notes or portions thereof shall be deemed not to be entitled to any benefit under this Indenture except to receive payment of the redemption price together with interest accrued thereon to the date fixed for redemption. Upon presentation and surrender of such Notes at the place of payment specified in such notice, such Notes or the specified portions thereof shall be paid and redeemed at the applicable redemption price, together with interest accrued thereon to the date fixed for redemption.

(b) If notice of redemption shall have been given as provided in
Section 3.02 hereof and such notice shall contain the language permitted at the Company's option under Section 3.02(e) hereof, such Notes or portions of Notes called for redemption shall become due and payable on the date and at the places stated in such notice at the applicable redemption price, together with interest accrued to the date fixed for redemption of such Notes, and interest on the Notes or portions thereof so called for redemption shall cease to accrue and such Notes or portions thereof shall be deemed not to be entitled to any benefit under this Indenture except to receive payment of the redemption price together with interest accrued thereon to the date fixed for redemption; provided that, in each case, the Company shall have deposited with the Trustee or a paying agent on or prior to 11:00 a.m. New York City time on such redemption date an amount sufficient to pay the redemption price together with interest accrued to the date fixed for redemption. Upon the Company making such deposit and, upon presentation and surrender of such Notes at such a place of payment in such notice specified, such Notes or the specified

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portions thereof shall be paid and redeemed at the applicable redemption price, together with interest accrued thereon to the date fixed for redemption. If the Company shall not make such deposit on or prior to the redemption date, the notice of redemption shall be of no force and effect and the principal on such Notes or specified portions thereof shall continue to bear interest as if the notice of redemption had not been given.

(c) No notice of redemption of Notes shall be mailed during the continuance of any Event of Default, except (1) that, when notice of redemption of any Notes has been mailed, the Company shall redeem such Notes but only if funds sufficient for that purpose have prior to the occurrence of such Event of Default been deposited with the Trustee or a paying agent for such purpose, and
(2) that notices of redemption of all outstanding Notes may be given during the continuance of an Event of Default.

(d) Upon surrender of any Note redeemed in part only, the Company shall execute, and the Trustee shall authenticate, deliver and register, a new Note or Notes of authorized denominations in aggregate principal amount equal to, and having the same terms, Original Issue Date or Dates and series as, the unredeemed portion of the Note so surrendered.

ARTICLE IV

SINKING FUNDS

Section 4.01 APPLICABILITY OF ARTICLE. The provisions of this Article shall be applicable to any sinking fund for the retirement of the Notes of any series, except as otherwise specified as contemplated by Section 2.05(c) hereof for Notes of such series.

The minimum amount of any sinking fund payment provided for by the terms of Notes of any series is herein referred to as a "mandatory sinking fund payment", and any payment in excess of such minimum amount provided for by the terms of Notes of any series is herein referred to as an "optional sinking fund payment". If provided for by the terms of Notes of any series, the cash amount of any sinking fund payment may be subject to reduction as provided in Section 4.02 hereof. Each sinking fund payment shall be applied to the redemption of Notes of the series in respect of which it was made as provided for by the terms of such Notes.

Section 4.02 SATISFACTION OF SINKING FUND PAYMENTS WITH NOTES. The Company
(a) may deliver Outstanding Notes (other than any previously called for redemption) of a series in respect of which a mandatory sinking fund payment is to be made and (b) may apply as a credit Notes of such series which have been redeemed either at the election of the Company pursuant to the terms of such Notes or through the application of permitted optional sinking fund payments pursuant to the terms of such Notes, in each case in satisfaction of all or any part of such mandatory sinking fund payment; provided, however, that no Notes shall be applied in satisfaction of a mandatory sinking fund payment if such Notes shall have been previously so applied. Notes so applied shall be received and credited for such purpose by the Trustee at the redemption price specified in such Notes for redemption through operation of the sinking fund and the amount of such mandatory sinking fund payment shall be reduced accordingly.

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Section 4.03 REDEMPTION OF NOTES FOR SINKING FUND. Not less than 45 days prior to each sinking fund payment date for the Notes of any series, the Company shall deliver to the Trustee an Officers' Certificate specifying:

(a) the amount of the next succeeding mandatory sinking fund payment for such series;

(b) the amount, if any, of the optional sinking fund payment to be made together with such mandatory sinking fund payment;

(c) the aggregate sinking fund payment;

(d) the portion, if any, of such aggregate sinking fund payment which is to be satisfied by the payment of cash; and

(e) the portion, if any, of such aggregate sinking fund payment which is to be satisfied by delivering and crediting Notes of such series pursuant to Section 4.02 hereof and stating the basis for such credit and that such Notes have not previously been so credited.

The Company shall also deliver to the Trustee any Notes to be so delivered. If the Company shall not deliver such Officers' Certificate, the next succeeding sinking fund payment for such series shall be made entirely in cash in the amount of the mandatory sinking fund payment. Not less than 30 days before each such sinking fund payment date the Trustee shall select the Notes to be redeemed upon such sinking fund payment date in the manner specified in Section 3.02(d) hereof and cause notice of the redemption thereof to be given in the name of and at the expense of the Company in the manner provided in Section 3.02 hereof. Such notice having been duly given, the redemption of such Notes shall be made upon the terms and in the manner stated in Section 3.03 hereof.

ARTICLE V

SATISFACTION AND DISCHARGE; UNCLAIMED MONEYS

Section 5.01 SATISFACTION AND DISCHARGE OF INDENTURE. This Indenture shall upon the request of the Company cease to be of further effect with respect to the Notes of any series (except as to any surviving rights of registration of transfer or exchange of Notes of such series herein expressly provided for), and the Trustee, at the expense of the Company, shall execute proper instruments acknowledging satisfaction and discharge of this Indenture, when:

(a) either:

(i) all Notes of such series previously authenticated and delivered (other than Notes of such series which have been destroyed, lost or stolen and which have been replaced or paid) have been delivered to the Trustee for cancellation; or

(ii) all the Notes of such series not previously delivered to the Trustee for cancellation have become due and payable (whether at stated maturity, early redemption or

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otherwise), and the Company has deposited, or caused to be deposited, irrevocably with the Trustee as funds in trust solely for the benefit of the Holders of the Notes of such series an amount in cash sufficient to pay principal of, premium, if any, and interest on all outstanding Notes of such series;

(b) the Company has paid or caused to be paid all other sums payable hereunder by the Company with respect to the Notes of such series; and

(c) the Company has delivered to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that all conditions precedent herein provided for relating to the satisfaction and discharge of this Indenture with respect to the Notes of such series have been complied with.

Notwithstanding the satisfaction and discharge of this Indenture with respect to the Notes of any or all series, the obligations of the Company to the Trustee under Section 9.06 hereof shall survive, and, if money will have been deposited with the Trustee pursuant to subclause (ii) of clause (a) of this Section 5.01, the obligations of the Trustee under Sections 5.02 and 5.05 hereof shall survive.

Section 5.02 APPLICATION OF TRUST FUNDS; INDEMNIFICATION.

(a) Subject to the provisions of Section 5.05 hereof, all money and U.S. Government Obligations deposited with the Trustee pursuant to Section 5.01, 5.03 or 5.04 hereof and all money received by the Trustee in respect of U.S. Government Obligations deposited with the Trustee pursuant to Sections 5.01, 5.03 or 5.04 hereof, shall be held in trust and applied by it, in accordance with the provisions of the Notes of any particular series and this Indenture, to the payment, either directly or through any paying agent as the Trustee may determine, to the persons entitled thereto, of the principal, premium, if any, and interest for whose payment such money has been deposited with or received by the Trustee.

(b) The Company shall pay and shall indemnify the Trustee against any tax, fee or other charge imposed on or assessed against U.S. Government Obligations deposited pursuant to Sections 5.01, 5.03 or 5.04 hereof or the interest, premium, if any, and principal received in respect of such obligations other than any payable by or on behalf of Holders.

(c) The Trustee shall deliver or pay to the Company from time to time upon the request of the Company any U.S. Government Obligations or money held by it as provided in Sections 5.01, 5.03 or 5.04 hereof which, in the opinion of a nationally recognized firm of independent certified public accountants expressed in a written certification thereof delivered to the Trustee, are then in excess of the amount thereof which then would have been required to be deposited for the purpose for which such U.S. Government Obligations or money were deposited or received. This provision shall not authorize the sale by the Trustee of any U.S. Government Obligations held under this Indenture.

Section 5.03 LEGAL DEFEASANCE. The Company shall be deemed to have been discharged from its obligations with respect to all of the outstanding Notes of any series on the day after the date of the deposit referred to in subparagraph
(i) hereof, and the provisions of this Indenture, as it relates to the outstanding Notes of such series, shall no longer be in effect (and

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the Trustee, at the expense of the Company, shall, upon the request of the Company, execute proper instruments acknowledging the same), except as to:

(a) the rights of Holders of the Notes of such series to receive, solely from the trust funds described in subparagraph (i) below, payments of the principal of, premium, if any, or interest on the outstanding Notes of such series on the date such payments are due;

(b) the Company's obligations with respect to the Notes of such series under Sections 2.06, 2.07, 2.13, 6.02 and 6.04 hereof; and

(c) the rights, powers, trust and immunities of the Trustee hereunder and the duties of the Trustee under Section 5.02 hereof and the duty of the Trustee to authenticate Notes of such series issued on registration of transfer of exchange;

provided that the following conditions shall have been satisfied:

(i) the Company shall have deposited, or caused to be deposited, irrevocably with the Trustee as funds in trust for the purpose of making the following payments, specifically pledged as security for and dedicated solely to the benefit of the Holders of the Notes of such series, cash in U.S. dollars and/or U.S. Government Obligations which through the payment of interest and principal in respect thereof, in accordance with their terms, will provide (without reinvestment), not later than one day before the due date of any payment of money, an amount in cash, sufficient, in the opinion of a nationally recognized firm of independent public accountants expressed in a written certification thereof delivered to the Trustee, to pay principal of, premium, if any, and interest on all the Notes of such series on the dates such payments of principal, premium, if any, or interest are due to maturity or redemption;

(ii) no Event of Default or event which with the giving of notice or lapse of time or both would become an Event of Default with respect to the Notes of such series shall have occurred and be continuing on the date of such deposit and 91 days shall have passed after the deposit has been made, and, during such 91 day period, no Default with respect to the Notes of such series specified in
Section 8.01(a)(5) or (6) hereof with respect to the Company occurs which is continuing at the end of such period;

(iii) the Company shall have delivered to the Trustee an Officers' Certificate and an Opinion of Counsel to the effect that (A) the Company has received from, or there has been published by, the Internal Revenue Service a ruling, or (B) since the date of execution of this Indenture, there has been a change in the applicable federal income tax law, in either case to the effect that, and based thereon such Opinion of Counsel shall confirm that, the Holders of the Notes of such series will not recognize income, gain or loss for federal income tax purposes as a result of such deposit, defeasance and discharge and will be subject to federal income tax in the same amounts, in the same manner and at the same times as would have been the case if such deposit, defeasance and discharge had not occurred;

(iv) the Company shall have delivered to the Trustee an Officers' Certificate stating that the deposit was not made by the Company with the intent of preferring the Holders of the Notes of such series over any other creditors of the Company or with the intent of defeating, hindering, delaying or defrauding any other creditors of the Company;

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(v) such deposit shall not cause the Trustee to have a conflicting interest within the meaning of the TIA with respect to any securities of the Company or result in the trust arising from such deposit constituting an "investment company" (as defined in the Investment Company Act of 1940, as amended); and

(vi) the Company shall have delivered to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that all conditions precedent relating to the defeasance contemplated by this Section 5.03 have been complied with.

Subject to compliance with this Article V, the Company may exercise its option under this Section 5.03 notwithstanding the prior exercise of its option under
Section 5.04 with respect to the Notes of any series. Following a defeasance, payment of the Notes of such series may not be accelerated because of an Event of Default.

Section 5.04 COVENANT DEFEASANCE. On and after the day after the date of the deposit referred to in subparagraph (a) hereof, the Company may omit to comply with any term, provision or condition set forth under Section 6.05 and Article XII hereof as well as any additional covenants contained in a supplemental indenture hereto (and the failure to comply with any such provisions shall not constitute a Default or Event of Default under Section 8.01 hereof) and the occurrence of any event described in clause (3) and (4) of
Section 8.01(a) hereof shall not constitute a Default or Event of Default hereunder, with respect to the Notes of any series, provided that the following conditions shall have been satisfied:

(a) with reference to this Section 5.04, the Company has deposited, or caused to be deposited, irrevocably (except as provided in Section 5.05 hereof) with the Trustee as funds in trust, specifically pledged as security for, and dedicated solely to, the benefit of the Holders of the Notes of such series, cash in U.S. dollars and/or U.S. Government Obligations which through the payment of principal and interest in respect thereof, in accordance with their terms, will provide (without reinvestment), not later than one day before the due date of any payment of money, an amount in cash, sufficient, in the opinion of a nationally recognized firm of independent certified public accountants expressed in a written certification thereof delivered to the Trustee, to pay principal, premium, if any, and interest on all the Notes of such series on the dates such payments of principal, premium, if any, and interest are due to maturity or redemption;

(b) no Event of Default or event which with the giving of notice or lapse of time or both would become an Event of Default with respect to the Notes of such series shall have occurred and be continuing on the date of such deposit and 91 days shall have passed after the deposit has been made, and, during such 91 day period, no Default with respect to the Notes of such series specified in
Section 8.01(a)(5) or (6) hereof with respect to the Company occurs which is continuing at the end of such period;

(c) the Company shall have delivered to the Trustee an Opinion of Counsel confirming that Holders of the Notes of such series will not recognize income, gain or loss for federal income tax purposes as a result of such deposit and defeasance and will be subject to federal income tax in the same amounts, in the same manner and at the same times as would have been the case if such deposit and defeasance had not occurred;

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(d) the Company shall have delivered to the Trustee an Officers' Certificate stating the deposit was not made by the Company with the intent of preferring the Holders of the Notes of such series over any other creditors of the Company or with the intent of defeating, hindering, delaying or defrauding any other creditors of the Company;

(e) such deposit shall not cause the Trustee to have a conflicting interest within the meaning of the TIA with respect to any securities of the Company or result in the trust arising from such deposit constituting an "investment company" (as defined in the Investment Company Act of 1940, as amended);

(f) the Company shall have delivered to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that all conditions precedent herein provided for relating to the defeasance contemplated by this
Section 5.04 have been complied with; and

(g) following a covenant defeasance, payment of the Notes of any series may not be accelerated because of an Event of Default specified in Sections 8.01(a)(5) and (6) or by reference to Sections 6.05 and 8.01(a)(3) and
(4) and Article XII hereof.

Section 5.05 REPAYMENT TO COMPANY. The Trustee and the paying agent shall pay to the Company upon request any money held by them for the payment of principal, premium, if any, or interest that remains unclaimed for two years after the date upon which such payment shall have become due. After payment to the Company, Holders of the Notes of such series entitled to the money must look to the Company for payment as general creditors unless an applicable abandoned property law designates another Person.

ARTICLE VI

PARTICULAR COVENANTS OF THE COMPANY

Section 6.01 PAYMENT OF PRINCIPAL AND INTEREST. The Company covenants and agrees for the benefit of the Holders of the Notes of any series that it will duly and punctually pay or cause to be paid the principal of and any premium and interest, if any, on, such Notes at the places, at the respective times and in the manner provided in such Notes or in this Indenture.

Section 6.02 OFFICES FOR PAYMENTS, ETC. So long as the Notes of any series are outstanding hereunder, the Company will maintain in the Borough of Manhattan, The City of New York, State of New York or St. Louis, Missouri an office or agency where the Notes of such series may be presented for payment, for exchange as in this Indenture provided and for registration of transfer as in this Indenture provided.

The Company will maintain in the Borough of Manhattan, The City of New York, State of New York or St. Louis, Missouri an office or agency where notices and demands to or upon the Company in respect of the Notes of any series or this Indenture may be served.

The Company will give to the Trustee prompt written notice of the location of each such office or agency and of any change of location thereof. In case the Company shall fail to maintain any office or agency required by this Section to be located in the Borough of

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Manhattan, The City of New York, State of New York or St. Louis, Missouri or shall fail to give such notice of the location or of any change in the location of any of the above offices or agencies, presentations and demands may be made and notices may be served at the Corporate Trust Office of the Trustee, and, in such event, the Trustee shall act as the Company's agent to receive all such presentations, surrenders, notices and demands.

The Company may from time to time designate one or more additional offices or agencies where the Notes of any series may be presented for payment, for exchange as in this Indenture provided and for registration of transfer as in this Indenture provided, and the Company may from time to time rescind any such designation; provided, however, that no such designation or rescission shall in any manner relieve the Company of its obligation to maintain any office or agency provided for in this Section. The Company will give to the Trustee prompt written notice of any such designation or rescission thereof and of any change in the location of any such other office or agency.

Section 6.03 APPOINTMENT TO FILL A VACANCY IN OFFICE OF TRUSTEE. The Company, whenever necessary to avoid or fill a vacancy in the office of Trustee, will appoint, in the manner provided in Section 9.11, a Trustee, so that there shall at all times be a Trustee hereunder.

Section 6.04 PROVISION AS TO PAYING AGENT. The Trustee shall be the paying agent for the Notes and, at the option of the Company, the Company may appoint additional paying agents (including without limitation itself or its Subsidiary unless an Event of Default has occurred and is continuing). Whenever the Company shall appoint a paying agent other than the Trustee with respect to the Notes, it will cause such paying agent to execute and deliver to the Trustee an instrument in which such agent shall agree with the Trustee, subject to the provisions of this Section:

(1) that such paying agent will hold all sums received by it as such agent for the payment of the principal of or interest, if any, on the Notes (whether such sums have been paid to it by the Company or by any other obligor on the Notes) in trust for the benefit of the Holders of the Notes, or of the Trustee until such sums shall be paid to such Holders or otherwise disposed of as herein provided;

(2) that such paying agent will give the Trustee notice of any failure by the Company (or by any other obligor on Notes) to make any payment of the principal of, premium if any, or interest on the Notes when the same shall be due and payable; and

(3) that such paying agent will at any time during the continuance of any such failure, upon the written request of the Trustee, forthwith pay to the Trustee all sums so held in trust by such paying agent.

The Company will, on or prior to each due date of the principal of and any premium, if any, or interest on the Notes, deposit with the paying agent a sum sufficient to pay such principal and any premium or interest so becoming due, such sum to be held in trust for the benefit of the Holders of the Notes entitled to such principal of and any premium or interest, and (unless such paying agent is the Trustee) the Company will promptly notify the Trustee of any failure to take such action.

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If the Company or its Subsidiary shall act as its own paying agent with respect to the Notes, it will, on or before each due date of the principal of (and premium, if any) or interest, if any, on the Notes, set aside, segregate and hold in trust for the benefit of the Holders of the Notes, a sum sufficient to pay such principal (and premium, if any) or interest, if any, so becoming due until such sums shall be paid to such Holders or otherwise disposed of as herein provided. The Company will promptly notify the Trustee of any failure to take such action.

The Company may at any time pay or cause to be paid to the Trustee all sums held in trust by it or any paying agent hereunder, as required by this Section, such sums to be held by the Trustee upon the trusts herein contained, and, upon such payment by any paying agent to the Trustee, such paying agent shall be released from all further liability with respect to such money.

Anything in this Section to the contrary notwithstanding, the agreement to hold sums in trust as provided in this Section is subject to the provisions of Sections 5.03 and 5.04.

Section 6.05 CORPORATE EXISTENCE. Subject to the rights of the Company under Article XII, the Company shall do or cause to be done all things necessary to preserve and keep in full force and effect its corporate existence and the rights (charter and statutory) and franchises of the Company; provided, however, that the Company shall not be required to preserve any such right or franchise if, in the judgment of the Company, the preservation thereof is no longer desirable in the conduct of the business of the Company.

Section 6.06 CERTIFICATES AND NOTICE TO TRUSTEE. The Company shall, on or before December 1 of each year, commencing December 1, 2002, deliver to the Trustee a certificate from its principal executive officer, principal financial officer or principal accounting officer covering the preceding calendar year and stating whether or not, to the knowledge of such Person, the Company has complied with all conditions and covenants under this Indenture, and, if not, describing in reasonable detail any failure by the Company to comply with any such conditions or covenants. For purposes of this Section, compliance shall be determined without regard to any period of grace or requirement of notice provided under this Indenture.

ARTICLE VII

NOTEHOLDER LISTS AND REPORTS BY
THE COMPANY AND THE TRUSTEE

Section 7.01 COMPANY TO FURNISH NOTEHOLDER LISTS. The Company and any other obligor on the Notes shall furnish or cause to be furnished to the Trustee a list in such form as the Trustee may reasonably require of the names and addresses of the Holders of the Notes:

(a) semi-annually and not more than 15 days after each Regular Record Date for each Interest Payment Date that is not a Maturity date, as of such Regular Record Date, and such list need not include information received after such date; and

(b) at such other times as the Trustee may request in writing, within 30 days after receipt by the Company of any such request, as of a date not more than 15 days prior to the time

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such information is furnished, and such list need not include information received after such date;

provided that if and so long as the Trustee shall be the registrar for the Notes, such list shall not be required to be furnished.

Section 7.02 PRESERVATION AND DISCLOSURE OF NOTEHOLDER LISTS.

(a) The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the Holders of the Notes (i) contained in the most recent lists furnished to it as provided in Section 7.01, (ii) received by it in the capacity of registrar for the Notes, if so acting, and (iii) filed with it within the two preceding years pursuant to Section 7.04(d)(2). The Trustee may destroy any list furnished to it as provided in Section 7.01 upon receipt of a new list so furnished.

(b) In case three or more Holders of Notes (hereinafter referred to as "applicants") apply in writing to the Trustee and furnish to the Trustee reasonable proof that each such applicant has owned a Note for a period of at least six months preceding the date of such application, and such application states that the applicants desire to communicate with other Holders of Notes with respect to their rights under this Indenture or under the Notes and such application is accompanied by a copy of the form of proxy or other communication which such applicants propose to transmit, then the Trustee shall, within five Business Days after the receipt of such application, at its election, either

(i) afford to such applicants access to the information preserved at the time by the Trustee in accordance with the provisions of subsection (a) of this Section; or

(ii) inform such applicants as to the approximate number of Holders whose names and addresses appear in the information preserved at the time by the Trustee, in accordance with the provisions of such subsection (a) and as to the approximate cost of mailing to such Holders the form of proxy or other communication, if any, specified in such application.

If the Trustee shall elect not to afford to such applicants access to such information, the Trustee shall, upon the written request of such applicants, mail to each Holder of Notes, whose name and address appears in the information preserved at the time by the Trustee in accordance with the provisions of such subsection (a) a copy of the form of proxy or other communication which is specified in such request, with reasonable promptness after a tender to the Trustee of the material to be mailed and of payment, or provision for the payment, of the reasonable expenses of mailing, unless within five days after such tender the Trustee shall mail to such applicants and file with the Commission, together with a copy of the material to be mailed, a written statement to the effect that, in the opinion of the Trustee, such mailing would be contrary to the best interests of the Holders or would be in violation of applicable law. Such written statement shall specify the basis of such opinion. If the Commission, after opportunity for a hearing upon the objections specified in the written statement so filed, shall enter an order refusing to sustain any of such objections or if, after the entry of an order sustaining one or more of such objections, the Commission shall find, after notice and opportunity for hearing, that all the objections so sustained have been met, and shall enter an order so declaring, the Trustee shall mail copies of

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such material to all such Holders with reasonable promptness after the entry of such order and the renewal of such tender; otherwise the Trustee shall be relieved of any obligation or duty to such applicants respecting their application.

(c) Each and every Holder of a Note, by receiving and holding the same, agrees with the Company and the Trustee that neither the Company nor the Trustee nor any agent of the Company or the Trustee shall be held accountable by reason of the disclosure of any such information as to the names and addresses of the Holders of Notes in accordance with the provisions of subsection (b) of this Section, regardless of the source from which such information was derived, and that the Trustee shall not be held accountable by reason of mailing any material pursuant to a request made under such subsection (b).

