2018

Notice of Annual Meeting

of Shareholders

and Proxy Statement

Thursday, May 3, 2018, 10:00 a.m. CDT

Peoria Civic Center, 201 SW Jefferson Ave., Peoria, Illinois 61602

Dear Fellow Shareholders:

You are cordially invited to attend Ameren Corporation’s 2018 Annual Meeting of Shareholders, which will be held at the Peoria Civic Center, 201 SW Jefferson Ave., Peoria, Illinois 61602, on Thursday, May 3, 2018, at 10:00 a.m. CDT. You can also listen to a live webcast of the meeting at www.amereninvestors.com.

At the meeting, I look forward to sharing with you information about our company’s strong, purpose-driven performance during 2017. Highlights include:

In keeping with our commitment to environmental stewardship, during the first quarter of 2019, we will publish a report dedicated to climate risk. The report will include analysis of the potential impacts of future policy and technology changes on our generation portfolio and will leverage the results of our participation in the Electric Power Research Institute’s study regarding utility industry scenario analyses with respect to climate change.

While I have highlighted our strong performance in 2017, it is important to note that our strategy is designed to deliver superior value not just for one year or five years into the future, but for decades to come. Executing our strategy will enable Ameren to address the rapid changes taking place in our industry, meet our customers’ rising energy needs and expectations, and deliver superior value to you, our shareholders.

Details for meeting attendance are included in this proxy statement. Also enclosed are details for how and when to vote and other important information. Your vote is very important, so please cast it promptly, even if you plan to attend the annual meeting.

Thank you for your strong support and confidence in our company.

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS OF AMEREN CORPORATION

To the Shareholders of Ameren Corporation:

We will hold the Annual Meeting of Shareholders of Ameren Corporation (the “Company”) at the Peoria Civic Center, 201 SW Jefferson Ave., Peoria, Illinois 61602, on Thursday, May 3, 2018, at 10:00 a.m. CDT, for the purposes of:

(1) electing 12 directors for terms ending at the annual meeting of shareholders to be held in 2019;

(2) providing a non-binding advisory vote to approve the compensation of our executives disclosed in the attached proxy statement;

(3) ratifying the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2018;

(4) considering a shareholder proposal regarding a report on coal combustion residuals, if presented at the meeting by the proponent; and

(5) acting on other proper business presented to the meeting.

The Board of Directors of the Company presently knows of no other business to come before the meeting.

If you owned shares of the Company’s Common Stock at the close of business on February 26, 2018, you are entitled to vote at the meeting and at any adjournment thereof. All shareholders are requested to be present at the meeting in person or by proxy so that a quorum may be assured.

On or about March 19, 2018, we will mail to certain of our shareholders a Notice of Internet Availability of Proxy Materials, which will indicate how to access our proxy materials on the Internet. By furnishing the Notice of Internet Availability of Proxy Materials, we are lowering the costs and reducing the environmental impact of our annual meeting.

Your prompt vote by proxy will reduce expenses. Please promptly submit your proxy by telephone, Internet or mail by following the instructions found on your Notice of Internet Availability of Proxy Materials or proxy card. If you attend the meeting, you may revoke your proxy by voting in person.

If you plan to attend the annual meeting of shareholders, please advise the Company in your proxy vote (by telephone or the Internet or, if you receive printed proxy materials, by checking the appropriate box on the proxy card) and bring the Admission Ticket on the reverse side of your proxy instruction card with you to the meeting. Persons without tickets will be admitted to the meeting upon verification of their shareholdings in the Company. If your shares are held in the name of your broker, bank or other nominee, you must bring an account statement or letter from the nominee indicating that you were the beneficial owner of the shares on February 26, 2018, the record date for voting. Please note that cameras and other recording devices will not be allowed in the meeting.

By order of the Board of Directors.

Gregory L. Nelson

Senior Vice President, General Counsel and Secretary

St. Louis, Missouri

March 19, 2018

TABLE OF CONTENTS

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Proxy Statement of Ameren Corporation

(First sent or given on or about March 19, 2018 to shareholders receiving written materials)

Principal Executive Offices:

One Ameren Plaza

1901 Chouteau Avenue

St. Louis, MO 63103

FORWARD-LOOKING INFORMATION

Statements in this proxy statement not based on historical facts are considered “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, Ameren Corporation (the “Company,” “Ameren,” “we,” “us” and “our”) is providing this cautionary statement to disclose that there are important factors that could cause actual results to differ materially from those anticipated. Reference is made to the 2017 Form 10-K for a list of such factors.

QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING AND VOTING

A.           The Annual Meeting of Shareholders of the Company (the “Annual Meeting”) will be held on Thursday, May 3, 2018, and at any adjournment thereof. Our Annual Meeting will be held at the Peoria Civic Center, 201 SW Jefferson Ave., Peoria, Illinois 61602, at 10:00 a.m. CDT. A map and directions to the Annual Meeting appear on the final page of this proxy statement.

A.           Only shareholders of record of our common stock, $0.01 par value (“Common Stock”), at the close of business on the record date, February 26, 2018, are entitled to vote at the Annual Meeting.

A.           1. Election of Directors.

  Twelve directors are to be elected at the Annual Meeting to serve until the next annual meeting of shareholders and until their respective successors have been duly elected and qualified.

  2. Non-Binding Advisory Approval of Executive Compensation.

  In accordance with Section 14A of the Exchange Act, the Company is providing shareholders with the right to cast a non-binding advisory vote at the Annual Meeting to approve the compensation of the NEOs. This proposal, commonly known as a “say-on-pay” proposal, provides shareholders with the opportunity to endorse or not endorse the Company’s compensation program.