Section 7.03 REPORTS BY THE COMPANY. The Company shall:

(a) file with the Trustee, within 15 days after the Company is required to file the same with the Commission, copies of the annual reports and of the information, documents and other reports (or copies of such portions of any of the foregoing as the Commission may from time to time by rules and regulations prescribe) which the Company may be required to file with the Commission pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934; or, if the Company is not required to file information, documents or reports pursuant to either of said Sections, then it will file with the Trustee and the Commission, in accordance with rules and regulations prescribed from time to time by the Commission, such of the supplementary and periodic information, documents and reports which may be required pursuant to Section 13 of the Securities Exchange Act of 1934 in respect of a security listed and registered on a national securities exchange as may be prescribed from time to time in such rules and regulations;

(b) file with the Trustee and the Commission, in accordance with rules and regulations prescribed from time to time by the Commission, such additional information, documents and reports with respect to compliance by the Company with the conditions and covenants of this Indenture as may be required from time to time by such rules and regulations. Filing of such information, documents and reports with the Trustee is for informational purposes only and the Trustee's receipt of such shall not constitute constructive notice of any information contained therein or determinable from information contained therein, including the Company's compliance with any of its covenants hereunder (as to which the Trustee is entitled to rely exclusively on Officers' Certificates); and

(c) transmit by mail to all Holders of Notes, within 30 days after the filing thereof with the Trustee in the manner and to the extent provided in
Section 7.04(d), such summaries of any information, documents and reports required to be filed by the Company pursuant to paragraphs (a) and (b) of this
Section as may be required by rules and regulations prescribed from time to time by the Commission.

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Section 7.04 REPORTS BY THE TRUSTEE.

(a) Annually, not later than August 15 of each year, the Trustee shall transmit by mail a brief report dated as of such date that complies with
Section 313(a) of the TIA (to the extent required by such Section).

(b) The Trustee shall from time to time transmit by mail brief reports that comply, both in content and date of delivery, with Section 313(b) of the TIA (to the extent required by such Section).

(c) A copy of each such report filed pursuant to this section shall, at the time of such transmission to such Holders, be filed by the Trustee with each stock exchange upon which any Notes are listed and also with the Commission. The Company will notify the Trustee promptly in writing upon the listing of such Notes on any stock exchange or any delisting thereof.

(d) Reports pursuant to this Section shall be transmitted

(1) by mail to all Holders of Notes, as their names and addresses appear in the register for the Notes;

(2) by mail to such Holders of Notes as have, within the two years preceding such transmission, filed their names and addresses with the Trustee for such purpose;

(3) by mail, except in the case of reports pursuant to Section 7.04(b) and (c) hereof, to all Holders of Notes whose names and addresses have been furnished to or received by the Trustee pursuant to Section 7.01 and 7.02(a)(ii) hereof; and

(4) at the time such report is transmitted to the Holders of the Notes, to each exchange on which Notes are listed and also with the Commission.

ARTICLE VIII

REMEDIES OF THE TRUSTEE AND NOTEHOLDERS
ON EVENTS OF DEFAULT

Section 8.01 EVENTS OF DEFAULT.

(a) If one or more of the following Events of Default with respect to the Notes of any series shall have occurred and be continuing:

(1) default in the payment of any installment of interest upon any Note of such series as and when the same shall become due and payable, and continuance of such default for a period of thirty (30) days;

(2) default in the payment of the principal of or any premium on any Note of such series as and when the same shall become due and payable;

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(3) failure on the part of the Company duly to observe or perform any other covenants or agreements on the part of the Company contained in this Indenture (other than a covenant or agreement that has been expressly included in this Indenture solely for the benefit of one or more series of Notes other than such series) for a period of sixty (60) days after the date on which written notice specifying such failure, stating that such notice is a "Notice of Default" hereunder and demanding that the Company remedy the same, shall have been given to the Company by the Trustee by registered mail, or to the Company and the Trustee by the Holders of not less than 33% in aggregate principal amount of the Notes of such series at the time outstanding;

(4) failure to pay when due and payable after the expiration of any applicable grace period, any portion of the principal of Debt of the Company in excess of $25,000,000 (including a default with respect to Notes of any other series), or acceleration of such Debt for another default thereunder, without such Debt having been discharged, or such acceleration having been rescinded or annulled, within 30 days after written notice to the Company by the Trustee or to the Company and the Trustee by the holders of at least 33% in aggregate principal amount of the Notes of such series at the time outstanding;

(5) a court having jurisdiction in the premises shall enter a decree or order for relief in respect of the Company in an involuntary case under any applicable bankruptcy, insolvency or other similar law now or hereafter in effect, adjudging the Company a bankrupt or insolvent, or approving as properly filed a petition seeking reorganization, arrangement, adjustment or composition of or in respect of the Company under any applicable law, or appointing a receiver, liquidator, assignee, custodian, trustee or sequestrator (or similar official) of the Company or for any substantial part of the property of the Company, or ordering the winding up or liquidation of the affairs of the Company, and such decree or order shall remain unstayed and in effect for a period of sixty (60) consecutive days;

(6) the Company shall commence a voluntary case or proceeding under any applicable bankruptcy, insolvency, reorganization or other similar law now or hereafter in effect or any other case or proceeding to be adjudicated a bankrupt or insolvent, or consent to the entry of a decree or order for relief in an involuntary case under any such law, or to the commencement of any bankruptcy or insolvency case or proceeding against it, or the filing by it of a petition or answer or consent seeking reorganization or relief under any applicable law, or consent to the filing of such petition or to the appointment or taking possession by a receiver, liquidator, assignee, custodian, trustee or sequestrator (or similar official) of the Company or for any substantial part of the property of the Company, or make any general assignment for the benefit of creditors, or the notice by it in writing of its inability to pay its debts generally as they become due, or the taking of any corporate action by the Company in furtherance of any such action; or

(7) any other Event of Default specified with respect to Notes of any series pursuant to Section 2.05 hereof;

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then, unless the principal of and interest on all of the Notes shall have already become due and payable, either the Trustee or the Holders of a majority in aggregate principal amount of the Notes of such series then outstanding, by notice in writing to the Company (and to the Trustee if given by such Holders), may declare the principal of and interest on all the Notes of such series to be due and payable immediately and upon any such declaration the same shall become immediately due and payable, anything in this Indenture or in the Notes of such series contained to the contrary notwithstanding; provided, however, that if an Event of Default shall have occurred and be continuing with respect to more than one series of Notes, the Trustee or the Holders of a majority in aggregate principal amount of the Outstanding Notes of all such series, considered as one class, may make such declaration of acceleration, and not the Holders of the Notes of any one of such series.

The foregoing paragraph, however, is subject to the condition that if, at any time after the principal of and interest on the Notes of any series shall have been so declared due and payable, and before any judgment or decree for the payment of the moneys due shall have been obtained or entered as hereinafter provided, the Company shall pay or shall deposit with the Trustee a sum sufficient to pay all matured installments of interest upon all of the Notes of such series and the principal of and any premium on any and all Notes of such series which shall have become due otherwise than by acceleration (with interest on overdue installments of interest, to the extent that payment of such interest is enforceable under applicable law, and on such principal and applicable premium at the rate borne by the Notes of such series to the date of such payment or deposit) and all sums paid or advanced by the Trustee hereunder, the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel, and any other amounts due the Trustee under Section 9.06 hereof, and any and all Events of Default, other than the non-payment of principal of and accrued interest on any Notes which shall have become due solely by acceleration of maturity, shall have been cured or waived, then and in every such case such payment or deposit shall cause an automatic waiver of the Event of Default and its consequences and shall cause an automatic rescission and annulment of the acceleration of the Notes of such series; but no such waiver or rescission and annulment shall extend to or shall affect any subsequent default, or shall impair any right consequent thereon.

(b) If the Trustee shall have proceeded to enforce any right under this Indenture and such proceedings shall have been discontinued or abandoned because of such rescission or annulment or for any other reason or shall have been determined adversely to the Trustee, then and in every such case the Company and the Trustee shall be restored respectively to their several positions and rights hereunder, and all rights, remedies and powers of the Company and the Trustee shall continue as though no such proceeding had been taken.

Section 8.02 COLLECTION OF INDEBTEDNESS BY TRUSTEE; TRUSTEE MAY PROVE DEBT.

(a) The Company covenants that if an Event of Default described in clause (a)(1) or (a)(2) of Section 8.01 hereof shall have occurred and be continuing, then, upon demand of the Trustee, the Company shall pay to the Trustee, for the benefit of the Holders of the Notes of the series with respect to which Event of Default shall have occurred and is continuing, the whole amount that then shall have so become due and payable on all such Notes for principal or interest, as the case may be, with interest upon the overdue principal and any premium and (to the extent that payment of such interest is enforceable under applicable law) upon the overdue

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installments of interest at the rate borne by such Notes; and, in addition thereto, such further amounts as shall be sufficient to cover the costs and expenses of collection, including reasonable compensation to the Trustee, its agents, attorneys and counsel, any expenses or liabilities incurred by the Trustee hereunder other than through its negligence or bad faith. Until such demand is made by the Trustee, the Company may pay the principal of and interest on such Notes to the Holders, whether or not such Notes be overdue.

(b) In case the Company shall fail forthwith to pay such amounts upon such demand, the Trustee, in its own name and as trustee of an express trust, shall be entitled and empowered to institute any actions or proceedings at law or in equity for the collection of the sums so due and unpaid, and may enforce any such judgment or final decree against the Company or any other obligor on such Notes and collect in the manner provided by law out of the property of the Company or any other obligor on such Notes wherever situated, the moneys adjudged or decreed to be payable.

(c) In case there shall be pending proceedings relative to the Company or any other obligor upon the Notes under Title 11 of the United States Code or any other applicable Federal or state bankruptcy, insolvency or other similar law, or in case a receiver, assignee or trustee in bankruptcy or reorganization, liquidator, sequestrator or similar official shall have been appointed for or taken possession of the Company or its property or such other obligor, or in case of any other comparable judicial proceedings relative to the Company or such other obligor, or to the creditors or property of the Company or such other obligor, the Trustee, irrespective of whether the principal of the Notes shall then be due and payable as therein expressed or by declaration or otherwise and irrespective of whether the Trustee shall have made any demand pursuant to the provisions of this Section, shall be entitled and empowered, by intervention in such proceedings or otherwise:

(1) to file and prove a claim or claims for the whole amount of the principal and interest owing and unpaid in respect of the Notes, and to file such other papers or documents as may be necessary or advisable in order to have the claims of the Trustee and of the Noteholders allowed in any judicial proceedings relative to the Company or such other obligor, or to the creditors or property of the Company or such other obligor; and

(2) to collect and receive any moneys or other property payable or deliverable on any such claims, and to distribute all amounts received with respect to the claims of the Noteholders and of the Trustee on their behalf; and any trustee, receiver, liquidator, custodian or other similar official is hereby authorized by each of the Noteholders to make payments to the Trustee, and, in the event that the Trustee shall consent to the making of the payments directly to the Noteholders, to pay to Trustee such amounts due pursuant to Section 9.06 hereof.

(d) Nothing herein contained shall be deemed to authorize the Trustee to authorize or consent to or vote for or accept or adopt on behalf of any Holder any plan of reorganization, arrangement, adjustment or composition affecting the Notes of any series or the rights of any Holder thereof, or to authorize the Trustee to vote in respect of the claim of any

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Holder in any such proceeding except to vote for the election of a trustee in bankruptcy or similar person.

(e) All rights of action and of asserting claims under this Indenture, or under any of the Notes may be prosecuted and enforced by the Trustee without the possession of any of the Notes or the production thereof at any trial or other proceedings relative thereto, and any such action or proceedings instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment, subject to the payment of the expenses, disbursements and compensation of the Trustee and its agents, attorneys and counsel, shall be for the ratable benefit of the Holders of the Notes in respect of which such action was taken.

(f) In any proceedings brought by the Trustee (and also any proceedings involving the interpretation of any provision of this Indenture to which the Trustee shall be a party), the Trustee shall be held to represent all the Holders of the Notes in respect to which action was taken, and it shall not be necessary to make any Holders of such Notes parties to any such proceedings.

Section 8.03 APPLICATION OF PROCEEDS. Any moneys collected by the Trustee with respect to any of the Notes pursuant to this Article shall be applied in the following order, at the date or dates fixed by the Trustee for the distribution of such moneys, upon presentation of the several Notes, and stamping thereon the payment, if only partially paid, and upon surrender thereof if fully paid.

FIRST: To the payment of all amounts due to the Trustee pursuant to
Section 9.06 hereof;

SECOND: In case the principal of the outstanding Notes in respect of which such moneys have been collected shall not have become due and be unpaid, to the payment of interest on the Notes, in the order of the maturity of the installments of such interest, with interest (to the extent allowed by law) upon the overdue installments of interest at the rate borne by the Notes, such payments to be made ratably to the persons entitled thereto, and then to the payment to the Holders entitled thereto of the unpaid principal of and applicable premium on any of the Notes which shall have become due (other than Notes previously called for redemption for the payment of which moneys are held pursuant to the provisions of this Indenture), whether at stated maturity or by redemption, in the order of their due dates, beginning with the earliest due date, and if the amount available is not sufficient to pay in full all Notes due on any particular date, then to the payment thereof ratably, according to the amounts of principal and applicable premium due on that date, to the Holders entitled thereto, without any discrimination or privilege;

THIRD: In case the principal of the outstanding Notes in respect of which such moneys have been collected shall have become due, by declaration or otherwise, to the payment of the whole amount then owing and unpaid upon the Notes for principal and any premium and interest thereon, with interest on the overdue principal and any premium and (to the extent allowed by law) upon overdue installments of interest at the rate borne by the Notes; and in case such moneys shall be insufficient to pay in full the whole amount so due and unpaid upon the Notes, then to the payment of such principal and any premium and interest without preference or priority of principal and any premium over interest, or of interest over principal and any

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premium or of any installment of interest over any other installment of interest, or of any Note over any other Note, ratably to the aggregate of such principal and any premium and accrued and unpaid interest; and

FOURTH: To the payment of the remainder, if any, to the Company or its successors or assigns, or to whomsoever may lawfully be entitled to the same, or as a court of competent jurisdiction may determine.

Section 8.04 LIMITATIONS ON SUITS BY NOTEHOLDERS.

(a) No Holder of any Note of any series shall have any right by virtue of or by availing of any provision of this Indenture to institute any suit, action or proceeding in equity or at law upon or under or with respect to this Indenture or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless such Holder previously shall have given to the Trustee written notice of an Event of Default with respect to such Note and of the continuance thereof, as hereinabove provided, and unless also Noteholders of a majority in aggregate principal amount of the Notes of all series then outstanding in respect of which an Event of Default has occurred and is continuing, considered as one class, shall have made written request upon the Trustee to institute such action, suit or proceeding in its own name as Trustee hereunder and shall have offered to the Trustee such reasonable indemnity as it may require against the costs, expenses and liabilities to be incurred therein or thereby, and the Trustee for 60 days after its receipt of such notice, request and offer of indemnity, shall have neglected or refused to institute any such action, suit or proceeding; it being understood and intended, and being expressly covenanted by the taker and Holder of every Note of any series with every other taker and Holder and the Trustee, that no one or more Holders of Notes of such series shall have any right in any manner whatever by virtue or by availing of any provision of this Indenture to affect, disturb or prejudice the rights of any other Holder of Notes of such series, or to obtain or seek to obtain priority over or preference to any other such Holder or to enforce any right under this Indenture, except in the manner herein provided and for the equal, ratable and common benefit of all Holders of Notes of such series. For the protection and enforcement of the provisions of this Section, each and every Noteholder and the Trustee shall be entitled to such relief as can be given either at law or in equity.

(b) Notwithstanding any other provision in this Indenture, however, the rights of any Holder of any Note to receive payment of the principal of and any premium and interest on such Note, on or after the respective due dates expressed in such Note or on the applicable redemption date, or to institute suit for the enforcement of any such payment on or after such respective dates are absolute and unconditional, and shall not be impaired or affected without the consent of such Holder.

Section 8.05 SUITS FOR ENFORCEMENT. In case an Event of Default has occurred, has not been waived and is continuing hereunder, the Trustee may in its discretion proceed to protect and enforce the rights vested in it by this Indenture by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any of such rights, either by suit in equity or by action at law or by proceeding in bankruptcy or otherwise, whether for the specific enforcement of any covenant or agreement contained in this Indenture or in aid of the exercise of

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any power granted to it under this Indenture, or to enforce any other legal or equitable right vested in the Trustee by this Indenture or by law.

Section 8.06 POWERS AND REMEDIES CUMULATIVE; DELAY OR OMISSION NOT WAIVER OF DEFAULT. No right or remedy herein conferred upon or reserved to the Trustee or to the Holders of Notes is intended to be exclusive of any other right or remedy, and every right and remedy shall, to the extent permitted by law, be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other appropriate right or remedy.

No delay or omission of the Trustee or of any Holder of Notes to exercise any right or power accruing upon any Event of Default occurring and continuing as aforesaid shall impair any such right or power or shall be construed to be a waiver of any such Event of Default or an acquiescence therein; and, subject to
Section 8.04, every right and power given by this Indenture or by law to the Trustee or to the Holders of Notes may be exercised from time to time, and as often as shall be deemed expedient, by the Trustee or by the Holders of Notes, as the case may be.

Section 8.07 DIRECTION OF PROCEEDINGS AND WAIVER OF DEFAULTS BY MAJORITY OF NOTEHOLDERS.

(a) The Holders of a majority in aggregate principal amount of the Notes of any series at the time outstanding shall have the right to direct the time, method, and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred on the Trustee; provided, however, that if an Event of Default shall have occurred and be continuing with respect to more than one series of Notes, the Holders of a majority in aggregate principal amount of the Outstanding Notes of all such series, considered as one class, shall have the right to make such direction, and not the Holders of the Notes of any one of such series; provided, further, that such direction shall not be otherwise than in accordance with law and the provisions of this Indenture; and provided further that (subject to Section 9.01 hereof) the Trustee shall have the right to decline to follow any such direction if the Trustee being advised by counsel determines that the action or proceeding so directed may not lawfully be taken or if the Trustee in good faith by its board of directors or trustees, executive committee, or a trust committee of directors or trustees or responsible officers shall determine that the action or proceeding so directed would involve the Trustee in personal liability. Nothing in this Indenture shall impair the right of the Trustee in its discretion to take any action deemed proper by the Trustee and which is not inconsistent with such direction or directions by Noteholders.

(b) The Holders of a majority in aggregate principal amount of the Notes of any series at the time outstanding may on behalf of all of the Holders of the Notes of such series waive any past default or Event of Default hereunder and its consequences except a default in the payment of principal of or any premium or interest on the Notes of such series. Upon any such waiver the Company, the Trustee and the Holders of the Notes of such series shall be restored to their former positions and rights hereunder, respectively, but no such waiver shall extend to any subsequent or other default or Event of Default or impair any right consequent thereon. Upon

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any such waiver, such default shall cease to exist and be deemed to have been cured and not to be continuing, and any Event of Default arising therefrom shall be deemed to have been cured and not to be continuing, for every purpose of this Indenture; but no such waiver shall extend to any subsequent or other default or Event of Default or impair any right consequent thereon.

Section 8.08 NOTICE OF DEFAULT. The Trustee shall, within 90 days after the occurrence of a default with respect to the Notes of any series, give to all Holders of the Notes of such series, in the manner provided in Section 15.10, notice of such default actually known to the Trustee, unless such default shall have been cured or waived before the giving of such notice, the term "default" for the purpose of this Section 8.08 being hereby defined to be any event which is or after notice or lapse of time or both would become an Event of Default; provided that, except in the case of default in the payment of the principal of or any premium or interest on any of the Notes of such series, or in the payment of any sinking or purchase fund installments, the Trustee shall be protected in withholding such notice if and so long as its board of directors or trustees, executive committee, or a trust committee of directors or trustees or responsible officers in good faith determines that the withholding of such notice is in the interests of the Holders of the Notes of such series.

Section 8.09 UNDERTAKING TO PAY COSTS. All parties to this Indenture agree, and each Holder of any Note by acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture or in any suit against the Trustee for any action taken, suffered or omitted by it as Trustee, the filing by any party litigant in such suit of an undertaking to pay the costs of such suit, and that such court may in its discretion assess reasonable costs, including reasonable attorneys' fees, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but this Section 8.09 shall not apply to any suit instituted by the Trustee, or to any suit instituted by any Noteholder, or group of Noteholders, holding in the aggregate more than 10% in principal amount of the Notes of all series in respect of which such suit may be brought, considered as one class, or to any suit instituted by any Noteholder for the enforcement of the payment of the principal of or any premium or interest on any Note on or after the due date expressed in such Note or the applicable redemption date.

Section 8.10 RESTORATION OF RIGHTS ON ABANDONMENT OF PROCEEDINGS. In case the Trustee or any Holder shall have proceeded to enforce any right under this Indenture and such proceedings shall have been discontinued or abandoned for any reason, or shall have been determined adversely to the Trustee or to such Holder, then, and in every such case, the Company, the Trustee and the Holders shall be restored respectively to their former positions and rights hereunder, and all rights, remedies and powers of the Company, the Trustee and the Holders shall continue as though no such proceedings had been taken.

Section 8.11 WAIVER OF USURY, STAY OR EXTENSION LAWS. The Company covenants (to the extent that it may lawfully do so) that it will not at any time insist upon, or plead, or in any manner whatsoever claim or take the benefit or advantage of, any usury, stay or extension law wherever enacted, now or at any time hereafter in force, which may affect the covenants or the performance of this Indenture; and the Company (to the extent that it may lawfully do so) hereby expressly waives all benefit or advantage of any such law and covenants that it will not hinder,

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delay or impede the execution of any power herein granted to the Trustee, but will suffer and permit the execution of every such power as though no such law had been enacted.

ARTICLE IX

CONCERNING THE TRUSTEE

Section 9.01 DUTIES AND RESPONSIBILITIES OF TRUSTEE.

(a) The Trustee, prior to the occurrence of an Event of Default and after the curing of all Events of Default which may have occurred, undertakes to perform such duties and only such duties as are specifically set forth in this Indenture. If an Event of Default has occurred (which has not been cured or waived), the Trustee shall exercise such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent man would exercise or use under the circumstances in the conduct of his own affairs.

(b) No provisions of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act or its own willful misconduct, except that:

(1) prior to the occurrence of any Event of Default and after the curing or waiving of all Events of Default which may have occurred

(A) the duties and obligations of the Trustee shall be determined solely by the express provisions of this Indenture, and the Trustee shall not be liable except for the performance of such duties and obligations as are specifically set forth in this Indenture, and no implied covenants or obligations shall be read into this Indenture against the Trustee; and

(B) in the absence of bad faith or actual knowledge on the part of the Trustee, the Trustee may conclusively rely, as to the truth of the statements and the correctness of the opinions expressed therein, upon any certificates or opinions furnished to the Trustee and conforming to the requirements of this Indenture; but, in the case of any such certificates or opinions which by any provision hereof are specifically required to be furnished to the Trustee, the Trustee shall be under a duty to examine the same to determine whether or not they conform to the requirements of this Indenture (but need not confirm or investigate the accuracy of mathematical calculations or other facts stated therein);

(2) the Trustee shall not be liable for any error of judgment made in good faith by a Responsible Officer or Officers of the Trustee, unless it shall be proved that the Trustee was negligent in ascertaining the pertinent facts; and

(3) the Trustee shall not be liable with respect to any action taken or omitted to be taken by it in good faith in accordance with the direction, pursuant to this Indenture, of the Holders of a majority in aggregate principal amount of the Notes of any

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one or more series, as provided herein, including, but not limited to,
Section 8.07 hereof relating to the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred upon the Trustee under this Indenture with respect to the Notes of such series.

(c) No provision of this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur any financial liability in the performance of any of its duties hereunder, or in the exercise of any of its rights or powers, if it shall have reasonable grounds for believing that repayment of such funds or adequate indemnity against such risk or liability is not reasonably assured to it.

(d) Whether or not therein expressly so provided, every provision of this Indenture relating to the conduct or affecting the liability of or affording protection to the Trustee shall be subject to the provisions of this Section.

Section 9.02 RELIANCE ON DOCUMENTS, OPINIONS, ETC. Except as otherwise provided in Section 9.01 hereof:

(a) the Trustee may conclusively rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, note or other paper or document believed by it to be genuine and to have been signed or presented by the proper party or parties;

(b) any request, direction, order or demand of the Company mentioned herein shall be sufficiently evidenced by an Officers' Certificate (unless other evidence in respect thereof is herein specifically prescribed); and any Board Resolution may be evidenced to the Trustee by a copy thereof certified by the Secretary or an Assistant Secretary of the Company;

(c) the Trustee may consult with counsel of its selection and any advice or Opinion of Counsel shall be full and complete authorization and protection in respect of any action taken, suffered or omitted by it hereunder in good faith and in accordance with such advice or Opinion of Counsel;

(d) the Trustee shall be under no obligation to exercise any of the rights or powers vested in it by this Indenture at the request, order or direction of any of the Noteholders, pursuant to this Indenture, unless such Noteholders shall have offered to the Trustee reasonable security or indemnity against the costs, expenses and liabilities which may be incurred by such exercise;

(e) the Trustee shall not be liable for any action taken, suffered or omitted by it in good faith and believed by it to be authorized or within the discretion or rights or powers conferred upon it by this Indenture;

(f) prior to the occurrence of an Event of Default hereunder and after the curing or waiving of all Events of Default, the Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, approval, note or other paper or document, unless requested in writing to do so by the Holders of a majority in aggregate principal amount of the then

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outstanding Notes of any series; provided that if the payment within a reasonable time to the Trustee of the costs, expenses or liabilities likely to be incurred by it in the making of such investigation is, in the opinion of the Trustee, not reasonably assured to the Trustee by the security afforded to it by this Indenture, the Trustee may require reasonable indemnity against such expense or liability as a condition to so proceeding;

(g) the Trustee may execute any of the trusts or powers hereunder or perform any duties hereunder either directly or through agents or attorneys; provided that the Trustee shall not be liable for the conduct or acts of any such agent or attorney that shall have been appointed in accordance herewith with due care.

Section 9.03 NO RESPONSIBILITY FOR RECITALS, ETC. The recitals contained herein and in the Notes (except in the certificate of authentication) shall be taken as the statements of the Company, and the Trustee assumes no responsibility for the correctness of the same. The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Notes. The Trustee shall not be accountable for the use or application by the Company of any Notes or the proceeds of any Notes authenticated and delivered by the Trustee in conformity with this Indenture.

Section 9.04 TRUSTEE, AUTHENTICATING AGENT, PAYING AGENT OR REGISTRAR MAY OWN NOTES. The Trustee and any Authenticating Agent or paying agent in its individual or other capacity, may become the owner or pledgee of Notes with the same rights it would have if it were not Trustee, Authenticating Agent or paying agent.

Section 9.05 MONEYS TO BE HELD IN TRUST. Subject to Section 5.05 hereof, all moneys received by the Trustee shall, until used or applied as herein provided, be held in trust for the purposes for which they were received, but need not be segregated from other funds except to the extent required by law. The Trustee may allow and credit to the Company interest on any money received hereunder at such rate, if any, as may be agreed upon by the Company and the Trustee from time to time as may be permitted by law.

Section 9.06 COMPENSATION AND EXPENSES OF TRUSTEE. The Company covenants and agrees to pay to the Trustee from time to time, and the Trustee shall be entitled to, such compensation as the Company and the Trustee shall from time to time agree in writing (which shall not be limited by any law in regard to the compensation of a trustee of an express trust), and the Company shall pay or reimburse the Trustee upon its request for all reasonable expenses, disbursements and advances incurred or made by the Trustee in accordance with this Indenture (including the reasonable compensation and the reasonable expenses and disbursements of its counsel and agents, including any Authenticating Agents, and of all persons not regularly in its employ) except any such expense, disbursement or advance as may arise from its negligence or bad faith. The Company also covenants to indemnify each of the Trustee or any predecessor and their agents for, and to hold it harmless against, any loss, liability or expense incurred without negligence or bad faith on the part of the Trustee and arising out of or in connection with the acceptance or administration of this trust, including the costs and expenses of defending itself against any claim or liability. The obligations of the Company under this
Section 9.06 to compensate the Trustee and to pay or reimburse the Trustee for expenses, disbursements and advances shall constitute additional indebtedness hereunder. Such additional indebtedness shall

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be secured by a lien prior to that of the Notes upon all property and funds held or collected by the Trustee as such, except funds held in trust for the benefit of the Holders of any particular Notes. The provisions of this Section 9.06 shall survive termination of this Indenture.

Section 9.07 OFFICERS' CERTIFICATE AS EVIDENCE. Whenever in the administration of this Indenture, the Trustee shall deem it necessary or desirable that a matter be proved or established prior to the taking, suffering or omitting of any action hereunder, such matter (unless other evidence in respect thereof is herein specifically prescribed) may, in the absence of negligence or bad faith on the part of the Trustee, be deemed to be conclusively proved and established by an Officers' Certificate delivered to the Trustee, and such Officers' Certificate, in the absence of negligence or bad faith on the part of the Trustee, shall be full warrant to the Trustee for any action taken, suffered or omitted by it under this Indenture in reliance thereon.

Section 9.08 CONFLICTING INTEREST OF TRUSTEE. The Trustee shall be subject to and shall comply with the provisions of Section 310(b) of the TIA. Nothing in this Indenture shall be deemed to prohibit the Trustee or the Company from making any application permitted pursuant to such section.

Section 9.09 EXISTENCE AND ELIGIBILITY OF TRUSTEE. There shall at all times be a Trustee hereunder which Trustee shall at all times be a corporation organized and doing business under the laws of the United States or any State thereof or of the District of Columbia having a combined capital and surplus of at least $50,000,000 and which is authorized under such laws to exercise corporate trust powers and is subject to supervision or examination by Federal or State authorities. Such corporation shall have its principal place of business in the City of St. Louis, Missouri or the Borough of Manhattan, The City of New York, State of New York, if there be such a corporation in such location willing to act upon reasonable and customary terms and conditions. If such corporation publishes reports of condition at least annually, pursuant to law or to the requirements of the aforesaid authority, then for the purposes of this Section 9.09, the combined capital and surplus shall be deemed to be as set forth in its most recent report of condition so published. No obligor upon the Notes or Person directly or indirectly controlling, controlled by, or under common control with such obligor shall serve as Trustee. If at any time the Trustee shall cease to be eligible in accordance with this Section 9.09, the Trustee shall resign immediately in the manner and with the effect specified in
Section 9.10 hereof.

Section 9.10 RESIGNATION OR REMOVAL OF TRUSTEE.

(a) Pursuant to the provisions of this Article, the Trustee may at any time resign and be discharged of the trusts created by this Indenture by giving written notice to the Company specifying the day upon which such resignation shall take effect, and such resignation shall take effect immediately upon the later of the appointment of a successor trustee and such day.

(b) Any Trustee may be removed at any time with respect to the Notes of any series by an instrument or concurrent instruments in writing filed with such Trustee and signed and acknowledged by the Holders of a majority in aggregate principal amount of the then outstanding Notes of such series or by their attorneys in fact duly authorized.

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(c) So long as no Event of Default has occurred and is continuing, and no event has occurred and is continuing that, with the giving of notice or the lapse of time or both, would become an Event of Default, the Company may remove any Trustee upon written notice to the Holder of each Note Outstanding and the Trustee and appoint a successor Trustee meeting the requirements of
Section 9.09. The Company or the successor Trustee shall give notice to the Holders, in the manner provided in Section 15.10, of such removal and appointment within 30 days of such removal and appointment.

(d) If at any time (i) the Trustee shall cease to be eligible in accordance with Section 9.09 hereof and shall fail to resign after written request therefor by the Company or by any Holder who has been a bona fide Holder for at least six months, (ii) the Trustee shall fail to comply with Section 9.08 hereof after written request therefor by the Company or any such Holder, or
(iii) the Trustee shall become incapable of acting or shall be adjudged a bankrupt or insolvent or a receiver of the Trustee or its property shall be appointed or any public officer shall take charge or control of the Trustee or of its property or affairs for the purpose of rehabilitation, conservation or liquidation, then the Trustee may be removed forthwith by an instrument or concurrent instruments in writing filed with the Trustee and either:

(1) signed by the President or any Vice President of the Company and attested by the Secretary or an Assistant Secretary of the Company; or

(2) signed and acknowledged by the Holders of a majority in principal amount of outstanding Notes or by their attorneys in fact duly authorized.

(e) Any resignation or removal of the Trustee shall not become effective until acceptance of appointment by the successor Trustee as provided in Section 9.11 hereof.

Section 9.11 APPOINTMENT OF SUCCESSOR TRUSTEE.

(a) If at any time the Trustee shall resign or be removed, the Company, by a Board Resolution, shall promptly appoint a successor Trustee.

(b) The Company shall provide written notice of its appointment of a Successor Trustee to the Holder of each Note Outstanding following any such appointment.

(c) If no appointment of a successor Trustee shall be made pursuant to Section 9.11(a) hereof within 60 days after appointment shall be required, any Noteholder or the resigning Trustee may apply to any court of competent jurisdiction to appoint a successor Trustee. Said court may thereupon after such notice, if any, as such court may deem proper and prescribe, appoint a successor Trustee.

(d) Any Trustee appointed under this Section 9.11 as a successor Trustee shall be a bank or trust company eligible under Section 9.09 hereof and qualified under Section 9.08 hereof.

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Section 9.12 ACCEPTANCE BY SUCCESSOR TRUSTEE.

(a) Any successor Trustee appointed as provided in Section 9.11 hereof shall execute, acknowledge and deliver to the Company and to its predecessor Trustee an instrument accepting such appointment hereunder, and thereupon the resignation or removal of the predecessor Trustee shall become effective and such successor Trustee, without any further act, deed or conveyance, shall become vested with all the rights, powers, duties and obligations of its predecessor hereunder, with like effect as if originally named as Trustee herein; but nevertheless, on the written request of the Company or of the successor Trustee, the Trustee ceasing to act shall, upon payment of any amounts then due it pursuant to Section 9.06 hereof, execute and deliver an instrument transferring to such successor Trustee all the rights and powers of the Trustee so ceasing to act. Upon request of any such successor Trustee, the Company shall execute any and all instruments in writing in order more fully and certainly to vest in and confirm to such successor Trustee all such rights and powers. Any Trustee ceasing to act shall, nevertheless, retain a lien upon all property or funds held or collected by such Trustee to secure any amounts then due it pursuant to Section 9.06 hereof.

(b) No successor Trustee shall accept appointment as provided in this Section 9.12 unless at the time of such acceptance such successor Trustee shall be qualified under Section 9.08 hereof and eligible under Section 9.09 hereof.

(c) Upon acceptance of appointment by a successor Trustee as provided in this Section 9.12, the successor Trustee shall mail notice of its succession hereunder to all Holders of Notes as the names and addresses of such Holders appear on the registry books.

Section 9.13 SUCCESSION BY MERGER, ETC.

(a) Any corporation into which the Trustee may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which the Trustee shall be a party, or any corporation succeeding to all or substantially all of the corporate trust business of the Trustee, shall be the successor of the Trustee hereunder without the execution or filing of any paper or any further act on the part of any of the parties hereto, provided such corporation shall be otherwise qualified and eligible under this Article.

(b) If at the time such successor to the Trustee shall succeed to the trusts created by this Indenture any of the Notes shall have been authenticated but not delivered, any such successor to the Trustee may adopt the certificate of authentication of any predecessor Trustee, and deliver such Notes so authenticated; and in case at that time any of the Notes shall not have been authenticated, any successor to the Trustee may authenticate such Notes either in the name of any predecessor hereunder or in the name of the successor Trustee; and in all such cases such certificates shall have the full force which it is anywhere in the Notes or in this Indenture provided that the certificates of the Trustee shall have; provided that the right to adopt the certificate of authentication of any predecessor Trustee or authenticate Notes in the name of any predecessor Trustee shall apply only to its successor or successors by merger, conversion or consolidation.

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Section 9.14 LIMITATIONS ON RIGHTS OF TRUSTEE AS A CREDITOR. The Trustee shall be subject to, and shall comply with, the provisions of Section 311 of the TIA.

Section 9.15 AUTHENTICATING AGENT.

(a) There may be one or more Authenticating Agents appointed by the Trustee with the written consent of the Company, with power to act on its behalf and subject to the direction of the Trustee in the authentication and delivery of Notes in connection with transfers and exchanges under Sections 2.06, 2.07, 2.08, 2.13, 3.03, and 13.04 hereof, as fully to all intents and purposes as though such Authenticating Agents had been expressly authorized by those Sections to authenticate and deliver Notes. For all purposes of this Indenture, the authentication and delivery of Notes by any Authenticating Agent pursuant to this Section 9.15 shall be deemed to be the authentication and delivery of such Notes "by the Trustee." Any such Authenticating Agent shall be a bank or trust company or other Person of the character and qualifications set forth in Section 9.09 hereof.

(b) Any corporation into which any Authenticating Agent may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which any Authenticating Agent shall be a party, or any corporation succeeding to the corporate trust business of any Authenticating Agent, shall be the successor of such Authenticating Agent hereunder, if such successor corporation is otherwise eligible under this Section 9.15, without the execution or filing of any paper or any further act on the part of the parties hereto or such Authenticating Agent or such successor corporation.

(c) Any Authenticating Agent may at any time resign by giving written notice of resignation to the Trustee and to the Company. The Trustee may at any time terminate the agency of any Authenticating Agent by giving written notice of termination to such Authenticating Agent and to the Company. Upon receiving such a notice of resignation or upon such a termination, or in case at any time any Authenticating Agent shall cease to be eligible under this Section 9.15, the Trustee may, with the written consent of the Company, appoint a successor Authenticating Agent, and upon so doing shall give written notice of such appointment to the Company and shall mail, in the manner provided in
Section 15.10, notice of such appointment to the Holders of Notes.

(d) The Trustee agrees to pay to each Authenticating Agent from time to time reasonable compensation for its services, and the Trustee shall be entitled to be reimbursed for such payments, in accordance with Section 9.06 hereof.

(e) Sections 9.02, 9.03, 9.06, 9.07 and 9.09 hereof shall be applicable to any Authenticating Agent.

ARTICLE X

CONCERNING THE NOTEHOLDERS

Section 10.01 ACTION BY NOTEHOLDERS. Whenever in this Indenture it is provided that the Holders of a specified percentage in aggregate principal amount of the Notes of any series

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may take any action, the fact that at the time of taking any such action the Holders of such specified percentage have joined therein may be evidenced (a) by any instrument or any number of instruments of similar tenor executed by such Noteholders in person or by agent or proxy appointed in writing, (b) by the record of such Noteholders voting in favor thereof at any meeting of Noteholders duly called and held in accordance with Article XI hereof, or (c) by a combination of such instrument or instruments and any such record of such a meeting of Noteholders.

Section 10.02 PROOF OF EXECUTION BY NOTEHOLDERS.

(a) Subject to Sections 9.01, 9.02 and 11.05 hereof, proof of the execution of any instruments by a Noteholder or the agent or proxy for such Noteholder shall be sufficient if made in accordance with such reasonable rules and regulations as may be prescribed by the Trustee or in such manner as shall be satisfactory to the Trustee. The ownership of Notes shall be proved by the register for the Notes maintained by the Trustee.

(b) The record of any Noteholders' meeting shall be proven in the manner provided in Section 11.06 hereof.

Section 10.03 PERSONS DEEMED ABSOLUTE OWNERS. Subject to Sections 2.04(f) and 10.01 hereof, the Company, the Trustee, any paying agent and any Authenticating Agent shall deem the person in whose name any Note shall be registered upon the register for the Notes to be, and shall treat such person as, the absolute owner of such Note (whether or not such Note shall be overdue) for the purpose of receiving payment of or on account of the principal and premium, if any, and interest on such Note, and for all other purposes; and neither the Company nor the Trustee nor any paying agent nor any Authenticating Agent shall be affected by any notice to the contrary. All such payments shall be valid and effectual to satisfy and discharge the liability upon any such Note to the extent of the sum or sums so paid.

Section 10.04 COMPANY-OWNED NOTES DISREGARDED. In determining whether the Holders of the requisite aggregate principal amount of outstanding Notes of any series have concurred in any direction, consent or waiver under this Indenture, Notes that are owned by the Company or any other obligor on the Notes or by any person directly or indirectly controlling or controlled by or under direct or indirect common control with the Company or any other obligor on the Notes shall be disregarded and deemed not to be outstanding for the purpose of any such determination; provided that, for the purposes of determining whether the Trustee shall be protected in relying on any such direction, consent or waiver, only Notes which the Trustee knows are so owned shall be so disregarded. Notes so owned which have been pledged in good faith to third parties may be regarded as outstanding for the purposes of this Section 10.04 if the pledgee shall establish the pledgee's right to take action with respect to such Notes and that the pledgee is not a person directly or indirectly controlling or controlled by or under direct or indirect common control with the Company or any such other obligor. In the case of a dispute as to such right, the Trustee may rely upon an Opinion of Counsel and an Officers' Certificate to establish the foregoing.

Section 10.05 REVOCATION OF CONSENTS; FUTURE HOLDERS BOUND. Except as may be otherwise required in the case of a Global Note by the applicable rules and regulations of the

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Depositary, at any time prior to the taking of any action by the Holders of the percentage in aggregate principal amount of the Notes of any series specified in this Indenture in connection with such action, any Holder of a Note, which has been included in the Notes the Holders of which have consented to such action may, by filing written notice with the Trustee at the corporate trust office of the Trustee and upon proof of ownership as provided in Section 10.02(a) hereof, revoke such action so far as it concerns such Note. Except as aforesaid, any such action taken by the Holder of any Note shall be conclusive and binding upon such Holder and upon all future Holders and owners of such Note and of any Notes issued in exchange, substitution or upon registration of transfer therefor, irrespective of whether or not any notation thereof is made upon such Note or such other Notes.

Section 10.06 RECORD DATE FOR NOTEHOLDER ACTS. If the Company shall solicit from the Noteholders any request, demand, authorization, direction, notice, consent, waiver or other act, the Company may, at its option, by Board Resolution, fix in advance a record date for the determination of Noteholders entitled to give such request, demand, authorization, direction, notice, consent, waiver or other act, but the Company shall have no obligation to do so. If such a record date is fixed, such request, demand, authorization, direction, notice, consent, waiver or other act may be given before or after the record date, but only the Noteholders of record at the close of business on the record date shall be deemed to be Noteholders for the purpose of determining whether Holders of the requisite aggregate principal amount of outstanding Notes have authorized or agreed or consented to such request, demand, authorization, direction, notice, consent, waiver or other act, and for that purpose the outstanding Notes shall be computed as of the record date; provided that no such request, demand, authorization, direction, notice, consent, waiver or other act by the Noteholders on the record date shall be deemed effective unless it shall become effective pursuant to this Indenture not later than six months after the record date. Any such record date shall be at least 30 days prior to the date of the solicitation to the Noteholders by the Company.

ARTICLE XI

NOTEHOLDERS' MEETING

Section 11.01 PURPOSES OF MEETINGS. A meeting of Noteholders may be called at any time and from time to time pursuant to this Article XI for any of the following purposes:

(a) to give any notice to the Company or to the Trustee, or to give any directions to the Trustee, or to consent to the waiving of any Event of Default hereunder and its consequences, or to take any other action authorized to be taken by Noteholders pursuant to Article XIII;

(b) to remove the Trustee pursuant to Article IX;

(c) to consent to the execution of an indenture or indentures supplemental hereto pursuant to Section 13.02 hereof; or

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(d) to take any other action authorized to be taken by or on behalf of the Holders of any specified aggregate principal amount of the Notes of any series, as the case may be, under any other provision of this Indenture or under applicable law.

Section 11.02 CALL OF MEETINGS BY TRUSTEE. The Trustee may at any time call a meeting of Holders of Notes to take any action specified in Section 11.01 hereof, to be held at such time and at such place as the Trustee shall determine. Notice of every such meeting of Noteholders, setting forth the time and the place of such meeting and in general terms the action proposed to be taken at such meeting, shall be given to Holders of the Notes that may be affected by the action proposed to be taken at such meeting in the manner provided in Section 15.10 hereof. Such notice shall be given not less than 20 nor more than 90 days prior to the date fixed for such meeting.

Section 11.03 CALL OF MEETINGS BY COMPANY OR NOTEHOLDERS. If at any time the Company, pursuant to a Board Resolution, or the Holders of at least 10% in aggregate principal amount of the Notes of all series then outstanding, considered as one class, shall have requested the Trustee to call a meeting of Noteholders, by written request setting forth in reasonable detail the action proposed to be taken at the meeting, and the Trustee shall not have mailed the notice of such meeting within 20 days after receipt of such request, then the Company or such Noteholders may determine the time and the place for such meeting and may call such meeting to take any action authorized in Section 11.01 hereof, by giving notice thereof as provided in Section 11.02 hereof.

Section 11.04 QUALIFICATIONS FOR VOTING. To be entitled to vote at any meetings of Noteholders a Person shall (a) be a Holder of one or more Notes affected by the action proposed to be taken or (b) be a Person appointed by an instrument in writing as proxy by a Holder of one or more such Notes. The only Persons who shall be entitled to be present or to speak at any meeting of Noteholders shall be the Persons entitled to vote at such meeting and their counsel and any representatives (including employees) of the Trustee and its counsel and any representatives (including employees) of the Company and its counsel.

Section 11.05 REGULATIONS.

(a) Notwithstanding any other provisions of this Indenture, the Trustee may make such reasonable regulations as it may deem advisable for any meeting of Noteholders in regard to proof of the holding of Notes and of the appointment of proxies, and in regard to the appointment and duties of inspectors of votes, the submission and examination of proxies, certificates and other evidence of the right to vote, and such other matters concerning the conduct of the meeting as it shall think fit.

(b) The Trustee shall, by an instrument in writing, appoint a temporary chairman of the meeting, unless the meeting shall have been called by the Company or by the Noteholders as provided in Section 11.03 hereof, in which case the Company or Noteholders calling the meeting, as the case may be, shall in like manner appoint a temporary chairman. A permanent chairman and a permanent secretary of the meeting shall be elected by the Holders of a majority in aggregate principal amount of the Notes present in person or by proxy at the meeting.

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(c) Subject to Section 10.04 hereof, at any meeting each Noteholder or proxy shall be entitled to one vote for each $1,000 principal amount of Notes held or represented by such Noteholder; provided that no vote shall be cast or counted at any meeting in respect of any Note determined to be not outstanding. The chairman of the meeting shall have no right to vote other than by virtue of Notes held by such chairman or instruments in writing as aforesaid duly designating such chairman as the person to vote on behalf of other Noteholders. At any meeting of Noteholders duly called pursuant to Section 11.02 or 11.03 hereof, the presence of persons holding or representing Notes in an aggregate principal amount sufficient to take action on any business for the transaction for which such meeting was called shall constitute a quorum. Any meeting of Noteholders duly called pursuant to Section 11.02 or 11.03 hereof may be adjourned from time to time by the Holders of a majority in aggregate principal amount of the Notes present in person or by proxy at the meeting, whether or not constituting a quorum, and the meeting may be held as so adjourned without further notice.

Section 11.06 VOTING. The vote upon any resolution submitted to any meeting of Noteholders shall be by written ballots on which shall be subscribed the signatures of the Holders of Notes or of their representatives by proxy and the principal amount of Notes held or represented by them. The permanent chairman of the meeting shall appoint two inspectors of votes who shall count all votes cast at the meeting for or against any resolution and who shall make and file with the secretary of the meeting their verified written reports in duplicate of all votes cast at the meeting. A record in duplicate of the proceedings of such meeting of Noteholders shall be prepared by the secretary of the meeting and there shall be attached to said record the original reports of the inspectors of votes on any vote by ballot taken thereat and affidavits by one or more persons having knowledge of the facts setting forth a copy of the notice of the meeting and showing that said notice was given as provided in
Section 11.02 hereof. The record shall show the aggregate principal amount of the Notes voting in favor of or against any resolution. The record shall be signed and verified by the affidavits of the permanent chairman and secretary of the meeting and one of the duplicates shall be delivered to the Company and the other to the Trustee to be preserved by the Trustee and the Trustee shall have the ballots taken at the meeting attached to such duplicate. Any record so signed and verified shall be conclusive evidence of the matters therein stated.

Section 11.07 RIGHTS OF TRUSTEE OR NOTEHOLDERS NOT DELAYED. Nothing in this Article XI shall be deemed or construed to authorize or permit, by reason of any call of a meeting of Noteholders or any rights expressly or impliedly conferred hereunder to make such call, any hindrance or delay in the exercise of any right or rights conferred upon or reserved to the Trustee or to the Holders of Notes under any of the provisions of this Indenture or of the Notes.

ARTICLE XII

CONSOLIDATION, MERGER, SALE, TRANSFER OR CONVEYANCE

Section 12.01 COMPANY MAY CONSOLIDATE, ETC. ONLY ON CERTAIN TERMS. The Company shall not consolidate with or merge into any other corporation or sell or otherwise dispose of its properties as or substantially as an entirety to any Person unless the Company has delivered to the Trustee an Officers' Certificate and an Opinion of Counsel each stating that such consolidation, merger, conveyance or transfer and the supplemental indenture referred to in

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clause (b) below comply with this Article XII and that all conditions precedent herein provided for have been complied with, and the corporation formed by such consolidation or into which the Company is merged or the Person which receives such properties pursuant to such sale, transfer or other disposition (a) shall be a corporation organized and existing under the laws of the United States of America, any state thereof or the District of Columbia; and (b) shall expressly assume, by an indenture supplemental hereto, executed and delivered to the Trustee, in form reasonably satisfactory to the Trustee, the due and punctual payment of the principal of and premium and interest on all of the Notes and the performance of every covenant of this Indenture on the part of the Company to be performed or observed.

Section 12.02 SUCCESSOR CORPORATION SUBSTITUTED. Upon any consolidation or merger, or any sale, transfer or other disposition of the properties of the Company substantially as an entirety in accordance with Section 12.01 hereof, the successor corporation formed by such consolidation or into which the Company is merged or the Person to which such sale, transfer or other disposition is made shall succeed to, and be substituted for and may exercise every right and power of, the Company under this Indenture with the same effect as if such successor corporation or Person had been named as the Company herein and the Company shall be released from all obligations hereunder.

ARTICLE XIII

SUPPLEMENTAL INDENTURES

Section 13.01 SUPPLEMENTAL INDENTURES WITHOUT CONSENT OF NOTEHOLDERS.

(a) The Company, when authorized by Board Resolution, and the Trustee may from time to time and at any time enter into an indenture or indentures supplemental hereto for one or more of the following purposes:

(1) to make such provision in regard to matters or questions arising under this Indenture as may be necessary or desirable, and not inconsistent with this Indenture or prejudicial to the interests of the Holders in any material respect, for the purpose of supplying any omission, curing any ambiguity, or curing, correcting or supplementing any defective or inconsistent provision;

(2) to change or eliminate any of the provisions of this Indenture, provided that any such change or elimination shall become effective only when there is no Note outstanding created prior to the execution of such supplemental indenture which is entitled to the benefit of such provision or such change or elimination is applicable only to Notes issued after the effective date of such change or elimination;

(3) to establish the form of Notes of any series as permitted by Section 2.01 hereof or to establish or reflect any terms of any Note of any series determined pursuant to Section 2.05 hereof;

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(4) to evidence the succession of another corporation to the Company as permitted hereunder, and the assumption by any such successor of the covenants of the Company herein and in the Notes;

(5) to grant to or confer upon the Trustee for the benefit of the Holders any additional rights, remedies, powers or authority;

(6) to permit the Trustee to comply with any duties imposed upon it by law;

(7) to specify further the duties and responsibilities of, and to define further the relationships among, the Trustee, any Authenticating Agent and any paying agent, and to evidence the succession of a successor Trustee as permitted hereunder;

(8) to add to the covenants of the Company for the benefit of the Holders of one or more series of Notes, to add to the security for all of the Notes, to surrender a right or power conferred on the Company herein or to add any Event of Default with respect to one or more series of Notes; and

(9) to make any other change that is not prejudicial to the Holders.

(b) The Trustee is hereby authorized to join with the Company in the execution of any such supplemental indenture, to make any further appropriate agreements and stipulations which may be therein contained and to accept the conveyance, transfer and assignment of any property thereunder, but the Trustee shall not be obligated to enter into any such supplemental indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

(c) Any supplemental indenture authorized by this Section 13.01 may be executed by the Company and the Trustee without the consent of the Holders of any of the Notes at the time outstanding, notwithstanding any of the provisions of Section 13.02 hereof.

Section 13.02 SUPPLEMENTAL INDENTURES WITH CONSENT OF NOTEHOLDERS.

(a) With the consent (evidenced as provided in Section 10.01 hereof) of the Holders of a majority in aggregate principal amount of the Notes of all series at the time outstanding, considered as one class, the Company, when authorized by Board Resolution, and the Trustee may from time to time and at any time enter into an indenture or indentures supplemental hereto for the purpose of adding any provisions to, or changing in any manner or eliminating any of the provisions of, this Indenture or of any supplemental indenture or of modifying or waiving in any manner the rights of the Noteholders; provided, however, that if there shall be Notes of more than one series Outstanding hereunder and if a proposed supplemental indenture shall directly affect the rights of the Holders of Notes of one or more, but less than all, of such series, then the consent only of the Holders of a majority in aggregate principal amount of the Outstanding Notes of all series so directly affected, considered as one class, shall be required; provided further that no such supplemental indenture shall:

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(1) change the Stated Maturity of any Note, or reduce the rate (or change the method of calculation thereof) or extend the time of payment of interest thereon, or reduce the principal amount thereof or any premium thereon, or change the coin or currency in which the principal of any Note or any premium or interest thereon is payable, or change the date on which any Note may be redeemed or adversely affect the rights of the Noteholders to institute suit for the enforcement of any payment of principal of or any premium or interest on any Note, in each case without the consent of the Holder of each Note so affected; or

(2) modify this Section 13.02(a) or reduce the aforesaid percentage of Notes, the Holders of which are required to consent to any such supplemental indenture or to reduce the percentage of Notes, the Holders of which are required to waive Events of Default, in each case, without the consent of the Holders of all of the Notes affected thereby then outstanding.

(b) Upon the request of the Company, accompanied by a copy of the Board Resolution authorizing the execution of any such supplemental indenture, and upon the filing with the Trustee of evidence of the consent of Noteholders as aforesaid, the Trustee shall join with the Company in the execution of such supplemental indenture unless such supplemental indenture affects the Trustee's own rights, duties or immunities under this Indenture or otherwise, in which case the Trustee may in its discretion, but shall not be obligated to, enter into such supplemental indenture.

(c) A supplemental indenture which changes, waives or eliminates any covenant or other provision of this Indenture (or any supplemental indenture) which has expressly been included solely for the benefit of one or more series of Notes, or which modifies the rights of the Holders of Notes of such series with respect to such covenant or provision, shall be deemed not to affect the rights under this Indenture of the Holders of Notes of any other series.

(d) It shall not be necessary for the consent of the Holders of Notes under this Section 13.02 to approve the particular form of any proposed supplemental indenture, but it shall be sufficient if such consent shall approve the substance thereof.

(e) Promptly after the execution by the Company and the Trustee of any supplemental indenture pursuant to this Section 13.02, the Trustee shall give notice in the manner provided in Section 15.10 hereof, setting forth in general terms the substance of such supplemental indenture, to all Noteholders. Any failure of the Trustee to give such notice or any defect therein shall not, however, in any way impair or affect the validity of any such supplemental indenture.

Section 13.03 COMPLIANCE WITH TRUST INDENTURE ACT; EFFECT OF SUPPLEMENTAL INDENTURES. Any supplemental indenture executed pursuant to this Article XIII shall comply with the TIA. Upon the execution of any supplemental indenture pursuant to this Article XIII, the Indenture shall be and be deemed to be modified and amended in accordance therewith and the respective rights, limitations of rights, obligations, duties and immunities under this Indenture of the Trustee, the Company and the Noteholders shall thereafter be determined, exercised and enforced hereunder subject in all respects to such modifications and amendments, and all the

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terms and conditions of any such supplemental indenture shall be and be deemed to be part of the terms and conditions of this Indenture for any and all purposes.

Section 13.04 NOTATION ON NOTES. Notes of any series authenticated and delivered after the execution of any supplemental indenture pursuant to this Article XIII may bear a notation in form approved by the Trustee as to any matter provided for in such supplemental indenture. If the Company shall so determine, new Notes of any series so modified as approved by the Trustee and the Board of Directors with respect to any modification of this Indenture contained in any such supplemental indenture may be prepared and executed by the Company, authenticated by the Trustee and delivered in exchange for the Notes of such series then outstanding.

Section 13.05 EVIDENCE OF COMPLIANCE OF SUPPLEMENTAL INDENTURE TO BE FURNISHED TRUSTEE. The Trustee, subject to Sections 9.01 and 9.02 hereof, may receive an Officers' Certificate and an Opinion of Counsel as conclusive evidence that any supplemental indenture executed pursuant hereto complies with the requirements of this Article XIII.

ARTICLE XIV

IMMUNITY OF INCORPORATORS,
STOCKHOLDERS, OFFICERS AND DIRECTORS

Section 14.01 INDENTURE AND NOTES SOLELY CORPORATE OBLIGATIONS. No recourse for the payment of the principal of or any premium or interest on any Note, or for any claim based thereon or otherwise in respect thereof, and no recourse under or upon any obligation, covenant or agreement of the Company, contained in this Indenture, or in any supplemental indenture, or in any Note, or because of the creation of any indebtedness represented thereby, shall be had against any incorporator, stockholder, officer or director, as such, past, present or future, of the Company or of any successor corporation, either directly or through the Company or any successor corporation, whether by virtue of any constitution, statute or rule of law, or by the enforcement of any assessment or penalty or otherwise; it being expressly understood that all such liability is hereby expressly waived and released as a condition of, and as a consideration for, the execution of this Indenture and the issuance of the Notes.

ARTICLE XV

MISCELLANEOUS PROVISIONS

Section 15.01 PROVISIONS BINDING ON COMPANY'S SUCCESSORS. All the covenants, stipulations, promises and agreements made by the Company in this Indenture shall bind its successors and assigns whether so expressed or not.

Section 15.02 OFFICIAL ACTS BY SUCCESSOR CORPORATION. Any act or proceeding by any provision of this Indenture authorized or required to be done or performed by any board, committee or officer of the Company shall and may be done and performed with like force and effect by the like board, committee or officer of any corporation that shall at the time be the lawful successor of the Company.

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Section 15.03 NOTICES. Any notice or demand which by any provision of this Indenture is required or permitted to be given or served by the Trustee or by the Noteholders on the Company may be given or served by being deposited postage prepaid in a post office letter box addressed (until another address is filed by the Company with the Trustee) at the Principal Executive Offices of the Company, to the attention of the Secretary. Any notice, direction, request or demand by any Noteholder or the Company to or upon the Trustee shall be deemed to have been sufficiently given or made, for all purposes, if given or made in writing at the corporate trust office of the Trustee, Attention: Corporate Trust Administration.

Section 15.04 GOVERNING LAW. This Indenture and each Note shall be governed by and deemed to be a contract under, and construed in accordance with, the laws of the State of New York, and for all purposes shall be construed in accordance with the laws of said State without regard to conflicts of law principles thereof.

Section 15.05 EVIDENCE OF COMPLIANCE WITH CONDITIONS PRECEDENT.

(a) Upon any application or demand by the Company to the Trustee to take any action under this Indenture, the Company shall furnish to the Trustee an Officers' Certificate stating that all conditions precedent, if any, provided for in this Indenture (including any covenants compliance with which constitutes a condition precedent) relating to the proposed action have been complied with and an Opinion of Counsel stating that, in the opinion of such counsel, all such conditions precedent have been complied with.

(b) Each certificate or opinion provided for in this Indenture and delivered to the Trustee with respect to compliance with a condition or covenant provided for in this Indenture (other than the certificates delivered pursuant to Section 6.06 hereof) shall include (1) a statement that each Person making such certificate or opinion has read such covenant or condition and the definitions relating thereto; (2) a brief statement as to the nature and scope of the examination or investigation upon which the statements or opinions contained in such certificate or opinion are based; (3) a statement that, in the opinion of each such Person, such Person has made such examination or investigation as is necessary to enable such Person to express an informed opinion as to whether or not such covenant or condition has been complied with; and (4) a statement as to whether or not, in the opinion of each such Person, such condition or covenant has been complied with.

(c) In any case where several matters are required to be certified by, or covered by an opinion of, any specified Person, it is not necessary that all such matters be certified by, or covered by the opinion of, only one such Person, or that they be so certified or covered by only one document, but one such Person may certify or give an opinion with respect to some matters and one or more other such Persons as to other matters, and any such Person may certify or give an opinion as to such matters in one or several documents.

(d) Any certificate or opinion of an officer of the Company may be based, insofar as it relates to legal matters, upon a certificate or opinion of, or representations by, counsel, unless such officer knows, or in the exercise of reasonable care should know, that the certificate or opinion or representations with respect to the matters upon which such certificate or opinion is based are erroneous. Any such certificate or opinion of counsel delivered under the

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Indenture may be based, insofar as it relates to factual matters, upon a certificate or opinion of, or representations by, an officer or officers of the Company stating that the information with respect to such factual matters is in the possession of the Company, unless such person knows, or in the exercise of reasonable care should know, that the certificate or opinion of representations with respect to such matters are erroneous. Any opinion of counsel delivered hereunder may contain standard exceptions and qualifications reasonably satisfactory to the Trustee.

(e) Any certificate, statement or opinion of any officer of the Company, or of counsel, may be based, insofar as it relates to accounting matters, upon a certificate or opinion of or representations by an independent public accountant or firm of accountants, unless such officer or counsel, as the case may be, knows that the certificate or opinions or representations with respect to the accounting matters upon which the certificate, statement or opinion of such officer or counsel may be based as aforesaid are erroneous, or in the exercise of reasonable care should know that the same are erroneous. Any certificate or opinion of any firm of independent public accountants filed with the Trustee shall contain a statement that such firm is independent.

(f) Where any Person is required to make, give or execute two or more applications, requests, consents, certificates, statements, opinions or other instruments under this Indenture, they may, but need not, be consolidated and form one instrument.

Section 15.06 BUSINESS DAYS. Unless otherwise provided pursuant to Section 2.05(c) hereof, in any case where the date of Maturity of the principal of or any premium or interest on any Note or the date fixed for redemption of any Note is not a Business Day, then payment of such principal or any premium or interest need not be made on such date but may be made on the next succeeding Business Day with the same force and effect as if made on the date of Maturity or the date fixed for redemption, and, in the case of timely payment thereof, no interest shall accrue for the period from and after such Interest Payment Date or the date on which the principal or premium of the Note is required to be paid.

Section 15.07 TRUST INDENTURE ACT TO CONTROL. If and to the extent that any provision of this Indenture limits, qualifies or conflicts with the duties imposed by the TIA, such required provision of the TIA shall govern.

Section 15.08 TABLE OF CONTENTS, HEADINGS, ETC. The table of contents and the titles and headings of the articles and sections of this Indenture have been inserted for convenience of reference only, are not to be considered a part hereof, and shall in no way modify or restrict any of the terms or provisions hereof.

Section 15.09 EXECUTION IN COUNTERPARTS. This Indenture may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument.

Section 15.10 MANNER OF MAILING NOTICE TO NOTEHOLDERS.

(a) Any notice or demand which by any provision of this Indenture is required or permitted to be given or served by the Trustee or the Company to or on the Holders of Notes, as the case may be, shall be given or served by first-class mail, postage prepaid, addressed to the Holders of such Notes at their last addresses as the same appear on the register for the Notes

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referred to in Section 2.06, and any such notice shall be deemed to be given or served by being deposited in a post office letter box in the form and manner provided in this Section 15.10. In case by reason of the suspension of regular mail service or by reason of any other cause it shall be impracticable to give notice to any Holder by mail, then such notification to such Holder as shall be made with the approval of the Trustee shall constitute a sufficient notification for every purpose hereunder.

(b) The Company shall also provide any notices required under this Indenture by publication, but only to the extent that such publication is required by the TIA, the rules and regulations of the Commission or any securities exchange upon which any series of Notes is listed.

Section 15.11 APPROVAL BY TRUSTEE OF COUNSEL. Wherever the Trustee is required to approve counsel who is to furnish evidence of compliance with conditions precedent in this Indenture, such approval by the Trustee shall be deemed to have been given upon the taking of any action by the Trustee pursuant to and in accordance with the certificate or opinion so furnished by such counsel.

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IN WITNESS WHEREOF, AMEREN CORPORATION has caused this Indenture to be signed and acknowledged by its vice president, and attested by its assistant secretary, and THE BANK OF NEW YORK has caused this Indenture to be signed and acknowledged by its Vice President, as of the day and year first written above.

AMEREN CORPORATION

                                    By  /s/ Jerre E. Birdsong
                                       _______________________________________
                                        Vice President and Treasurer


ATTEST:

/s/ Ronald K. Evans
--------------------------------
Assistant Secretary

THE BANK OF NEW YORK,
AS TRUSTEE

By  /s/ Robert A. Massimillo
   _______________________________________
    Vice President


EXHIBIT 4.6

COMPANY ORDER

December 12, 2001

The Bank of New York
c/o BNY Trust Company of Missouri
911 Washington Street
St. Louis, Missouri 63101

Ladies and Gentlemen:

Application is hereby made to The Bank of New York, a New York banking corporation, as trustee (the "Trustee"), under the Indenture dated as of December 1, 2001 (the "Indenture"), between Ameren Corporation, a Missouri corporation (the "Company"), and the Trustee for the authentication and delivery of $150,000,000 aggregate principal amount of the Company's Floating Rate Notes due December 12, 2003 (the "Notes"), pursuant to the provisions of Article II of the Indenture. Additional Notes without limitation as to amount, and without the consent of the holders of the then Outstanding Notes, may also be authenticated and delivered in the manner provided in Section 2.05 of the Indenture. All capitalized terms not defined herein that are defined in the Indenture shall have the same meaning as used in the Indenture.

The Notes will be initially issued pursuant to Section 4(2) of the Securities Act of 1933, as amended (the "Securities Act"), in the form of Global Notes registered in the name of Cede & Co. (as nominee for The Depository Trust Company ("DTC"), New York, New York, which will act as the Depositary for the Global Notes). Pursuant to Section 2.05(c) of the Indenture, the Notes will have the terms set forth in the form of Global Note attached hereto as Exhibit A and in the form of definitive Note attached hereto as Exhibit B (which terms are incorporated by reference in this Company Order). The Global Notes shall bear the depository legend in substantially the form set forth in Exhibit A attached hereto. The Notes shall be subject to restrictions on transfer, and each Note, whether in global form or in definitive form, shall bear the non-registration legend set forth in substantially the form in the applicable form of Note, unless otherwise agreed by the Company, such agreement to be confirmed in writing to the Trustee. Nothing in the Indenture or the Notes shall be construed to require the Company to register any of the Notes under the Securities Act, unless otherwise expressly agreed by the Company, confirmed in writing to the Trustee, or to make any transfer of the Notes or the beneficial interests therein in violation of applicable law. The Notes will be issued only in denominations of $100,000 and in integral multiples of $10,000 in excess thereof.

It is contemplated that beneficial interests in the Notes owned by qualified institutional buyers (as defined in Rule 144A under the Securities Act) ("QIBs") or sold to QIBs in reliance upon Rule 144A under the Securities Act will be represented by one or more separate Global Notes (each, a "Rule 144A Global Certificate") registered in the name of Cede & Co., as registered owner and as nominee for DTC; beneficial interests in the Notes sold to purchasers pursuant to Regulation S under the Securities Act will be evidenced by one or more separate Global Notes (each, a "Regulation S Global Certificate") and will be registered in the name of


Cede & Co., as registered owner and as nominee for DTC for the accounts of The Euroclear System or Clearstream Banking, Luxembourg, societe anonyme; prior to the 40th day after the date of initial issuance of the Notes, beneficial interests in a Regulation S Global Certificate may be held only through The Euroclear System or Clearstream Banking, Luxembourg, societe anonyme (unless a resale or transfer is effected pursuant to Rule 144A under the Securities Act); Notes acquired by Institutional Accredited Investors (as defined in Rule
501(a)(1), (2), (3) or (7) under the Securities Act) ("IAIs"), who are not QIBs and who are not purchasers pursuant to Regulation S under the Securities Act, will be in definitive form. The Trustee and the Company will have no responsibility or liability for any aspect of transfers of beneficial interests in the Notes (which transfers will be conducted pursuant to the customary procedures of DTC), any records of DTC of beneficial interests or any transactions between DTC and its participants or between any such participants and any other beneficial owners or for monitoring, supervising or reviewing of any thereof.

In connection with any transfer of Notes, the Trustee and the Company shall be under no duty to inquire into, may conclusively presume the correctness of, and shall be fully protected in relying upon the certificates and other information (set forth in the form of definitive Note attached hereto as Exhibit B, for use in connection with the transfer of the Notes in definitive form, or set forth in Exhibit A-1 attached hereto, for use in connection with the transfer of beneficial interests between a Rule 144A Global Certificate and a Regulation S Global Certificate or to a Note in definitive form, or otherwise) received from the Holders and any transferees of any Notes regarding the validity, legality and due authorization of any such transfer, the eligibility of the transferee to receive such Note and any other facts and circumstances related to such transfer. Transfers of beneficial interests between a Rule 144A Global Certificate and a Regulation S Global Certificate, and other transfers relating to beneficial interests in the Notes in global form, shall be reflected by endorsements of the Trustee, as custodian for DTC, on the schedule attached to such certificate.

In connection with this Company Order, there are delivered to you herewith the following:

1. Certified copies of the resolutions adopted by the Board of Directors of the Company and by the Executive Committee of the Board of Directors of the Company authorizing this Company Order and the issuance and sale of the Notes by the Company pursuant to Section 2.05(c)(1) of the Indenture;

2. Opinions of Counsel addressed to you or in which it is stated that you may rely pursuant to Section 2.05(c)(2) of the Indenture;

3. Officers' Certificate pursuant to Section 2.05(c)(3) of the Indenture; and

4. Two Global Notes representing the Notes executed on behalf of the Company in accordance with the terms of Section 2.05(a) of the Indenture.

You are hereby instructed to authenticate the Global Notes representing the Notes and hold them as DTC's custodian. The Global Notes representing the Notes are to be held for delivery through the facilities of DTC to the initial purchasers thereof against payment therefor at

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the closing in respect of the sale thereof, such closing to be held at 10:00
a.m., New York time, December 12, 2001, at the offices of Pillsbury Winthrop LLP, One Battery Park Plaza, New York, NY 10004.

Please acknowledge receipt of the Global Notes representing the Notes, the instructions referred to above and the supporting documentation pursuant to the Indenture referred to above.

Very truly yours,

Ameren Corporation

By:  /s/ Jerre E. Birdsong
   ---------------------------
   Name:  Jerre E. Birdsong
   Title: Vice President and Treasurer

Receipt from the Company of the Global Notes representing the Notes, certain instructions related thereto and the supporting documentation pursuant to the Indenture in connection with the authentication and delivery of the Notes is hereby acknowledged.

The Bank of New York, as Trustee

By:  /s/ Robert A. Massimillo
   ------------------------------
   Name:  Robert A. Massimillo
   Title: Vice President

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EXHIBIT A

FORM OF GLOBAL NOTE

THIS NOTE IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY (REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY AS PROVIDED IN THE INDENTURE REFERRED TO BELOW, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY. UNLESS THIS NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK), TO THE TRUSTEE FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS MADE TO CEDE & CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"). THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED PRIOR TO THE DATE WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUANCE DATE THEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE THEREOF WAS THE OWNER OF THIS SECURITY OR THE EXPIRATION OF SUCH SHORTER PERIOD AS MAY BE PRESCRIBED BY RULE 144(k), OR ANY SUCCESSOR PROVISION THEREOF, UNDER THE SECURITIES ACT (THE "RESALE RESTRICTION TERMINATION DATE") OTHER THAN (1) TO THE COMPANY, (2) IN A TRANSACTION ENTITLED TO AN EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT,
(3) SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE RESALE, PLEDGE OR OTHER TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (4) IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE SECURITIES ACT, (5) TO AN INSTITUTION THAT IS AN "ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS ACQUIRING THIS SECURITY FOR INVESTMENT PURPOSES AND NOT FOR DISTRIBUTION, AND A CERTIFICATE IN THE FORM ATTACHED TO THIS SECURITY IS DELIVERED BY THE TRANSFEREE TO

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THE COMPANY AND THE TRUSTEE OR (6) IN ACCORDANCE WITH ANOTHER APPLICABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT OR PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT, IN EACH CASE IN ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES. THE FOREGOING RESTRICTIONS ON RESALE WILL NOT APPLY SUBSEQUENT TO THE RESALE RESTRICTION TERMINATION DATE.

AMEREN CORPORATION
FLOATING RATE NOTE DUE DECEMBER 12, 2003

CUSIP/ISIN:                                  NUMBER:

ORIGINAL ISSUE DATE: December 12, 2001       PRINCIPAL AMOUNT: Listed on
                                                               Schedule I hereto

INTEREST RATE: Floating, as set forth below  MATURITY DATE: December 12, 2003

AMEREN CORPORATION, a corporation of the State of Missouri (the "COMPANY"), for value received hereby promises to pay to CEDE & CO. or registered assigns, the principal amount specified above on the Maturity Date set forth above, and to pay interest thereon from and including the Original Issue Date specified above or from and including the most recent Interest Payment Date to which interest has been paid or duly provided for, quarterly in arrears on the March 12, June 12, September 12 and December 12 in each year, commencing March 12, 2002, and on the Maturity Date, at the per annum Interest Rate determined by the Calculation Agent on each Interest Determination Date, as such terms are defined herein, until the principal hereof is paid or made available for payment. No interest shall accrue on the Maturity Date, so long as the principal amount of this Note is paid on the Maturity Date. The interest so payable and punctually paid or duly provided for on any such Interest Payment Date (except for interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration) will, as provided in the Indenture (as defined below), be paid to the Person in whose name this Note is registered at the close of business on the Regular Record Date for such interest, which shall be the fifteenth calendar day next preceding such Interest Payment Date; provided, that the first Interest Payment Date for any part of this Note, the Original Issue Date of which is after a Regular Record Date but prior to the applicable Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date; and provided, that interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration, shall be payable to the Person to whom principal shall be payable. Except as otherwise provided in the Indenture, any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and shall be paid to the Person in whose name this Note is registered at the close of business on a Special Record Date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Noteholders not more than fifteen days or fewer than ten days prior to such Special Record Date. Payment of the principal of and interest and premium on this shall be payable pursuant to Section 2.12(a) of the Indenture.

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This Note is a Global Note in respect of a duly authorized issue of Floating Rate Notes due December 12, 2003 (the "NOTES OF THIS SERIES", which term includes any Global Notes representing such Notes) of the Company issued and to be issued under an Indenture dated as of December 1, 2001 between the Company and The Bank of New York, as trustee (herein called the "TRUSTEE", which term includes any successor Trustee under the Indenture) and indentures supplemental thereto (collectively, the "INDENTURE"). Under the Indenture, one or more series of notes may be issued and, as used herein, the term "Notes" refers to the Notes of this Series. Reference is hereby made to the Indenture for a more complete statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Noteholders and of the terms upon which the Notes are and are to be authenticated and delivered. This Note has been issued in respect of the series designated on the first page hereof, issued in the initial aggregate principal amount of $150,000,000.

Each Note of this Series shall be dated and issued as of the date of its authentication by the Trustee and shall bear an Original Issue Date. Each Note of this Series issued upon transfer, exchange or substitution of such Note shall bear the Original Issue Date of such transferred, exchanged or substituted Note, as the case may be.

This Note will bear interest for each Interest Period at a per annum rate ("Interest Rate") determined by The Bank of New York, or its successor appointed by the Company acting as calculation agent (the "Calculation Agent"), subject to the maximum interest rate permitted by New York or other applicable state law, as such law may be modified by United States law of general application. The Interest Rate for each Interest Period will be equal to three month LIBOR on the Interest Determination Date for such Interest Period plus 0.95%. Promptly upon such determination, the Calculation Agent will notify the Trustee for the Notes, if the Trustee is not then serving as the Calculation Agent, of the Interest Rate for the new Interest Period. The Interest Rate determined by the Calculation Agent, absent willful default, bad faith or manifest error, shall be binding and conclusive upon the beneficial owners and holders of this Note, the Company and the Trustee.

Interest on this Note will accrue from and including the Original Issue Date specified above to, but excluding, March 12, 2002, and thereafter, from and including each Interest Payment Date to, but excluding, the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

If the following circumstances exist on any Interest Determination Date, the Calculation Agent shall determine LIBOR for the Notes as follows:

(1) In the event no Reported Rate appears on Telerate Page 3750 as of approximately 11:00 a.m. London time on an Interest Determination Date, the Calculation Agent shall request the principal London offices of each of four major banks in the London interbank market selected by the Calculation Agent (after consultation with the Company) to provide a quotation of the rate at which Three Month Deposits are offered by it to prime banks in the London interbank market, as of approximately 11:00 a.m. London time on such Interest Determination Date, that is representative of single transactions at such time (the "Representative Amounts"). If at least two rate quotations are provided, LIBOR will be the arithmetic mean of the rate quotations obtained by the Calculation Agent.

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(2) In the event no Reported Rate appears on Telerate Page 3750 the Calculation Agent obtains fewer than two rate quotations, LIBOR will be the arithmetic mean of the rates quoted at approximately 11:00 a.m. New York City time on such Interest Determination Date by three major banks in New York City, selected by the Calculation Agent (after consultation with the Company), for Three Month Deposits in Representative Amounts to leading European banks, commencing on the second London Business Day immediately following such Interest Determination Date; provided, however, that if fewer than three banks selected by the Calculation Agent are quoting such rates, LIBOR for the applicable Interest Period will be the same as LIBOR in effect for the immediately preceding Interest Period.

"Interest Determination Date" for an Interest Period means the second London Business Day immediately preceding the first day of such Interest Period.

"Interest Period" means the period commencing on an Interest Payment Date (or commencing on the Original Issue Date, if no interest has been paid or duly made available for payment since that date) and ending on the day before the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

"LIBOR" for any Interest Determination Date will be the rate for deposits in U.S. dollars having a maturity of three months for a period commencing on the second London Business Day immediately following the Interest Determination Date ("Three Month Deposits"), as such rate appears on Telerate Page 3750 or a successor reporter of such rates selected by the Calculation Agent and acceptable to the Company, at approximately 11:00 a.m. London time on the Interest Determination Date (the "Reported Rate"); provided, however, that in certain circumstances described above, LIBOR will be determined in an alternative manner.

"London Business Day" means a day on which dealings in deposits in U.S. dollars are transacted, or with respect to any future date, are expected to be transacted, in the London interbank market.

"Telerate Page 3750" means the display designated as Page 3750 on Bridge Telerate, Inc., or any successor service, for the purpose of displaying London interbank rates of major banks for U.S. dollar deposits.

Upon request, the Calculation Agent will provide the current Interest Rate and, if determined, the Interest Rate which will become effective for the next Interest Period.

All percentages resulting from any calculation of the Interest Rate will be rounded, if necessary, to the nearest one-hundred thousandth of a percentage point, with five one-millionths of a percentage point rounded upwards, and all dollar amounts used in or resulting from such calculation will be rounded to the nearest cent (with one-half cent being rounded upwards).

Interest payments for this Note shall be computed for each Interest Period on the basis of a year consisting of 360 days and paid for the actual number of days for which interest is payable in that Interest Period. If any Interest Payment Date falls on a day that is not a Business Day, the Interest Payment Date will be the next succeeding Business Day. If the Maturity Date of this Note falls on a day that is not a Business Day, the payment of principal and interest will be made

A-4

on the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after the Maturity Date. This Note shall not be redeemable prior to the Maturity Date.

The Company, at its option, and subject to the terms and conditions provided in the Indenture, will be discharged from any and all obligations in respect of the Notes (except for certain obligations including obligations to register the transfer or exchange of Notes, replace stolen, lost or mutilated Notes, maintain paying agencies and hold monies for payment in trust, all as set forth in the Indenture) if the Company deposits with the Trustee money, U.S. Government Obligations which through the payment of interest thereon and principal thereof in accordance with their terms will provide money, or a combination of money and U.S. Government Obligations, in any event in an amount sufficient, without reinvestment, to pay all the principal of and any premium and interest on the Notes on the dates such payments are due in accordance with the terms of the Notes.

If an Event of Default shall occur and be continuing with respect to the Notes, the principal of and interest on the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modifications of the rights and obligations of the Company and the rights of the Noteholders under the Indenture at any time by the Company and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the outstanding Notes. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange therefor or in lieu thereof whether or not notation of such consent or waiver is made upon this Note.

As set forth in and subject to the provisions of the Indenture, no Holder of any notes issued under the Indenture will have any right to institute any proceeding with respect to the Indenture or for any remedy thereunder unless such Holder shall have previously given to the Trustee written notice of a continuing Event of Default with respect to such Notes, the Holders of a majority in aggregate principal amount of the outstanding Notes of all series under the Indenture in respect of which an Event of Default has occurred and is continuing, considered as one class, shall have made written request and offered reasonable indemnity to the Trustee to institute such proceeding as Trustee and the Trustee shall have failed to institute such proceeding within 60 days; PROVIDED, HOWEVER, that such limitations do not apply to a suit instituted by the Holder hereof for the enforcement of payment of the principal of and any premium or interest on this Note on or after the respective due dates expressed here.

No reference herein to the Indenture and to provisions of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, places and rates and the coin or currency prescribed in the Indenture.

As provided in the Indenture and subject to certain limitations therein set forth, this Note may be transferred only as permitted by the legend hereto and the provisions of the Indenture.

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The Indenture and the Notes shall be governed by, and construed in accordance with, the laws of the State of New York without regard to conflicts of law principles thereof.

Unless the certificate of authentication hereon has been executed by the Trustee, directly or through an Authenticating Agent by manual signature of an authorized officer, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

All terms used in this Note that are defined in the Indenture shall have the meanings assigned to them in the Indenture unless otherwise indicated herein.

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IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

AMEREN CORPORATION

By:

Title:

Attest:

Title:

TRUSTEE'S CERTIFICATE
OF AUTHENTICATION

Dated: December __, 2001

This Note is one of the Notes of the series herein designated, described or provided for in the within- mentioned Indenture.

THE BANK OF NEW YORK, AS TRUSTEE

By:________________________________
AUTHORIZED SIGNATORY

A-7

SCHEDULE I

[144A][REGULATION S] GLOBAL SECURITY

The initial principal amount of Notes evidenced by this Global Note is $150,000,000.

CHANGES TO PRINCIPAL AMOUNT OF NOTES EVIDENCED BY GLOBAL NOTE

------------------------------- ---------------------------- ---------------------------- ----------------------------
                                 Principal Amount of Notes
                                 by which this Global Note
                                    is to be Reduced or      Remaining Principal Amount
                                 Increased, and Reason for     of Notes Represented by
             Date                  Reduction or Increase          this Global Note             Notation Made by
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A-8

EXHIBIT A-1

CERTIFICATE OF TRANSFER

AMEREN CORPORATION

Floating Rate Notes due December 12, 2003

FOR VALUE RECEIVED, the undersigned sells, assigns and transfers unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

Name and address of assignee must be printed or typewritten. $

principal amount of beneficial interest in the referenced Security of the Company and does hereby irrevocably constitute and appoint

to transfer the said beneficial interest in such Security, with full power of substitution in the premises.

The undersigned certifies that said beneficial interest in said Security is being resold, pledged or otherwise transferred as follows:
(check one)

/ / to the Company;

/ / to a Person whom the undersigned reasonably believes is a qualified institutional buyer within the meaning of Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"), purchasing for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A;

/ / in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act;

/ / to an institution that is an "accredited investor" as defined in Rule
501(a)(1), (2), (3) or (7) under the Securities Act that is acquiring this Security for investment purposes and not for distribution (attach a copy of an Accredited Investor Certificate in the form annexed signed by an authorized officer of the transferee);

/ / as otherwise permitted by the non-registration legend appearing on this Security; or

/ / as otherwise agreed by the Company, confirmed in writing to the Trustee, as follows: [describe]

Dated:_________________             Signature:________________________

                                    NOTICE: The signature to this assignment
                                    must correspond with the name as written
                                    upon the face of the within instrument in
                                    every particular without alteration or
                                    enlargement, or any change whatever.

SIGNATURE GUARANTEE

Signatures must be guaranteed by an "eligible guarantor institution" meeting the requirement of the registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program ("STAMP") or such other "signature guarantee program" as may be determined by the registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.

A-1-1


[FORM OF INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATE]

[Transferor Name and Address]

Ladies and Gentlemen:

In connection with our proposed purchase of Floating Rate Notes due December 12, 2003 (the "Notes") issued by Ameren Corporation (the "Issuer"), we confirm that:

1. We have received a copy of the Offering Memorandum (the "Offering Memorandum") relating to the Notes and such other information as we deem necessary in order to make our investment decision. We acknowledge that we have read and agree to the matters stated under the caption NOTICE TO INVESTORS in such Offering Memorandum, and the restrictions on duplication or circulation of, or disclosure relating to, such Offering Memorandum.

2. We understand that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth in the Indenture relating to the Notes (the "Indenture") and that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth under NOTICE TO INVESTORS in the Offering Memorandum and the undersigned agrees to be bound by, and not to resell, pledge or otherwise transfer the Notes except in compliance with such restrictions and conditions and the Securities Act of 1933, as amended (the "Securities Act").

3. We understand that the offer and sale of the Notes have not been registered under the Securities Act, and that the Notes may not be offered or sold except as permitted in the following sentence. We agree, on our own behalf and on behalf of any accounts for which we are acting as hereinafter stated, that if we sell any Notes, we will do so only (A) to the Company, (B) so long as the Notes are eligible for resale pursuant to Rule 144A under the Securities Act ("Rule 144A"), to a person whom we reasonably believe is a "qualified institutional buyer" within the meaning of Rule 144A that purchases for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A, (C) to an institutional "accredited investor" (as defined below) that, prior to such transfer, furnishes to the Trustee (as defined in the Indenture) a signed letter containing certain representations and agreements relating to the restrictions on transfer of the Notes (substantially in the form of this letter), (D) in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act, (E) pursuant to the exemption from registration provided by Rule 144 under the Securities Act (if available), or (F) in accordance with another applicable exemption from the registration requirements of, or in a transaction not subject to, the Securities Act or pursuant to an effective registration statement under the Securities Act, and we further agree to provide to any person purchasing any of the Notes from us a notice advising such purchaser that resales of the Notes are restricted as stated herein.

A-1-2


4. We understand that, on any proposed resale of any Notes, we will be required to furnish to the Trustee and the Issuer such certification and other information as the Trustee and the Issuer may reasonably require to confirm that the proposed sale complies with the foregoing restrictions. We further understand that the Notes purchased by us will bear a legend to the foregoing effect.

5. We are an institutional "accredited investor" (as defined in Rule
501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act) and have such knowledge and experience in financial and business matters as to be capable of evaluating the merits and risks of our investment in the Notes, and we and any accounts for which we are acting are each able to bear the economic risk of our or its investment.

6. We are acquiring the Notes purchased by us for our own account or for one or more accounts (each of which is an institutional "accredited investor") as to each of which we exercise sole investment discretion.

You, the Issuer and the Trustee are entitled to rely upon this letter and are irrevocably authorized to produce this letter or a copy hereof to any interested party in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby.

Very truly yours,

By:___________________________ Name:


Title:

A-1-3


EXHIBIT B

FORM OF DEFINITIVE NOTE

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"). THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED PRIOR TO THE DATE WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUANCE DATE THEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE THEREOF WAS THE OWNER OF THIS SECURITY OR THE EXPIRATION OF SUCH SHORTER PERIOD AS MAY BE PRESCRIBED BY RULE 144(k), OR ANY SUCCESSOR PROVISION THEREOF, UNDER THE SECURITIES ACT (THE "RESALE RESTRICTION TERMINATION DATE") OTHER THAN (1) TO THE COMPANY, (2) IN A TRANSACTION ENTITLED TO AN EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT,
(3) SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE RESALE, PLEDGE OR OTHER TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ON THE REVERSE OF THIS SECURITY), (4) IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE SECURITIES ACT (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ON THE REVERSE OF THIS SECURITY), (5) TO AN INSTITUTION THAT IS AN "ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a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

B-1

AMEREN CORPORATION
FLOATING RATE NOTE DUE DECEMBER 12, 2003

CUSIP/ISIN: PRINCIPAL AMOUNT:

ORIGINAL ISSUE DATE: December 12, 2001 MATURITY DATE: December 12, 2003

INTEREST RATE: Floating, as set forth below NUMBER:

AMEREN CORPORATION, a corporation of the State of Missouri (the "COMPANY"), for value received hereby promises to pay to ____________ or registered assigns, the principal amount specified above on the Maturity Date set forth above, and to pay interest thereon from and including the Original Issue Date specified above or from and including the most recent date to which interest has been paid or duly provided for, semi-annually in arrears on March 12, June 12, September 12 and December 12 in each year, commencing March 12, 2002, and on the Maturity Date, at the per annum Interest Rate determined by the Calculation Agent on each Interest Determination Date, as such terms are defined herein, until the principal hereof is paid or made available for payment. No interest shall accrue on the Maturity Date, so long as the principal amount of this Note is paid in full on the Maturity Date. The interest so payable and punctually paid or duly provided for on any such Interest Payment Date will (except for interest payable on the Maturity Date or, if applicable, upon redemption or acceleration), as provided in the Indenture (as defined below), be paid to the Person in whose name this Note is registered at the close of business on the Regular Record Date for such interest, which shall be the fifteenth calendar day , as the case may be, next preceding such Interest Payment Date; provided that the first Interest Payment Date for any Note, the Original Issue Date of which is after a Regular Record Date but prior to the applicable Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date; and provided, that interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration, shall be payable to the Person to whom principal shall be payable. Except as otherwise provided in the Indenture (referred to on the reverse hereof), any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and shall be paid to the Person in whose name this Note is registered at the close of business on a Special Record Date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Noteholders not more than fifteen days nor fewer than ten days prior to such Special Record Date. Principal, applicable premium and interest due at the Maturity of this Note shall be payable in immediately available funds when due upon presentation and surrender of this Note at the corporate trust office of the Trustee or at the authorized office of any paying agent in the Borough of Manhattan, The City and State of New York or St. Louis, Missouri. Interest on this Note (other than interest payable at Maturity) shall be paid by check payable in clearinghouse funds to the Holder as its name appears on the register; provided, that if the Trustee receives a written request from any Holder of Notes, the aggregate principal amount of all of which having the same Interest Payment Date as this Note equals or exceeds $10,000,000, on or before the applicable Regular Record Date for such Interest Payment Date, interest on the Note shall be paid by wire transfer of immediately available funds to a bank within the continental United States (designated by such Holder in its request or by direct deposit into the account of such Holder designated by such Holder in its request if such account is maintained with the Trustee or any paying agent.

B-2

REFERENCE IS HEREBY MADE TO THE FURTHER PROVISIONS OF THIS NOTE SET FORTH IN FULL ON THE REVERSE HEREOF, WHICH FURTHER PROVISIONS SHALL FOR ALL PURPOSES HAVE THE SAME EFFECT AS IF SET FORTH IN FULL AT THIS PLACE.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, directly or through an Authenticating Agent by manual signature of an authorized officer, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

AMEREN CORPORATION

By:         _____________________________

Title:      _____________________________

Attest:     _____________________________

Title:      _____________________________

TRUSTEE'S CERTIFICATE
OF AUTHENTICATION

Dated: December __, 2001

This Note is one of the Notes of the series herein designated, described or provided for in the within-mentioned Indenture.

THE BANK OF NEW YORK, AS TRUSTEE

By:__________________________________
AUTHORIZED SIGNATORY

B-3

[FORM OF REVERSE OF NOTE]
AMEREN CORPORATION
FLOATING RATE NOTE DUE DECEMBER 12, 2003

This Note is one of a duly authorized issue of Floating Rate Notes due December 12, 2003 (the "NOTES OF THIS SERIES") of the Company issued and to be issued under an Indenture dated as of December 1, 2001, between the Company and The Bank of New York, as trustee (herein called the "TRUSTEE", which term includes any successor Trustee under the Indenture) and indentures supplemental thereto (collectively, the "INDENTURE"). Under the Indenture, one or more series of notes may be issued and, as used herein, the term "Notes" refers to the Notes of this Series. Reference is hereby made to the Indenture for a more complete statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Noteholders and of the terms upon which the Notes are and are to be authenticated and delivered. This Note is one of the series designated on the face hereof, issued in the aggregate principal amount of $150,000,000.

Each Note of this Series shall be dated and issued as of the date of its authentication by the Trustee and shall bear an Original Issue Date. Each Note of this Series issued upon transfer, exchange or substitution of such Note shall bear the Original Issue Date of such transferred, exchanged or substituted Note, as the case may be.

This Note will bear interest for each Interest Period at a per annum rate ("Interest Rate") determined by The Bank of New York, or its successor appointed by the Company acting as calculation agent (the "Calculation Agent"), subject to the maximum interest rate permitted by New York or other applicable state law, as such law may be modified by United States law of general application. The Interest Rate for each Interest Period will be equal to three month LIBOR on the Interest Determination Date for such Interest Period plus 0.95%. Promptly upon such determination, the Calculation Agent will notify the Trustee for the Notes, if the Trustee is not then serving as the Calculation Agent, of the Interest Rate for the new Interest Period. The Interest Rate determined by the Calculation Agent, absent willful default, bad faith or manifest error, shall be binding and conclusive upon the beneficial owners and holders of this Note, the Company and the Trustee.

Interest on this Note will accrue from and including the Original Issue Date specified above to, but excluding, March 12, 2002, and thereafter, from and including each Interest Payment Date to, but excluding, the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

If the following circumstances exist on any Interest Determination Date, the Calculation Agent shall determine LIBOR for the Notes as follows:

(1) In the event no Reported Rate appears on Telerate Page 3750 as of approximately 11:00 a.m. London time on an Interest Determination Date, the Calculation Agent shall request the principal London offices of each of four major banks in the London interbank market selected by the Calculation Agent (after consultation with the Company) to provide a quotation of the rate at which Three Month Deposits are offered by it to prime banks in the London interbank market, as of approximately 11:00 a.m. London time on such Interest Determination

B-4

Date, that is representative of single transactions at such time (the "Representative Amounts"). If at least two rate quotations are provided, LIBOR will be the arithmetic mean of the rate quotations obtained by the Calculation Agent.

(2) In the event no Reported Rate appears on Telerate Page 3750 the Calculation Agent obtains fewer than two rate quotations, LIBOR will be the arithmetic mean of the rates quoted at approximately 11:00 a.m. New York City time on such Interest Determination Date by three major banks in New York City, selected by the Calculation Agent (after consultation with the Company), for Three Month Deposits in Representative Amounts to leading European banks, commencing on the second London Business Day immediately following such Interest Determination Date; provided, however, that if fewer than three banks selected by the Calculation Agent are quoting such rates, LIBOR for the applicable Interest Period will be the same as LIBOR in effect for the immediately preceding Interest Period.

"Interest Determination Date" for an Interest Period means the second London Business Day immediately preceding the first day of such Interest Period.

"Interest Period" means the period commencing on an Interest Payment Date (or commencing on the Original Issue Date, if no interest has been paid or duly made available for payment since that date) and ending on the day before the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

"LIBOR" for any Interest Determination Date will be the rate for deposits in U.S. dollars having a maturity of three months for a period commencing on the second London Business Day immediately following the Interest Determination Date ("Three Month Deposits"), as such rate appears on Telerate Page 3750 or a successor reporter of such rates selected by the Calculation Agent and acceptable to the Company, at approximately 11:00 a.m. London time on the Interest Determination Date (the "Reported Rate"); provided, however, that in certain circumstances described above, LIBOR will be determined in an alternative manner.

"London Business Day" means a day on which dealings in deposits in U.S. dollars are transacted, or with respect to any future date, are expected to be transacted, in the London interbank market.

"Telerate Page 3750" means the display designated as Page 3750 on Bridge Telerate, Inc., or any successor service, for the purpose of displaying London interbank rates of major banks for U.S. dollar deposits.

Upon request, the Calculation Agent will provide the current Interest Rate and, if determined, the Interest Rate which will become effective for the next Interest Period.

All percentages resulting from any calculation of the Interest Rate will be rounded, if necessary, to the nearest one-hundred thousandth of a percentage point, with five one-millionths of a percentage point rounded upwards, and all dollar amounts used in or resulting from such calculation will be rounded to the nearest cent (with one-half cent being rounded upwards).

Interest payments for this Note shall be computed for each Interest Period on the basis of a year consisting of 360 days and paid for the actual number of days for which interest is payable

B-5

in that Interest Period. If any Interest Payment Date falls on a day that is not a Business Day, the Interest Payment Date will be the next succeeding Business Day. If the Maturity Date of this Note falls on a day that is not a Business Day, the payment of principal and interest will be made on the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after the Maturity Date. This Note shall not be redeemable prior to the Maturity Date.

The Company, at its option, and subject to the terms and conditions provided in the Indenture, will be discharged from any and all obligations in respect of the Notes (except for certain obligations including obligations to register the transfer or exchange of Notes, replace stolen, lost or mutilated Notes, maintain paying agencies and hold monies for payment in trust, all as set forth in the Indenture) if the Company deposits with the Trustee money, U.S. Government Obligations which through the payment of interest thereon and principal thereof in accordance with their terms will provide money, or a combination of money and U.S. Government Obligations, in any event in an amount sufficient, without reinvestment, to pay all the principal of and any premium and interest on the Notes on the dates such payments are due in accordance with the terms of the Notes.

If an Event of Default shall occur and be continuing with respect to the Notes, the principal of and interest on the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modifications of the rights and obligations of the Company and the rights of the Noteholders under the Indenture at any time by the Company and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the outstanding Notes. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange therefor in lieu thereof whether or not notation of such consent or waiver is made upon the Note.

As set forth in and subject to the provisions of the Indenture, no Holder of any notes issued under the Indenture will have any right to institute any proceeding with respect to the Indenture or for any remedy thereunder unless such Holder shall have previously given to the Trustee written notice of a continuing Event of Default with respect to such Notes, the Holders of a majority in aggregate principal amount of the outstanding Notes of all series under the Indenture in respect of which on Event of Default has occurred and is continuing, considered as one class, shall have made written request and offered reasonable indemnity to the Trustee to institute such proceeding as Trustee and the Trustee shall have failed to institute such proceeding within 60 days; provided, however, that such limitations do not apply to a suit instituted by the Holder hereof for the enforcement of payment of the principal of and any premium or interest on this Note on or after the respective due dates expressed here.

No reference herein to the Indenture and to provisions of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, places and rates and the coin or currency prescribed in the Indenture.

B-6

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the Note register. Upon surrender of this Note for registration or transfer at the corporate trust office of the Trustee or such other office or agency as may be designated by the Company in the Borough of Manhattan, the City and State of New York, or St. Louis, Missouri, endorsed by or accompanied by a written instrument of transfer in form satisfactory to the Company and the Note registrar, duly executed by the Holder hereof or the attorney in fact of such Holder duly authorized in writing, one or more new Notes of this Series of like tenor and of authorized denominations and for the same aggregate principal amount will be issued to the designated transferee or transferees.

The Notes of this Series are issuable only in registered form, without coupons, in denominations of $100,000 and integral multiples of $1,000 thereof. As provided in the Indenture and subject to certain limitations therein set forth, Notes of this Series are exchangeable for a like aggregate principal amount of Notes of this Series of like tenor and of a different authorized denomination, as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Note for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Note is registered as the owner thereof for all purposes, whether or not this Note is overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

The Indenture and the Notes shall be governed by, and construed in accordance with, the laws of the State of New York without regard to conflicts of law principles thereof.

All terms used in this Note that are defined in the Indenture shall have the meanings assigned to them in the Indenture.

B-7

ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this instrument, shall be construed as though they were written out in full according to applicable laws or regulations:

TEN COM -- as tenants in common           UNIF GIFT
                                          MIN ACT -   _____ Custodian ______
                                                      (Cust)          (Minor)
TEN ENT -- as tenants by the
entireties                                Under Uniform Gifts to Minors

JT TEN -- as joint tenants with right
of survivorship and not as tenants in
common                                    ______________________________
                                                       State

Additional abbreviations may also be used though not in the above list.


B-8

CERTIFICATE OF TRANSFER

AMEREN CORPORATION

Floating Rate Notes due December 12, 2003

FOR VALUE RECEIVED, the undersigned sells, assigns and transfers unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

Name and address of assignee must be printed or typewritten.

$

principal amount of beneficial interest in the referenced Security of the Company and does hereby irrevocably constitute and appoint

to transfer the said beneficial interest in such Security, with full power of substitution in the premises.

The undersigned certifies that said beneficial interest in said Security is being resold, pledged or otherwise transferred as follows:
(check one)

/ / to the Company;

/ / to a Person whom the undersigned reasonably believes is a qualified institutional buyer within the meaning of Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"), purchasing for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A;

/ / in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act;

/ / to an institution that is an "accredited investor" as defined in Rule
501(a)(1), (2), (3) or (7) under the Securities Act that is acquiring this Security for investment purposes and not for distribution (attach a copy of an Accredited Investor Certificate in the form annexed signed by an authorized officer of the transferee);

/ / as otherwise permitted by the non-registration legend appearing on this Security; or

/ / as otherwise agreed by the Company, confirmed in writing to the Trustee, as follows: [describe]

Dated:_________________             Signature:________________________

                                    NOTICE: The signature to this assignment
                                    must correspond with the name as written
                                    upon the face of the within instrument in
                                    every particular without alteration or
                                    enlargement, or any change whatever.

SIGNATURE GUARANTEE

Signatures must be guaranteed by an "eligible guarantor institution" meeting the requirement of the registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program ("STAMP") or such other "signature guarantee program" as may be determined by the registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.

B-9

[FORM OF INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATE]

[Transferor Name and Address]

Ladies and Gentlemen:

In connection with our proposed purchase of Floating Rate Notes due December 12, 2003 (the "Notes") issued by Ameren Corporation (the "Issuer"), we confirm that:

1. We have received a copy of the Offering Memorandum (the "Offering Memorandum") relating to the Notes and such other information as we deem necessary in order to make our investment decision. We acknowledge that we have read and agree to the matters stated under the caption NOTICE TO INVESTORS in such Offering Memorandum, and the restrictions on duplication or circulation of, or disclosure relating to, such Offering Memorandum.

2. We understand that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth in the Indenture relating to the Notes (the "Indenture") and that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth under NOTICE TO INVESTORS in the Offering Memorandum and the undersigned agrees to be bound by, and not to resell, pledge or otherwise transfer the Notes except in compliance with such restrictions and conditions and the Securities Act of 1933, as amended (the "Securities Act").

3. We understand that the offer and sale of the Notes have not been registered under the Securities Act, and that the Notes may not be offered or sold except as permitted in the following sentence. We agree, on our own behalf and on behalf of any accounts for which we are acting as hereinafter stated, that if we sell any Notes, we will do so only (A) to the Company, (B) so long as the Notes are eligible for resale pursuant to Rule 144A under the Securities Act ("Rule 144A"), to a person whom we reasonably believe is a "qualified institutional buyer" within the meaning of Rule 144A that purchases for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A, (C) to an institutional "accredited investor" (as defined below) that, prior to such transfer, furnishes to the Trustee (as defined in the Indenture) a signed letter containing certain representations and agreements relating to the restrictions on transfer of the Notes (substantially in the form of this letter), (D) in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act, (E) pursuant to the exemption from registration provided by Rule 144 under the Securities Act (if available), or (F) in accordance with another applicable exemption from the registration requirements of, or in a transaction not subject to, the Securities Act or pursuant to an effective registration statement under the Securities Act, and we further agree to provide to any person purchasing any of the Notes from us a notice advising such purchaser that resales of the Notes are restricted as stated herein.

B-10

4. We understand that, on any proposed resale of any Notes, we will be required to furnish to the Trustee and the Issuer such certification and other information as the Trustee and the Issuer may reasonably require to confirm that the proposed sale complies with the foregoing restrictions. We further understand that the Notes purchased by us will bear a legend to the foregoing effect.

5. We are an institutional "accredited investor" (as defined in Rule
501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act) and have such knowledge and experience in financial and business matters as to be capable of evaluating the merits and risks of our investment in the Notes, and we and any accounts for which we are acting are each able to bear the economic risk of our or its investment.

6. We are acquiring the Notes purchased by us for our own account or for one or more accounts (each of which is an institutional "accredited investor") as to each of which we exercise sole investment discretion.

You, the Issuer and the Trustee are entitled to rely upon this letter and are irrevocably authorized to produce this letter or a copy hereof to any interested party in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby.

Very truly yours,

By:___________________________ Name:


Title:

B-11

EXHIBIT 4.7

COMPANY ORDER

January 24, 2002

The Bank of New York
c/o BNY Trust Company of Missouri
911 Washington Street
St. Louis, Missouri 63101

Ladies and Gentlemen:

Application is hereby made to The Bank of New York, a New York banking corporation, as trustee (the "Trustee"), under the Indenture dated as of December 1, 2001 (the "Indenture"), between Ameren Corporation, a Missouri corporation (the "Company"), and the Trustee for the authentication and delivery of $100,000,000 aggregate principal amount of the Company's 5.70% Notes due February 1, 2007 (the "Notes"), pursuant to the provisions of Article II of the Indenture. Additional Notes without limitation as to amount, and without the consent of the holders of the then Outstanding Notes, may also be authenticated and delivered in the manner provided in Section 2.05 of the Indenture. All capitalized terms not defined herein that are defined in the Indenture shall have the same meaning as used in the Indenture.

The Notes will be initially issued pursuant to Section 4(2) of the Securities Act of 1933, as amended (the "Securities Act"), in the form of Global Notes registered in the name of Cede & Co. (as nominee for The Depository Trust Company ("DTC"), New York, New York, which will act as the Depositary for the Global Notes). Pursuant to Section 2.05(c) of the Indenture, the Notes will have the terms set forth in the form of Global Note attached hereto as Exhibit A and in the form of definitive Note attached hereto as Exhibit B (which terms are incorporated by reference in this Company Order). The Global Notes shall bear the depository legend in substantially the form set forth in Exhibit A attached hereto. The Notes shall be subject to restrictions on transfer, and each Note, whether in global form or in definitive form, shall bear the non-registration legend set forth in substantially the form in the applicable form of Note, unless otherwise agreed by the Company, such agreement to be confirmed in writing to the Trustee. Nothing in the Indenture or the Notes shall be construed to require the Company to register any of the Notes under the Securities Act, unless otherwise expressly agreed by the Company, confirmed in writing to the Trustee, or to make any transfer of the Notes or the beneficial interests therein in violation of applicable law. The Notes will be issued only in denominations of $100,000 and in integral multiples of $1,000 in excess thereof.

It is contemplated that beneficial interests in the Notes owned by qualified institutional buyers (as defined in Rule 144A under the Securities Act) ("QIBs") or sold to QIBs in reliance upon Rule 144A under the Securities Act will be represented by one or more separate Global Notes (each, a "Rule 144A Global Certificate") registered in the name of Cede & Co., as registered owner and as nominee for DTC; beneficial interests in the Notes sold to purchasers pursuant to Regulation S under the Securities Act will be evidenced by one or more separate Global Notes (each, a "Regulation S Global Certificate") and will be registered in the name of


Cede & Co., as registered owner and as nominee for DTC for the accounts of The Euroclear System or Clearstream Banking, Luxembourg, societe anonyme; prior to the 40th day after the date of initial issuance of the Notes, beneficial interests in a Regulation S Global Certificate may be held only through The Euroclear System or Clearstream Banking, Luxembourg, societe anonyme (unless a resale or transfer is effected pursuant to Rule 144A under the Securities Act); Notes acquired by Institutional Accredited Investors (as defined in Rule
501(a)(1), (2), (3) or (7) under the Securities Act) ("IAIs"), who are not QIBs and who are not purchasers pursuant to Regulation S under the Securities Act, will be in definitive form. The Trustee and the Company will have no responsibility or liability for any aspect of transfers of beneficial interests in the Notes (which transfers will be conducted pursuant to the customary procedures of DTC), any records of DTC of beneficial interests or any transactions between DTC and its participants or between any such participants and any other beneficial owners or for monitoring, supervising or reviewing of any thereof.

In connection with any transfer of Notes, the Trustee and the Company shall be under no duty to inquire into, may conclusively presume the correctness of, and shall be fully protected in relying upon the certificates and other information (set forth in the form of definitive Note attached hereto as Exhibit B, for use in connection with the transfer of the Notes in definitive form, or set forth in Exhibit A-1 attached hereto, for use in connection with the transfer of beneficial interests between a Rule 144A Global Certificate and a Regulation S Global Certificate or to a Note in definitive form, or otherwise) received from the Holders and any transferees of any Notes regarding the validity, legality and due authorization of any such transfer, the eligibility of the transferee to receive such Note and any other facts and circumstances related to such transfer. Transfers of beneficial interests between a Rule 144A Global Certificate and a Regulation S Global Certificate, and other transfers relating to beneficial interests in the Notes in global form, shall be reflected by endorsements of the Trustee, as custodian for DTC, on the schedule attached to such certificate.

In connection with this Company Order, there are delivered to you herewith the following:

1. Certified copies of the resolutions adopted by the Board of Directors of the Company and by the Executive Committee of the Board of Directors of the Company authorizing this Company Order and the issuance and sale of the Notes by the Company pursuant to Section 2.05(c)(1) of the Indenture;

2. Opinions of Counsel addressed to you or in which it is stated that you may rely pursuant to Section 2.05(c)(2) of the Indenture;

3. Officers' Certificate pursuant to Section 2.05(c)(3) of the Indenture; and

4. Two Global Notes representing the Notes executed on behalf of the Company in accordance with the terms of Section 2.05(a) of the Indenture.

You are hereby instructed to authenticate the Global Notes representing the Notes and hold them as DTC's custodian. The Global Notes representing the Notes are to be held for delivery through the facilities of DTC to the initial purchasers thereof against payment therefor at

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the closing in respect of the sale thereof, such closing to be held at 10:00
a.m., New York time, January 24, 2002, at the offices of Pillsbury Winthrop LLP, One Battery Park Plaza, New York, NY 10004.

Please acknowledge receipt of the Global Notes representing the Notes, the instructions referred to above and the supporting documentation pursuant to the Indenture referred to above.

Very truly yours,

Ameren Corporation

By:  /s/ Jerre E. Birdsong
   ---------------------------
   Name:  Jerre E. Birdsong
   Title: Vice President and
          Treasurer

Receipt from the Company of the Global Notes representing the Notes, certain instructions related thereto and the supporting documentation pursuant to the Indenture in connection with the authentication and delivery of the Notes is hereby acknowledged.

The Bank of New York, as Trustee

By:  /s/ Albert Lundy
   ---------------------------
   Name:  Albert Lundy
   Title: As Agent for

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EXHIBIT A
FORM OF GLOBAL NOTE

THIS NOTE IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY (REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY AS PROVIDED IN THE INDENTURE REFERRED TO BELOW, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY. UNLESS THIS NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK), TO THE TRUSTEE FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS MADE TO CEDE & CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"). THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED PRIOR TO THE DATE WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUANCE DATE THEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE THEREOF WAS THE OWNER OF THIS SECURITY OR THE EXPIRATION OF SUCH SHORTER PERIOD AS MAY BE PRESCRIBED BY RULE 144(k), OR ANY SUCCESSOR PROVISION THEREOF, UNDER THE SECURITIES ACT (THE "RESALE RESTRICTION TERMINATION DATE") OTHER THAN (1) TO THE COMPANY, (2) IN A TRANSACTION ENTITLED TO AN EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT,
(3) SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE RESALE, PLEDGE OR OTHER TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (4) IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE SECURITIES ACT, (5) TO AN INSTITUTION THAT IS AN "ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS ACQUIRING THIS SECURITY FOR INVESTMENT PURPOSES AND NOT FOR DISTRIBUTION, AND A CERTIFICATE IN THE FORM ATTACHED TO THIS SECURITY IS DELIVERED BY THE TRANSFEREE TO

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THE COMPANY AND THE TRUSTEE OR (6) IN ACCORDANCE WITH ANOTHER APPLICABLE
EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT OR PURSUANT TO AN EFFECTIVE REGISTRATION
STATEMENT UNDER THE SECURITIES ACT, IN EACH CASE IN ACCORDANCE WITH ANY
APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES. THE FOREGOING
RESTRICTIONS ON RESALE WILL NOT APPLY SUBSEQUENT TO THE RESALE RESTRICTION
TERMINATION DATE.

                               AMEREN CORPORATION
                         5.70% NOTE DUE FEBRUARY 1, 2007

CUSIP/ISIN:                               NUMBER:

ORIGINAL ISSUE DATE: January 24, 2002     PRINCIPAL AMOUNT: Listed on Schedule
                                                            I hereto

INTEREST RATE: 5.70%                      MATURITY DATE: February 1, 2007

AMEREN CORPORATION, a corporation of the State of Missouri (the "COMPANY"), for value received hereby promises to pay to CEDE & CO. or registered assigns, the principal amount specified above on the Maturity Date set forth above, and to pay interest thereon from and including the Original Issue Date specified above or from and including the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually in arrears on the February 1 and August 1 in each year, commencing August 1, 2002, and on the Maturity Date, at the per annum interest rate set forth above until the principal hereof is paid or made available for payment. No interest shall accrue on the Maturity Date, so long as the principal amount of this Note is paid on the Maturity Date. The interest so payable and punctually paid or duly provided for on any such Interest Payment Date (except for interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration) will, as provided in the Indenture (as defined below), be paid to the Person in whose name this Note is registered at the close of business on the Regular Record Date for such interest, which shall be the fifteenth calendar day next preceding such Interest Payment Date; provided, that the first Interest Payment Date for any part of this Note, the Original Issue Date of which is after a Regular Record Date but prior to the applicable Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date; and provided, that interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration, shall be payable to the Person to whom principal shall be payable. Except as otherwise provided in the Indenture, any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and shall be paid to the Person in whose name this Note is registered at the close of business on a Special Record Date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Noteholders not more than fifteen days or fewer than ten days prior to such Special Record Date. Payment of the principal of and interest and premium on this shall be payable pursuant to Section 2.12(a) of the Indenture.

This Note is a Global Note in respect of a duly authorized issue of 5.70% Notes due February 1, 2007 (the "NOTES OF THIS SERIES", which term includes any Global Notes

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representing such Notes) of the Company issued and to be issued under an Indenture dated as of December 1, 2001 between the Company and The Bank of New York, as trustee (herein called the "TRUSTEE", which term includes any successor Trustee under the Indenture) and indentures supplemental thereto (collectively, the "INDENTURE"). Under the Indenture, one or more series of notes may be issued and, as used herein, the term "Notes" refers to the Notes of this Series. Reference is hereby made to the Indenture for a more complete statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Noteholders and of the terms upon which the Notes are and are to be authenticated and delivered. This Note has been issued in respect of the series designated on the first page hereof, issued in the initial aggregate principal amount of $100,000,000.

Each Note of this Series shall be dated and issued as of the date of its authentication by the Trustee and shall bear an Original Issue Date. Each Note of this Series issued upon transfer, exchange or substitution of such Note shall bear the Original Issue Date of such transferred, exchanged or substituted Note, as the case may be.

Interest on this Note will accrue from and including the Original Issue Date specified above to, but excluding, August 1, 2002, and thereafter, from and including each Interest Payment Date to, but excluding, the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

Interest payments for this Note shall be computed on the basis of a 360-day year consisting of twelve 30-day months. If any Interest Payment Date falls on a day that is not a Business Day, the Interest Payment Date will be the next succeeding Business Day (and without any interest or other payment in respect of any such delay). If the Maturity Date of this Note or any redemption date falls on a day that is not a Business Day, the payment of principal and interest will be made on the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after the Maturity Date or such redemption date.

The Company has the option to redeem all or any part of this Note at any time prior to its Maturity Date. The Company will give notice of any redemption at least 30 days, but not more than 60 days, before a redemption date. The Company will pay a redemption price equal to the sum of (i) 100% of the principal amount of this Note being redeemed, plus (ii) all accrued and unpaid interest on the principal amount of this Note being redeemed, plus (iii) any Make-Whole Premium.

The Company will appoint an independent investment banking institution of national standing to calculate the Make-Whole Premium. Lehman Brothers Inc. will make that calculation if (i) the Company does not appoint someone else at least 30 days before the redemption date or (ii) the institution the Company appoints is unwilling or unable to make the calculation. If Lehman Brothers Inc. is unwilling or unable to make the calculation, then the Trustee will appoint an independent investment banking institution of national standing to make the calculation.

The amount of the Make-Whole Premium, if any, will be equal to the excess of (i) the sum of the present values, calculated as of the redemption date, of
(a) each interest payment on

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each interest payment date after the redemption date that would have been paid on this Note (excluding any accrued interest paid at the redemption date) and
(b) the principal amount that would have been payable at the Maturity Date with respect to the principal amount of this Note being redeemed over (ii) the principal amount of this Note being redeemed.

An independent investment banker will calculate the present values of interest and principal payments in accordance with generally accepted principles of financial analysis. The present values will be calculated by discounting the amount of each payment of interest or principal from the date that each payment would have been paid to the redemption date on a semi-annual basis assuming a 360-day year consisting of twelve 30-day months at a discount rate that is equal to the Treasury Yield plus 25 basis points.

The "Treasury Yield" will be an annual interest rate that is equal to the weekly average yield to maturity of United States Treasury Notes having a constant maturity corresponding to the remaining term to maturity of this Note that will be redeemed. This interest rate will be calculated to the nearest 1/12th of a year. The independent investment banker will determine the Treasury Yield on the third Business Day before the redemption date.

The independent investment banker will determine the weekly average yields of United States Treasury Notes from the most recent statistical release published by the Federal Reserve Bank of New York entitled "H.15(519) Selected Interest Rates" ("H.15 Statistical Release") or any successor publication. If the H.15 Statistical Release gives a weekly average yield for United States Treasury Notes having a constant maturity that is the same as the remaining term of the Notes, then the Treasury Yield will equal that weekly average yield. In all other cases, the independent investment banker will calculate the Treasury Yield by interpolating, on a straight-line basis, the weekly average yields from the H.15 Statistical Release on the United States Treasury Notes having a constant maturity closest to but greater than the remaining term of the Notes and the United States Treasury Notes having a constant maturity closest to and less than the remaining term. The independent investment banker will round any weekly average yields calculated by interpolation to the nearest 1/100th of 1%, and will round the percentage up for any figure of 1/200th of 1% or above.

If weekly average yields for United States Treasury Notes are not available in the H.15 Statistical Release, or anywhere else, the independent investment banker will select comparable rates and calculate the Treasury Yield using these rates.

The Company, at its option, and subject to the terms and conditions provided in the Indenture, will be discharged from any and all obligations in respect of the Notes (except for certain obligations including obligations to register the transfer or exchange of Notes, replace stolen, lost or mutilated Notes, maintain paying agencies and hold monies for payment in trust, all as set forth in the Indenture) if the Company deposits with the Trustee money, U.S. Government Obligations which through the payment of interest thereon and principal thereof in accordance with their terms will provide money, or a combination of money and U.S. Government Obligations, in any event in an amount sufficient, without reinvestment, to pay all the principal of and any premium and interest on the Notes on the dates such payments are due in accordance with the terms of the Notes.

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If an Event of Default shall occur and be continuing with respect to the Notes, the principal of and interest on the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modifications of the rights and obligations of the Company and the rights of the Noteholders under the Indenture at any time by the Company and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the outstanding Notes. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange therefor or in lieu thereof whether or not notation of such consent or waiver is made upon this Note.

As set forth in and subject to the provisions of the Indenture, no Holder of any notes issued under the Indenture will have any right to institute any proceeding with respect to the Indenture or for any remedy thereunder unless such Holder shall have previously given to the Trustee written notice of a continuing Event of Default with respect to such Notes, the Holders of a majority in aggregate principal amount of the outstanding Notes of all series under the Indenture in respect of which an Event of Default has occurred and is continuing, considered as one class, shall have made written request and offered reasonable indemnity to the Trustee to institute such proceeding as Trustee and the Trustee shall have failed to institute such proceeding within 60 days; PROVIDED, HOWEVER, that such limitations do not apply to a suit instituted by the Holder hereof for the enforcement of payment of the principal of and any premium or interest on this Note on or after the respective due dates expressed here.

No reference herein to the Indenture and to provisions of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, places and rates and the coin or currency prescribed in the Indenture.

As provided in the Indenture and subject to certain limitations therein set forth, this Note may be transferred only as permitted by the legend hereto and the provisions of the Indenture.

The Indenture and the Notes shall be governed by, and construed in accordance with, the laws of the State of New York without regard to conflicts of law principles thereof.

Unless the certificate of authentication hereon has been executed by the Trustee, directly or through an Authenticating Agent by manual signature of an authorized officer, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

All terms used in this Note that are defined in the Indenture shall have the meanings assigned to them in the Indenture unless otherwise indicated herein.

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IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

AMEREN CORPORATION

By:

Title:

Attest:

Title:

TRUSTEE'S CERTIFICATE
OF AUTHENTICATION

Dated: January __, 2002

This Note is one of the Notes of the series herein designated, described or provided for in the within-mentioned Indenture.

THE BANK OF NEW YORK, AS TRUSTEE

By:________________________________
AUTHORIZED SIGNATORY

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SCHEDULE I

[144A][REGULATION S] GLOBAL SECURITY

The initial principal amount of Notes evidenced by this Global Note is $100,000,000.

CHANGES TO PRINCIPAL AMOUNT OF NOTES EVIDENCED BY GLOBAL NOTE

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                                 Principal Amount of Notes
                                 by which this Global Note
                                    is to be Reduced or      Remaining Principal Amount
                                 Increased, and Reason for     of Notes Represented by
             Date                  Reduction or Increase          this Global Note             Notation Made by
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EXHIBIT A-1

CERTIFICATE OF TRANSFER

AMEREN CORPORATION

5.70% Notes due February 1, 2007

FOR VALUE RECEIVED, the undersigned sells, assigns and transfers unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

Name and address of assignee must be printed or typewritten.

$

principal amount of beneficial interest in the referenced Security of the Company and does hereby irrevocably constitute and appoint

to transfer the said beneficial interest in such Security, with full power of substitution in the premises.

The undersigned certifies that said beneficial interest in said Security is being resold, pledged or otherwise transferred as follows:
(check one)

/ / to the Company;

/ / to a Person whom the undersigned reasonably believes is a qualified institutional buyer within the meaning of Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"), purchasing for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A;

/ / in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act;

/ / to an institution that is an "accredited investor" as defined in Rule
501(a)(1), (2), (3) or (7) under the Securities Act that is acquiring this Security for investment purposes and not for distribution (attach a copy of an Accredited Investor Certificate in the form annexed signed by an authorized officer of the transferee);

/ / as otherwise permitted by the non-registration legend appearing on this Security; or

/ / as otherwise agreed by the Company, confirmed in writing to the Trustee, as follows: [describe]

Dated:_________________             Signature:________________________

                                    NOTICE: The signature to this assignment
                                    must correspond with the name as written
                                    upon the face of the within instrument in
                                    every particular without alteration or
                                    enlargement, or any change whatever.

SIGNATURE GUARANTEE

Signatures must be guaranteed by an "eligible guarantor institution" meeting the requirement of the registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program ("STAMP") or such other "signature guarantee program" as may be determined by the registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.

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[FORM OF INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATE]

[Transferor Name and Address]

Ladies and Gentlemen:

In connection with our proposed purchase of 5.70% Notes due February 1, 2007 (the "Notes") issued by Ameren Corporation (the "Issuer"), we confirm that:

1. We have received a copy of the Offering Memorandum (the "Offering Memorandum") relating to the Notes and such other information as we deem necessary in order to make our investment decision. We acknowledge that we have read and agree to the matters stated under the caption NOTICE TO INVESTORS in such Offering Memorandum, and the restrictions on duplication or circulation of, or disclosure relating to, such Offering Memorandum.

2. We understand that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth in the Indenture relating to the Notes (the "Indenture") and that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth under NOTICE TO INVESTORS in the Offering Memorandum and the undersigned agrees to be bound by, and not to resell, pledge or otherwise transfer the Notes except in compliance with such restrictions and conditions and the Securities Act of 1933, as amended (the "Securities Act").

3. We understand that the offer and sale of the Notes have not been registered under the Securities Act, and that the Notes may not be offered or sold except as permitted in the following sentence. We agree, on our own behalf and on behalf of any accounts for which we are acting as hereinafter stated, that if we sell any Notes, we will do so only (A) to the Company, (B) so long as the Notes are eligible for resale pursuant to Rule 144A under the Securities Act ("Rule 144A"), to a person whom we reasonably believe is a "qualified institutional buyer" within the meaning of Rule 144A that purchases for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A, (C) to an institutional "accredited investor" (as defined below) that, prior to such transfer, furnishes to the Trustee (as defined in the Indenture) a signed letter containing certain representations and agreements relating to the restrictions on transfer of the Notes (substantially in the form of this letter), (D) in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act, (E) pursuant to the exemption from registration provided by Rule 144 under the Securities Act (if available), or (F) in accordance with another applicable exemption from the registration requirements of, or in a transaction not subject to, the Securities Act or pursuant to an effective registration statement under the Securities Act, and we further agree to provide to any person purchasing any of the Notes from us a notice advising such purchaser that resales of the Notes are restricted as stated herein.

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4. We understand that, on any proposed resale of any Notes, we will be required to furnish to the Trustee and the Issuer such certification and other information as the Trustee and the Issuer may reasonably require to confirm that the proposed sale complies with the foregoing restrictions. We further understand that the Notes purchased by us will bear a legend to the foregoing effect.

5. We are an institutional "accredited investor" (as defined in Rule
501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act) and have such knowledge and experience in financial and business matters as to be capable of evaluating the merits and risks of our investment in the Notes, and we and any accounts for which we are acting are each able to bear the economic risk of our or its investment.

6. We are acquiring the Notes purchased by us for our own account or for one or more accounts (each of which is an institutional "accredited investor") as to each of which we exercise sole investment discretion.

You, the Issuer and the Trustee are entitled to rely upon this letter and are irrevocably authorized to produce this letter or a copy hereof to any interested party in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby.

Very truly yours,

By:___________________________ Name:


Title:

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EXHIBIT B
FORM OF DEFINITIVE NOTE

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"). THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED PRIOR TO THE DATE WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUANCE DATE THEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE THEREOF WAS THE OWNER OF THIS SECURITY OR THE EXPIRATION OF SUCH SHORTER PERIOD AS MAY BE PRESCRIBED BY RULE 144(k), OR ANY SUCCESSOR PROVISION THEREOF, UNDER THE SECURITIES ACT (THE "RESALE RESTRICTION TERMINATION DATE") OTHER THAN (1) TO THE COMPANY, (2) IN A TRANSACTION ENTITLED TO AN EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT,
(3) SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE RESALE, PLEDGE OR OTHER TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ON THE REVERSE OF THIS SECURITY), (4) IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE SECURITIES ACT (AS INDICATED BY THE BOX CHECKED BY THE TRANSFEROR ON THE CERTIFICATE OF TRANSFER ON THE REVERSE OF THIS SECURITY), (5) TO AN INSTITUTION THAT IS AN "ACCREDITED INVESTOR" AS DEFINED IN RULE 501(a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AMEREN CORPORATION
5.70% NOTE DUE FEBRUARY 1, 2007

CUSIP/ISIN: PRINCIPAL AMOUNT:

ORIGINAL ISSUE DATE: January 24, 2002 MATURITY DATE: February 1, 2007

INTEREST RATE: 5.70% NUMBER:

AMEREN CORPORATION, a corporation of the State of Missouri (the "COMPANY"), for value received hereby promises to pay to ____________ or registered assigns, the principal amount specified above on the Maturity Date set forth above, and to pay interest thereon from and including the Original Issue Date specified above or from and including the most recent date to which interest has been paid or duly provided for, semi-annually in arrears on February 1 and August 1 in each year, commencing August 1, 2002, and on the Maturity Date, at the per annum interest rate set forth above until the principal hereof is paid or made available for payment. No interest shall accrue on the Maturity Date, so long as the principal amount of this Note is paid in full on the Maturity Date. The interest so payable and punctually paid or duly provided for on any such Interest Payment Date will (except for interest payable on the Maturity Date or, if applicable, upon redemption or acceleration), as provided in the Indenture (as defined below), be paid to the Person in whose name this Note is registered at the close of business on the Regular Record Date for such interest, which shall be the fifteenth calendar day, as the case may be, next preceding such Interest Payment Date; provided that the first Interest Payment Date for any Note, the Original Issue Date of which is after a Regular Record Date but prior to the applicable Interest Payment Date, shall be the Interest Payment Date following the next succeeding Regular Record Date; and provided, that interest payable on the Maturity Date set forth above or, if applicable, upon redemption or acceleration, shall be payable to the Person to whom principal shall be payable. Except as otherwise provided in the Indenture (referred to on the reverse hereof), any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and shall be paid to the Person in whose name this Note is registered at the close of business on a Special Record Date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Noteholders not more than fifteen days nor fewer than ten days prior to such Special Record Date. Principal, applicable premium and interest due at the Maturity of this Note shall be payable in immediately available funds when due upon presentation and surrender of this Note at the corporate trust office of the Trustee or at the authorized office of any paying agent in the Borough of Manhattan, The City and State of New York or St. Louis, Missouri. Interest on this Note (other than interest payable at Maturity) shall be paid by check payable in clearinghouse funds to the Holder as its name appears on the register; provided, that if the Trustee receives a written request from any Holder of Notes, the aggregate principal amount of all of which having the same Interest Payment Date as this Note equals or exceeds $10,000,000, on or before the applicable Regular Record Date for such Interest Payment Date, interest on the Note shall be paid by wire transfer of immediately available funds to a bank within the continental United States (designated by such Holder in its request or by direct deposit into the account of such Holder designated by such Holder in its request if such account is maintained with the Trustee or any paying agent).

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REFERENCE IS HEREBY MADE TO THE FURTHER PROVISIONS OF THIS NOTE SET FORTH IN FULL ON THE REVERSE HEREOF, WHICH FURTHER PROVISIONS SHALL FOR ALL PURPOSES HAVE THE SAME EFFECT AS IF SET FORTH IN FULL AT THIS PLACE.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, directly or through an Authenticating Agent by manual signature of an authorized officer, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

AMEREN CORPORATION

By:         _____________________________

Title:      _____________________________

Attest:     _____________________________

Title:      _____________________________

TRUSTEE'S CERTIFICATE
OF AUTHENTICATION

Dated: January __, 2002

This Note is one of the Notes of the series herein designated, described or provided for in the within- mentioned Indenture.

THE BANK OF NEW YORK, AS TRUSTEE

By:__________________________________
AUTHORIZED SIGNATORY

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[FORM OF REVERSE OF NOTE]
AMEREN CORPORATION
5.70% NOTE DUE FEBRUARY 1, 2007

This Note is one of a duly authorized issue of 5.70% Notes due February 1, 2007 (the "NOTES OF THIS SERIES") of the Company issued and to be issued under an Indenture dated as of December 1, 2001, between the Company and The Bank of New York, as trustee (herein called the "TRUSTEE", which term includes any successor Trustee under the Indenture) and indentures supplemental thereto (collectively, the "INDENTURE"). Under the Indenture, one or more series of notes may be issued and, as used herein, the term "Notes" refers to the Notes of this Series. Reference is hereby made to the Indenture for a more complete statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Noteholders and of the terms upon which the Notes are and are to be authenticated and delivered. This Note is one of the series designated on the face hereof, issued in the aggregate principal amount of $100,000,000.

Each Note of this Series shall be dated and issued as of the date of its authentication by the Trustee and shall bear an Original Issue Date. Each Note of this Series issued upon transfer, exchange or substitution of such Note shall bear the Original Issue Date of such transferred, exchanged or substituted Note, as the case may be.

Interest on this Note will accrue from and including the Original Issue Date specified above to, but excluding, August 1, 2002, and thereafter, from and including each Interest Payment Date to, but excluding, the next succeeding Interest Payment Date or the Maturity Date, as the case may be.

Interest payments for this Note shall be computed on the basis of a 360-day year consisting of twelve 30-day months. If any Interest Payment Date falls on a day that is not a Business Day, the Interest Payment Date will be the next succeeding Business Day (and without any interest or other payment in respect of any such delay). If the Maturity Date of this Note or any redemption date falls on a day that is not a Business Day, the payment of principal and interest will be made on the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after the Maturity Date or such redemption date.

The Company has the option to redeem all or any part of this Note at any time prior to its Maturity Date. The Company will give notice of any redemption at least 30 days, but not more than 60 days, before a redemption date. The Company will pay a redemption price equal to the sum of (i) 100% of the principal amount of this Note being redeemed, plus (ii) all accrued and unpaid interest on the principal amount of this Note being redeemed, plus (iii) any Make-Whole Premium.

The Company will appoint an independent investment banking institution of national standing to calculate the Make-Whole Premium. Lehman Brothers Inc. will make that calculation if (i) the Company does not appoint someone else at least 30 days before the redemption date or (ii) the institution the Company appoints is unwilling or unable to make the calculation. If Lehman Brothers Inc. is unwilling or unable to make the calculation, then the

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Trustee will appoint an independent investment banking institution of national standing to make the calculation.

The amount of the Make-Whole Premium, if any, will be equal to the excess of (i) the sum of the present values, calculated as of the redemption date, of
(a) each interest payment on each interest payment date after the redemption date that would have been paid on this Note (excluding any accrued interest paid at the redemption date) and (b) the principal amount that would have been payable at the Maturity Date with respect to the principal amount of this Note being redeemed over (ii) the principal amount of this Note being redeemed.

An independent investment banker will calculate the present values of interest and principal payments in accordance with generally accepted principles of financial analysis. The present values will be calculated by discounting the amount of each payment of interest or principal from the date that each payment would have been paid to the redemption date on a semi-annual basis assuming a 360-day year consisting of twelve 30-day months at a discount rate that is equal to the Treasury Yield plus 25 basis points.

The "Treasury Yield" will be an annual interest rate that is equal to the weekly average yield to maturity of United States Treasury Notes having a constant maturity corresponding to the remaining term to maturity of this Note that will be redeemed. This interest rate will be calculated to the nearest 1/12th of a year. The independent investment banker will determine the Treasury Yield on the third Business Day before the redemption date.

The independent investment banker will determine the weekly average yields of United States Treasury Notes from the most recent statistical release published by the Federal Reserve Bank of New York entitled "H.15(519) Selected Interest Rates" ("H.15 Statistical Release") or any successor publication. If the H.15 Statistical Release gives a weekly average yield for United States Treasury Notes having a constant maturity that is the same as the remaining term of the Notes, then the Treasury Yield will equal that weekly average yield. In all other cases, the independent investment banker will calculate the Treasury Yield by interpolating, on a straight-line basis, the weekly average yields from the H.15 Statistical Release on the United States Treasury Notes having a constant maturity closest to but greater than the remaining term of the Notes and the United States Treasury Notes having a constant maturity closest to and less than the remaining term. The independent investment banker will round any weekly average yields calculated by interpolation to the nearest 1/100th of 1%, and will round the percentage up for any figure of 1/200th of 1% or above.

If weekly average yields for United States Treasury Notes are not available in the H.15 Statistical Release, or anywhere else, the independent investment banker will select comparable rates and calculate the Treasury Yield using these rates.

The Company, at its option, and subject to the terms and conditions provided in the Indenture, will be discharged from any and all obligations in respect of the Notes (except for certain obligations including obligations to register the transfer or exchange of Notes, replace stolen, lost or mutilated Notes, maintain paying agencies and hold monies for payment in trust, all as set forth in the Indenture) if the Company deposits with the Trustee money, U.S. Government Obligations which through the payment of interest thereon and principal thereof in

B-5

accordance with their terms will provide money, or a combination of money and U.S. Government Obligations, in any event in an amount sufficient, without reinvestment, to pay all the principal of and any premium and interest on the Notes on the dates such payments are due in accordance with the terms of the Notes.

If an Event of Default shall occur and be continuing with respect to the Notes, the principal of and interest on the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modifications of the rights and obligations of the Company and the rights of the Noteholders under the Indenture at any time by the Company and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the outstanding Notes. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange therefor in lieu thereof whether or not notation of such consent or waiver is made upon the Note.

As set forth in and subject to the provisions of the Indenture, no Holder of any notes issued under the Indenture will have any right to institute any proceeding with respect to the Indenture or for any remedy thereunder unless such Holder shall have previously given to the Trustee written notice of a continuing Event of Default with respect to such Notes, the Holders of a majority in aggregate principal amount of the outstanding Notes of all series under the Indenture in respect of which on Event of Default has occurred and is continuing, considered as one class, shall have made written request and offered reasonable indemnity to the Trustee to institute such proceeding as Trustee and the Trustee shall have failed to institute such proceeding within 60 days; provided, however, that such limitations do not apply to a suit instituted by the Holder hereof for the enforcement of payment of the principal of and any premium or interest on this Note on or after the respective due dates expressed here.

No reference herein to the Indenture and to provisions of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, places and rates and the coin or currency prescribed in the Indenture.

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the Note register. Upon surrender of this Note for registration or transfer at the corporate trust office of the Trustee or such other office or agency as may be designated by the Company in the Borough of Manhattan, the City and State of New York, or St. Louis, Missouri, endorsed by or accompanied by a written instrument of transfer in form satisfactory to the Company and the Note registrar, duly executed by the Holder hereof or the attorney in fact of such Holder duly authorized in writing, one or more new Notes of this Series of like tenor and of authorized denominations and for the same aggregate principal amount will be issued to the designated transferee or transferees.

The Notes of this Series are issuable only in registered form, without coupons, in denominations of $100,000 and integral multiples of $1,000 thereof. As provided in the

B-6

Indenture and subject to certain limitations therein set forth, Notes of this Series are exchangeable for a like aggregate principal amount of Notes of this Series of like tenor and of a different authorized denomination, as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Note for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Note is registered as the owner thereof for all purposes, whether or not this Note is overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

The Indenture and the Notes shall be governed by, and construed in accordance with, the laws of the State of New York without regard to conflicts of law principles thereof.

All terms used in this Note that are defined in the Indenture shall have the meanings assigned to them in the Indenture.

B-7

ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this instrument, shall be construed as though they were written out in full according to applicable laws or regulations:

TEN COM -- as tenants in common           UNIF GIFT
                                          MIN ACT -   _____ Custodian ______
                                                      (Cust)         (Minor)
TEN ENT -- as tenants by the
entireties                                Under Uniform Gifts to Minors

JT TEN -- as joint tenants with right
 of survivorship and not as tenants in
 common                                   ______________________________
                                                       State

Additional abbreviations may also be used though not in the above list.


B-8

CERTIFICATE OF TRANSFER

AMEREN CORPORATION

5.70% Notes due February 1, 2007

FOR VALUE RECEIVED, the undersigned sells, assigns and transfers unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

Name and address of assignee must be printed or typewritten.

$

principal amount of beneficial interest in the referenced Security of the Company and does hereby irrevocably constitute and appoint

to transfer the said beneficial interest in such Security, with full power of substitution in the premises.

The undersigned certifies that said beneficial interest in said Security is being resold, pledged or otherwise transferred as follows:
(check one)

/ / to the Company;

/ / to a Person whom the undersigned reasonably believes is a qualified institutional buyer within the meaning of Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"), purchasing for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A;

/ / in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act;

/ / to an institution that is an "accredited investor" as defined in Rule
501(a)(1), (2), (3) or (7) under the Securities Act that is acquiring this Security for investment purposes and not for distribution (attach a copy of an Accredited Investor Certificate in the form annexed signed by an authorized officer of the transferee);

/ / as otherwise permitted by the non-registration legend appearing on this Security; or

/ / as otherwise agreed by the Company, confirmed in writing to the Trustee, as follows: [describe]

Dated:_________________             Signature:________________________

                                    NOTICE: The signature to this assignment
                                    must correspond with the name as written
                                    upon the face of the within instrument in
                                    every particular without alteration or
                                    enlargement, or any change whatever.

SIGNATURE GUARANTEE

Signatures must be guaranteed by an "eligible guarantor institution" meeting the requirement of the registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program ("STAMP") or such other "signature guarantee program" as may be determined by the registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.

B-9

[FORM OF INSTITUTIONAL ACCREDITED INVESTOR CERTIFICATE]

[Transferor Name and Address]

Ladies and Gentlemen:

In connection with our proposed purchase of 5.70% Notes due February 1, 2007 (the "Notes") issued by Ameren Corporation (the "Issuer"), we confirm that:

1. We have received a copy of the Offering Memorandum (the "Offering Memorandum") relating to the Notes and such other information as we deem necessary in order to make our investment decision. We acknowledge that we have read and agree to the matters stated under the caption NOTICE TO INVESTORS in such Offering Memorandum, and the restrictions on duplication or circulation of, or disclosure relating to, such Offering Memorandum.

2. We understand that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth in the Indenture relating to the Notes (the "Indenture") and that any subsequent transfer of the Notes is subject to certain restrictions and conditions set forth under NOTICE TO INVESTORS in the Offering Memorandum and the undersigned agrees to be bound by, and not to resell, pledge or otherwise transfer the Notes except in compliance with such restrictions and conditions and the Securities Act of 1933, as amended (the "Securities Act").

3. We understand that the offer and sale of the Notes have not been registered under the Securities Act, and that the Notes may not be offered or sold except as permitted in the following sentence. We agree, on our own behalf and on behalf of any accounts for which we are acting as hereinafter stated, that if we sell any Notes, we will do so only (A) to the Company, (B) so long as the Notes are eligible for resale pursuant to Rule 144A under the Securities Act ("Rule 144A"), to a person whom we reasonably believe is a "qualified institutional buyer" within the meaning of Rule 144A that purchases for its own account or for the account of a qualified institutional buyer to whom notice is given that the resale, pledge or other transfer is being made in reliance on Rule 144A, (C) to an institutional "accredited investor" (as defined below) that, prior to such transfer, furnishes to the Trustee (as defined in the Indenture) a signed letter containing certain representations and agreements relating to the restrictions on transfer of the Notes (substantially in the form of this letter), (D) in an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act, (E) pursuant to the exemption from registration provided by Rule 144 under the Securities Act (if available), or (F) in accordance with another applicable exemption from the registration requirements of, or in a transaction not subject to, the Securities Act or pursuant to an effective registration statement under the Securities Act, and we further agree to provide to any person purchasing any of the Notes from us a notice advising such purchaser that resales of the Notes are restricted as stated herein.

B-10

4. We understand that, on any proposed resale of any Notes, we will be required to furnish to the Trustee and the Issuer such certification and other information as the Trustee and the Issuer may reasonably require to confirm that the proposed sale complies with the foregoing restrictions. We further understand that the Notes purchased by us will bear a legend to the foregoing effect.

5. We are an institutional "accredited investor" (as defined in Rule
501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act) and have such knowledge and experience in financial and business matters as to be capable of evaluating the merits and risks of our investment in the Notes, and we and any accounts for which we are acting are each able to bear the economic risk of our or its investment.

6. We are acquiring the Notes purchased by us for our own account or for one or more accounts (each of which is an institutional "accredited investor") as to each of which we exercise sole investment discretion.

You, the Issuer and the Trustee are entitled to rely upon this letter and are irrevocably authorized to produce this letter or a copy hereof to any interested party in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby.

Very truly yours,

By:___________________________ Name:


Title:

B-11

EXHIBIT 5.1

January 30, 2002

Ameren Corporation
1901 Chouteau Avenue
St. Louis, Missouri 63103

Ladies and Gentlemen:

I am Vice President, General Counsel and Secretary of Ameren Corporation, a Missouri corporation (the "COMPANY"). The Company has filed with the Securities and Exchange Commission (the "COMMISSION") a Registration Statement on Form S-3 (the "REGISTRATION STATEMENT") with respect to up to $1,000,000,000 maximum aggregate offering price of (1) Senior Debt Securities (the "SENIOR DEBT SECURITIES") to be issued by the Company, (2) Subordinated Debt Securities (the "SUBORDINATED DEBT SECURITIES") to be issued by the Company, (3) Trust Preferred Securities to be issued by one or more Delaware business trusts (the "TRUST PREFERRED SECURITIES"), (4) the Company's guarantees (the "GUARANTEES") relating to such Trust Preferred Securities,
(5) Common Stock, $.01 par value (the "COMMON STOCK"), to be issued by the Company, (6) contracts to purchase shares of Common Stock (the "STOCK PURCHASE CONTRACTS") and (7) units, each comprised of a Stock Purchase Contract and either Senior Debt Securities or Subordinated Debt Securities, debt obligations of third parties (including U.S. Treasury securities) or Trust Preferred Securities, in each such case pledged to secure the holder's obligations to purchase Common Stock under the Stock Purchase Contract (the "STOCK PURCHASE UNITS" and, together with the foregoing securities, the "SECURITIES"), in each case, to be issued and sold from time to time pursuant to Rule 415 under the Securities Act of 1933, as amended (the "SECURITIES ACT").

The Senior Debt Securities will be issued pursuant to an Indenture dated as of December 1, 2001 between the Company and The Bank of New York, as trustee (the "SENIOR INDENTURE"), the Subordinated Debt Securities will be issued pursuant to an indenture and the trustee named therein (the "SUBORDINATED INDENTURE") and the Guarantees will be issued pursuant to one or more guarantee agreements between the Company and the trustee named therein (each, a "GUARANTEE AGREEMENT"), in each case as filed or in the respective forms filed or to be filed as exhibits to the Registration Statement.

In so acting, I have reviewed originals (or copies certified or otherwise identified to my satisfaction) of the Registration Statement (including the exhibits thereto), the Restated Articles of Incorporation and By-Laws of the Company as in effect on the date hereof, corporate and other documents, records and papers and certificates of public officials. I am a member of the Bar of the State of Missouri and, for purposes of this opinion, do not hold myself out as an expert of the laws of any jurisdiction other than the State of Missouri.


Ameren Corporation
January 30, 2002

On the basis of such review and assuming that (i) the applicable provisions of the Securities Act, the Trust Indenture Act of 1939, as amended, and the securities or "blue sky" laws of various states shall have been complied with, (ii) appropriate resolutions have been adopted by the Board of Directors of the Company (or a duly appointed committee or representative thereof) and
(iii) the applicable Securities have been issued and sold upon the terms specified in such resolutions and in any required orders of the Commission or other applicable regulatory approvals, I am of the opinion that:

1. When (i) the supplemental indenture or other instrument under the Senior Indenture to be entered into, or otherwise executed or adopted, in connection with the issuance of the Senior Debt Securities, (ii) the Subordinated Indenture and any supplemental indenture or other instrument thereunder to be entered into, or otherwise executed or adopted, in connection with the issuance of the Subordinated Debt Securities or (iii) the Guarantee Agreements, as applicable, have been duly executed and delivered by the proper officers of the Company and the trustees named therein, and when the Senior Debt Securities, the Subordinated Debt Securities and the Guarantees, as the case may be, have been duly executed, authenticated, delivered and paid for in accordance with the terms of the Senior Indenture, the Subordinated Indenture and the Guarantee Agreements, respectively, and on the terms and conditions set forth in the Registration Statement, the prospectus contained therein and the applicable supplement thereto, the Senior Debt Securities, the Subordinated Debt Securities and the Guarantees will be legally issued and will constitute the valid and binding obligations of the Company, subject to bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and other similar laws affecting creditors' rights, to general equitable principles (whether considered in a proceeding in equity or at law) and to an implied covenant of reasonableness, good faith and fair dealing.

2. When the Common Stock has been issued and sold on the terms and conditions set forth in the Registration Statement, the prospectus contained therein and the applicable supplement thereto and, if issued pursuant to Stock Purchase Contracts, Stock Purchase Units or warrants, in accordance with the terms thereof, and upon receipt by the Company of the full purchase price thereof, the Common Stock will be duly authorized, validly issued, fully paid and nonassessable.

3. When (i) the Stock Purchase Contracts or Stock Purchase Units have been issued and sold on the terms and conditions set forth in the Registration Statement, the prospectus contained therein and the applicable supplement thereto and (ii) the applicable purchase contract agreement and any related pledge agreement have been duly authorized, executed and delivered by the parties thereto, the Stock Purchase Contracts or Stock Purchase Units will be valid and binding obligations of the Company, subject to bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and other similar laws affecting creditors' rights, to general equitable principles (whether considered in a proceeding in equity or at law) and to an implied covenant of reasonableness, good faith and fair dealing.

2

Ameren Corporation
January 30, 2002

I hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the references to me under the headings "Legal Matters" in the related prospectus. In giving this consent, I do not thereby admit that I am within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission thereunder.

Very truly yours,

/s/ Steven R. Sullivan
--------------------------
Steven R. Sullivan
Vice President, General Counsel and Secretary

3

EXHIBIT 5.2

PILLSBURY WINTHROP LLP
ONE BATTERY PARK PLAZA
NEW YORK, NEW YORK 10004

January 30, 2002

Ameren Corporation
1901 Chouteau Avenue
St. Louis, Missouri 63103

Ladies and Gentlemen:

We have acted as New York counsel to Ameren Corporation, a Missouri corporation (the "COMPANY"), in connection with the filing by the Company with the Securities and Exchange Commission (the "COMMISSION") of the Registration Statement on Form S-3 (the "REGISTRATION STATEMENT") with respect to up to $1,000,000,000 maximum aggregate offering price of (1) Senior Debt Securities (the "SENIOR DEBT SECURITIES") to be issued by the Company, (2) Subordinated Debt Securities (the "SUBORDINATED DEBT Securities") to be issued by the Company, (3) Trust Preferred Securities to be issued by one or more Delaware business trusts (the "TRUST PREFERRED SECURITIES"), (4) the Company's guarantees (the "GUARANTEES") relating to the Trust Preferred Securities, (5) Common Stock, $.01 par value (the "COMMON STOCK"), to be issued by the Company, (6) contracts to purchase shares of Common Stock (the "STOCK PURCHASE CONTRACTS") and (7) units, each comprised of a Stock Purchase Contract and either Senior Debt Securities or Subordinated Debt Securities, debt obligations of third parties (including U.S. Treasury securities) or Trust Preferred Securities, in each such case pledged to secure the holder's obligations to purchase Common Stock under the Stock Purchase Contract (the "STOCK PURCHASE UNITS" and, together with the foregoing securities, the "SECURITIES"), in each case, to be issued and sold from time to time pursuant to Rule 415 under the Securities Act of 1933, as amended (the "SECURITIES ACT").

The Senior Debt Securities will be issued pursuant to an Indenture dated as of December 1, 2001 between the Company and The Bank of New York, as trustee (the "SENIOR INDENTURE"), the Subordinated Debt Securities will be issued pursuant to an indenture and the trustee named therein (the "SUBORDINATED INDENTURE") and the Guarantees will be issued pursuant to one or more guarantee agreements between the Company and the trustee named therein (each, a "GUARANTEE AGREEMENT"), in each case as filed or in the respective forms filed or to be filed as exhibits to the Registration Statement.


Ameren Corporation
January 30, 2002

In so acting, we have reviewed originals (or copies certified or otherwise identified to our satisfaction) of the Registration Statement (including the exhibits thereto), the Restated Articles of Incorporation and By-Laws of the Company as in effect on the date hereof, corporate and other documents, records and papers and certificates of public officials. We are members of the Bar of the State of New York and, for purposes of this opinion, do not hold ourselves out as experts of the laws of any jurisdiction other than the State of New York.

On the basis of such review and assuming that (i) the applicable provisions of the Securities Act, the Trust Indenture Act of 1939, as amended, and the securities or "blue sky" laws of various states shall have been complied with, (ii) appropriate resolutions have been adopted by the Board of Directors of the Company (or a duly appointed committee or representative thereof) and
(iii) the applicable Securities have been issued and sold upon the terms specified in such resolutions and in any required orders of the Commission or other applicable regulatory approvals, we are of the opinion that:

1. When (i) the supplemental indenture or other instrument under the Senior Indenture to be entered into, or otherwise executed or adopted, in connection with the issuance of the Senior Debt Securities, (ii) the Subordinated Indenture and any supplemental indenture or other instrument thereunder to be entered into, or otherwise executed or adopted, in connection with the issuance of the Subordinated Debt Securities or (iii) the Guarantee Agreements, as applicable, have been duly executed and delivered by the proper officers of the Company and the trustees named therein, and when the Senior Debt Securities, the Subordinated Debt Securities and the Guarantees, as the case may be, have been duly executed, authenticated, delivered and paid for in accordance with the terms of the Senior Indenture, the Subordinated Indenture and the Guarantee Agreements, respectively, and on the terms and conditions set forth in the Registration Statement, the prospectus contained therein and the applicable supplement thereto, the Senior Debt Securities, the Subordinated Debt Securities and the Guarantees will be legally issued and will constitute the valid and binding obligations of the Company, subject to bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and other similar laws affecting creditors' rights, to general equitable principles (whether considered in a proceeding in equity or at law) and to an implied covenant of reasonableness, good faith and fair dealing.

2. When (i) the applicable Trust has been duly created under the Business Trust Act of the State of Delaware, (ii) the Trust Agreement for such Trust has been duly executed and delivered by the proper officers of the Company, as sponsor, and the trustees of the Trust named therein and (iii) the Trust Preferred Securities of such Trust have been executed, delivered and paid for in accordance with the terms of such Trust Agreement and on the terms and conditions set forth in the Registration Statement, the prospectus contained therein and the applicable supplement thereto, the Trust Preferred Securities of such Trust will represent valid, fully paid and nonassessable undivided beneficial interests in the assets of such Trust. We note, however, that holders of such Trust Preferred Securities may be obligated to make payments as set forth in the related Trust Agreement.

2

Ameren Corporation
January 30, 2002

3. When (i) the Stock Purchase Contracts or Stock Purchase Units have been issued and sold on the terms and conditions set forth in the Registration Statement, the prospectus contained therein and the applicable supplement thereto and (ii) the applicable purchase contract agreement and any related pledge agreement have been duly authorized, executed and delivered by the parties thereto, the Stock Purchase Contracts or Stock Purchase Units will be valid and binding obligations of the Company, subject to bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and other similar laws affecting creditors' rights, to general equitable principles (whether considered in a proceeding in equity or at law) and to an implied covenant of reasonableness, good faith and fair dealing.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the references to us under the heading "Legal Matters" in the related prospectus. In giving this consent, we do not thereby admit that we are within the category of persons whose consent is required under
Section 7 of the Securities Act or the rules and regulations of the Commission thereunder.

Very truly yours,

Pillsbury Winthrop LLP

3

                                                                                                                          Exhibit 12

AMEREN CORPORATION

Ratio of Earnings to Fixed Charges

                                                                                                                      9 months ended
                                                               1996        1997        1998        1999        2000   Sept. 30, 2001
                                                               ----        ----        ----        ----        ----   --------------
EARNINGS (NUMERATOR):

Add:
Net income from continuing operations                         371,684     386,536     386,497     385,095     457,094     426,539
Income taxes                                                  253,710     243,667     265,598     253,490     298,623     289,859
Fixed charges                                                 212,414     209,527     206,191     193,151     204,631     167,231

Less:
Preference security dividend requirements
  of consolidated subsidiaries                                (28,554)    (20,432)    (21,195)    (20,977)    (20,997)    (15,773)

                                                             --------    --------    --------    --------    --------    --------
Total earnings                                                809,254     819,298     837,091     810,759     939,351     867,856
                                                             --------    --------    --------    --------    --------    --------


FIXED CHARGES (DENOMINATOR):

Interest expensed                                             180,402     185,368     181,580     168,275     179,706     148,836
Estimated interest costs within rental expense                  3,458       3,727       3,416       3,899       3,928       2,622

Preference security dividend requirements of
  consolidated subsidiaries:

     Preference dividends of consolidated subsidiaries         16,970      12,532      12,562      12,650      12,700       9,391
     Adjustment to pre-tax basis                               11,584       7,900       8,633       8,327       8,297       6,382
                                                             --------    --------    --------    --------    --------    --------
                                                               28,554      20,432      21,195      20,977      20,997      15,773

                                                             --------    --------    --------    --------    --------    --------
Total fixed charges                                           212,414     209,527     206,191     193,151     204,631     167,231
                                                             --------    --------    --------    --------    --------    --------


                                                             --------    --------    --------    --------    --------    --------
RATIO OF EARNINGS TO FIXED CHARGES                               3.81        3.91        4.06        4.20        4.59        5.19
                                                             --------    --------    --------    --------    --------    --------


EXHIBIT 23.3

CONSENT OF INDEPENDENT ACCOUNTANTS

We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated February 5, 2001 relating to the financial statements, which appears in the 2000 Annual Report to Shareholders, which is incorporated by reference in Ameren Corporation's Annual Report on Form 10-K for the year ended December 31, 2000. We also consent to the incorporation by reference of our report dated February 5, 2001 relating to the financial statement schedule, which appears in such Annual Report on Form 10-K. We also consent to the references to us under the headings "Experts" in such Registration Statement.

/s/  PricewaterhouseCoopers LLP
----------------------------------------
PricewaterhouseCoopers LLP
St. Louis, Missouri
January 30, 2002


Exhibit 24

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned William E. Cornelius hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 17th day of January, 2002.

                                          /s/ William E. Cornelius        (L.S.)
                              --------------------------------------------

STATE OF MISSOURI  )
                   ) SS.
CITY OF ST. LOUIS  )

On this 17th day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared William E. Cornelius, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                   /s/ K. A. Bell
----------------------------------------------
                    K. A. BELL
            Notary Public - Notary Seal
                STATE OF MISSOURI
                 St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Clifford L. Greenwalt hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 22nd day of January, 2002.

                                           /s/ Clifford L. Greenwalt      (L.S.)
                              --------------------------------------------

STATE OF MISSOURI  )
                   ) SS.
CITY OF ST. LOUIS  )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Clifford L. Greenwalt, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                   /s/ K. A. Bell
----------------------------------------------
                     K. A. BELL
              Notary Public - Notary Seal
                  STATE OF MISSOURI
                  St. Louis County
         My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Thomas A. Hays hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 16th day of January, 2002.

                                          /s/ Thomas A. Hays              (L.S.)
                              --------------------------------------------

STATE OF MISSOURI  )
                   ) SS.
CITY OF ST. LOUIS  )

On this 16th day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Thomas A. Hays, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                /s/ K. A. BELL
----------------------------------------------
                   K. A. BELL
           Notary Public - Notary Seal
                STATE OF MISSOURI
                St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Thomas H. Jacobsen hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 22nd day of January, 2002.

                                          /s/ Thomas H. Jacobsen          (L.S.)
                              --------------------------------------------

STATE OF MISSOURI  )
                   ) SS.
CITY OF ST. LOUIS  )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Thomas H. Jacobsen, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                 /s/ K. A. Bell
----------------------------------------------
                    K. A. BELL
             Notary Public - Notary Seal
                 STATE OF MISSOURI
                 St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Richard A. Liddy hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 17th day of January, 2002.

                                            /s/ Richard A. Liddy          (L.S.)
                              --------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 17th day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Richard A. Liddy, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                 /s/ K. A. Bell
----------------------------------------------
                   K. A. BELL
           Notary Public - Notary Seal
                STATE OF MISSOURI
                 St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Gordon R. Lohman hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 17th day of January, 2002.

                                         /s/ Gordon R. Lohman             (L.S.)
                              --------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 17th day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Gordon R. Lohman, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                 /s/ K. A. Bell
----------------------------------------------
                    K. A. BELL
           Notary Public - Notary Seal
                 STATE OF MISSOURI
                 St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Richard A. Lumpkin hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 21st day of January, 2002.

                                           /s/ Richard A. Lumpkin         (L.S.)
                              --------------------------------------------

STATE OF ILLINOIS )
                  ) SS.
CITY OF MATTOON   )

On this 21st day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Richard A. Lumpkin, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                 /s/ Sandra K. Oye
----------------------------------------------
                   Official Seal
                   Sandra K. Oye
           Notary Public State of Illinois
           My Commission Expires 02/22/05


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned John Peters MacCarthy hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 22nd day of January, 2002.

                                          /s/ John Peters MacCarthy       (L.S.)
                              --------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared John Peters MacCarthy, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                  /s/ K. A. Bell
----------------------------------------------
                    K. A. BELL
            Notary Public - Notary Seal
                 STATE OF MISSOURI
                 St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Hanne M. Merriman hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set her hand and seal this 23rd day of January, 2002.

             /s/ Hanne M. Merriman          (L.S.)
--------------------------------------------

DISTRICT OF COLUMBIA ) SS.

On this 23rd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Hanne M. Merriman, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that she executed the same as her free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

               /s/ Doris E. Osborne
----------------------------------------------
                 DORIS E. OSBORNE
                   Notary Public
           My Commission Expires 8-14-04


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Paul L. Miller, Jr. hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 22nd day of January, 2002.

                                        /s/ Paul L. Miller, Jr.          (L.S.)
                              -------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Paul L. Miller, Jr., known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                 /s/ K. A. Bell
----------------------------------------------
                   K. A. BELL
           Notary Public - Notary Seal
                STATE OF MISSOURI
                St. Louis County
      My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Harvey Saligman hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 22nd day of January, 2002.

                                         /s/ Harvey Saligman              (L.S.)
                              --------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Harvey Saligman, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

               /s/ K. A. Bell
----------------------------------------------
                 K. A. BELL
         Notary Public - Notary Seal
              STATE OF MISSOURI
               St. Louis County
     My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned Janet McAfee Weakley hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set her hand and seal this 22nd day of January, 2002.

                                        /s/ Janet M. Weakley              (L.S.)
                              -------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared Janet McAfee Weakley, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that she executed the same as her free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

              /s/ K. A. Bell
----------------------------------------------
                 K. A. BELL
          Notary Public - Notary Seal
              STATE OF MISSOURI
              St. Louis County
    My Commission Expires:  October 13, 2002


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS: That the undersigned James W. Wogsland hereby appoints Charles W. Mueller and/or Gary L. Rainwater and/or Warner L. Baxter and/or Steven R. Sullivan the true and lawful attorneys-in-fact of the undersigned, for and in the name, place and stead of the undersigned, to affix the name of the undersigned as a Director of Ameren Corporation to a Registration Statement on Form S-3 and any amendments thereto to be filed with the Securities and Exchange Commission under the Securities Act of 1933, covering new securities of Ameren Corporation in various forms, including senior debt securities, subordinated debt securities, trust preferred securities and related guarantees, common stock, stock purchase contracts and stock purchase units, as authorized by the Company's Executive Committee of the Board of Directors on January 16, 2002, and, for the performance of the same acts, each with power to appoint in his place and stead and as his substitute, one or more attorneys-in-fact for the undersigned, with full power of revocation; hereby ratifying and confirming all that said attorneys-in-fact may do by virtue hereof.
IN WITNESS WHEREOF, the undersigned has hereunto set his hand and seal this 22nd day of January, 2002.

                                           /s/ James W. Wogsland          (L.S.)
                              --------------------------------------------

STATE OF MISSOURI )
                  ) SS.
CITY OF ST. LOUIS )

On this 22nd day of January, 2002, before me, the undersigned Notary Public in and for said State, personally appeared James W. Wogsland, known to me to be the person described in and who executed the foregoing power of attorney and acknowledged to me that he executed the same as his free act and deed for the purposes therein stated.

IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed my official seal.

                 /s/ K. A. Bell
----------------------------------------------
                   K. A. BELL
           Notary Public - Notary Seal
                STATE OF MISSOURI
                 St. Louis County
      My Commission Expires:  October 13, 2002


EXHIBIT 25.1


FORM T-1
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

CHECK IF AN APPLICATION TO DETERMINE
ELIGIBILITY OF A TRUSTEE PURSUANT TO
SECTION 305(b)(2) |__|


THE BANK OF NEW YORK
(Exact name of trustee as specified in its charter)

New York                                           13-5160382
(State of incorporation                            (I.R.S. employer
if not a U.S. national bank)                       identification no.)

One Wall Street, New York, N.Y.                    10286
(Address of principal executive offices)           (Zip code)

                           ---------------------------

AMEREN CORPORATION
(Exact name of obligor as specified in its charter)

Missouri                                           43-1723446
(State or other jurisdiction of                    (I.R.S. employer
incorporation or organization)                     identification no.)

1901 Chouteau Avenue
St. Louis, Missouri                                63103
(Address of principal executive offices)           (Zip code)

                           ---------------------------

Senior Debt Securities
(Title of the indenture securities)



1. GENERAL INFORMATION. FURNISH THE FOLLOWING INFORMATION AS TO THE TRUSTEE:

(a) NAME AND ADDRESS OF EACH EXAMINING OR SUPERVISING AUTHORITY TO WHICH IT IS SUBJECT.


               Name                                    Address
---------------------------------------------------------------------------

      Superintendent of Banks of the        2 Rector Street, New York, N.Y.
      State of New York                     10006, and Albany, N.Y. 12203

      Federal Reserve Bank of New York      33 Liberty Plaza, New York, N.Y.
                                            10045

      Federal Deposit Insurance             Washington, D.C.  20429
      Corporation
      New York Clearing House               New York, New York   10005
      Association

      (b)   WHETHER IT IS AUTHORIZED TO EXERCISE CORPORATE TRUST POWERS.

      Yes.

2.    AFFILIATIONS WITH OBLIGOR.

IF THE OBLIGOR IS AN AFFILIATE OF THE TRUSTEE, DESCRIBE EACH SUCH
AFFILIATION.

None.

16. LIST OF EXHIBITS.

EXHIBITS IDENTIFIED IN PARENTHESES BELOW, ON FILE WITH THE COMMISSION, ARE INCORPORATED HEREIN BY REFERENCE AS AN EXHIBIT HERETO, PURSUANT TO RULE 7a-29 UNDER THE TRUST INDENTURE ACT OF 1939 (THE "ACT") AND 17 C.F.R. 229.10(d).

1. A copy of the Organization Certificate of The Bank of New York (formerly Irving Trust Company) as now in effect, which contains the authority to commence business and a grant of powers to exercise corporate trust powers. (Exhibit 1 to Amendment No. 1 to Form T-1 filed with Registration Statement No. 33-6215, Exhibits 1a and 1b to Form T-1 filed with Registration Statement No. 33-21672 and Exhibit 1 to Form T-1 filed with Registration Statement No. 33-29637.)

4. A copy of the existing By-laws of the Trustee. (Exhibit 4 to Form T-1 filed with Registration Statement No. 33-31019.)

6. The consent of the Trustee required by Section 321(b) of the Act.
(Exhibit 6 to Form T-1 filed with Registration Statement No. 33-44051.)

7. A copy of the latest report of condition of the Trustee published pursuant to law or to the requirements of its supervising or examining authority.

-2-

SIGNATURE

Pursuant to the requirements of the Act, the Trustee, The Bank of New York, a corporation organized and existing under the laws of the State of New York, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in The City of New York, and State of New York, on the 25th day of January, 2002.

THE BANK OF NEW YORK

By:     /s/ STACEY POINDEXTER
    --------------------------------
    Name:   STACEY POINDEXTER
    Title:  ASSISTANT TREASURER

-3-

EXHIBIT 7


Consolidated Report of Condition of

THE BANK OF NEW YORK

of One Wall Street, New York, N.Y. 10286
And Foreign and Domestic Subsidiaries,

a member of the Federal Reserve System, at the close of business September 30, 2001, published in accordance with a call made by the Federal Reserve Bank of this District pursuant to the provisions of the Federal Reserve Act.

                                                             Dollar Amounts
                                                              In Thousands
ASSETS
Cash and balances due from depository
  institutions:
  Noninterest-bearing balances and
   currency and coin..................                          $3,238,092
  Interest-bearing balances...........                           5,255,952
Securities:
  Held-to-maturity securities.........                             127,193
  Available-for-sale securities.......                          12,143,488
Federal funds sold and Securities

  purchased under agreements to resell                             281,677
Loans and lease financing receivables:
  Loans and leases held for sale......                                 786
  Loans and leases, net of unearned
   income...............46,206,726
  LESS: Allowance for loan and
   lease losses............607,115
  Loans and leases, net of unearned
   income and allowance...............                          45,599,611
Trading Assets........................                           9,074,924
Premises and fixed assets (including
  capitalized leases).................                             783,165
Other real estate owned...............                                 935
Investments in unconsolidated
  subsidiaries and associated
  companies...........................                             200,944
Customers' liability to this bank on
  acceptances outstanding.............                             311,521
Intangible assets.....................
   Goodwill...........................                           1,546,125
   Other intangible assets............                               8,497
Other assets..........................                           8,761,129
                                                                 ---------


Total assets..........................                         $87,334,039
                                                               ===========

LIABILITIES
Deposits:
  In domestic offices.................                         $28,254,986
  Noninterest-bearing.......10,843,829
  Interest-bearing..........17,411,157
  In foreign offices, Edge and
   Agreement subsidiaries, and IBFs...                          31,999,406
  Noninterest-bearing........1,006,193
  Interest-bearing..........30,993,213
Federal funds purchased and
  securities sold under agreements to
  repurchase..........................                           6,004,678
Trading liabilities...................                           2,286,940
Other borrowed money:
  (includes mortgage indebtedness and
  obligations under capitalized
  leases).......                                                 1,845,865
Bank's liability on acceptances
  executed and outstanding............                             440,362
Subordinated notes and debentures.....                           2,196,000
Other liabilities.....................                           7,606,565
                                                               -----------
Total liabilities.....................                         $80,634,802
                                                               ===========

EQUITY CAPITAL
Common stock..........................                           1,135,284
Surplus...............................                           1,050,729
Retained earnings.....................                           4,436,230
Accumulated other comprehensive income                              76,292
Other equity capital components.......                                   0
---------------------------------------------------------------------------
Total equity capital..................                           6,698,535
                                                               -----------
Total liabilities and equity capital..                         $87,334,039
                                                               ===========

I, Thomas J. Mastro, Senior Vice President and Comptroller of the above-named bank do hereby declare that this Report of Condition has been prepared in conformance with the instructions issued by the Board of Governors of the Federal Reserve System and is true to the best of my knowledge and belief.

Thomas J. Mastro, Senior Vice President and Comptroller

We, the undersigned directors, attest to the correctness of this Report of Condition and declare that it has been examined by us and to the best of our knowledge and belief has been


prepared in conformance with the instructions issued by the Board of Governors of the Federal Reserve System and is true and correct.

Thomas A. Renyi
Gerald L. Hassell
Alan R. Griffith Directors