  3. Ratification of the Appointment of PwC as Independent Registered Public Accounting Firm for the Fiscal Year Ending December 31, 2018.

  The Company is asking its shareholders to ratify the appointment of PwC as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2018. PwC was appointed by the Audit and Risk Committee.

Ameren Corporation  2018 Proxy Statement    7

  4. A Shareholder Proposal Regarding a Report on Coal Combustion Residuals.

  The Company is asking its shareholders to vote against a shareholder proposal regarding a report on coal combustion residuals, if presented at the meeting by the proponent.

A.           Each share of Common Stock is entitled to one vote. The shares referred to on your proxy card or Notice of Internet Availability of Proxy Materials represent all shares registered in the name(s) shown thereon, including shares held in our dividend reinvestment and stock purchase plan (“DRPlus Plan”) and Ameren’s 401(k) savings plan.

A.           As permitted by SEC rules, we are making this proxy statement and our annual report available to shareholders electronically via the Internet. On or about March 19, 2018, we began mailing to certain shareholders a Notice of Internet Availability of Proxy Materials containing instructions on how to access this proxy statement and our annual report and how to vote online. If you received that notice, you will not receive a printed copy of the proxy materials unless you request it by following the instructions for requesting such materials contained in the notice. The proxy statement and our 2017 Form 10-K, including consolidated financial statements, are available to you at www.amereninvestors.com/financial-info/proxy-materials/ameren-proxy-material.

  This proxy statement and the accompanying proxy card are also first being mailed to shareholders on or about March 19, 2018. In the same package with this proxy material, you should have received a copy of our 2017 Form 10-K, including consolidated financial statements. When you receive this package, if all of these materials are not included, please contact us and a copy of any missing material will be sent at no expense to you.

  You may reach us:

- by mail addressed to

Office of the Secretary

Ameren Corporation

P.O. Box 66149, Mail Code 1370

St. Louis, MO 63166-6149

- by calling toll-free 1-800-255-2237 (or in the St. Louis area 314-554-3502).

A.           In order to conduct the Annual Meeting, holders of more than one-half of the outstanding shares entitled to vote must be present in person or represented by proxy so that there is a quorum. The voting securities of the Company on February 26, 2018 consisted of 242,634,798 shares of Common Stock. Each share of Common Stock is entitled to one vote. It is important that you vote promptly so that your shares are counted toward the quorum.

  In determining whether a quorum is present at the Annual Meeting, shares represented by a proxy that directs that the shares abstain from voting or that a vote be withheld on a matter, as well as broker non-votes, will be deemed to be represented at the meeting for quorum purposes. A “broker non-vote” occurs when shares are represented by a proxy, returned by a broker, bank or other fiduciary holding shares as the record holder in nominee or “street” name for a beneficial owner, which gives voting instructions as to at least one of the matters to be voted on but indicates that the record holder does not have the authority to vote or give voting instructions by proxy on a particular matter, such as a non-discretionary matter for which voting instructions

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have not been given to the record holder by the beneficial owner. Shares as to which voting instructions are given as to at least one of the matters to be voted on will also be deemed to be so represented. If the proxy states how shares will be voted in the absence of instructions by the shareholder, such shares will be deemed to be represented at the meeting.

A.           In all matters, including the election of directors, every decision of a majority of the shares entitled to vote on the subject matter and represented in person or by proxy at the meeting at which a quorum is present will be valid as an act of the shareholders, unless a larger vote is required by law, the Company’s By-Laws or the Company’s Restated Articles of Incorporation. Each matter on the agenda for the Annual Meeting is subject to this majority voting standard.

  In tabulating the number of votes on a matter, (i) shares represented by a proxy, which directs that the shares abstain from voting or that a vote be withheld on one or more matters, will be deemed to be represented at the meeting as to such matter or matters, (ii) broker non-votes will not be deemed to be represented at the meeting for the purpose of the vote on such matter or matters, (iii) except as provided in (iv) below, shares represented by a proxy as to which voting instructions are not given as to one or more matters to be voted on will not be deemed to be represented at the meeting for the purpose of the vote as to such matter or matters and (iv) a proxy, which states how shares will be voted in the absence of instructions by the shareholder as to any matter, will be deemed to give voting instructions as to such matter. Shareholder votes are certified by independent inspectors of election.

A.           By Proxy. Before the Annual Meeting, you can give a proxy to vote your shares of the Company’s Common Stock in one of the following ways:

  The telephone and Internet voting procedures are designed to confirm your identity and to allow you to give your voting instructions. If you wish to vote by telephone or the Internet, please follow the instructions on your proxy card or Notice of Internet Availability of Proxy Materials. Additional instructions will be provided on the telephone message and website. Please have your proxy card or Notice of Internet Availability of Proxy Materials at hand when voting. If you vote by telephone or Internet, DO NOT mail a proxy card. The telephone and Internet voting facilities will close at 11:59 P.M. EDT on May 2, 2018.

If you mail us your properly completed and signed proxy card, or vote by telephone or the Internet, your shares of Common Stock will be voted according to the choices that you specify. If you sign and mail your proxy card without marking any choices, your proxy will be voted as recommended by the Board — FOR the Board’s nominees for director (Item (1)), FOR the non-binding advisory approval of the compensation of our NEOs disclosed in this proxy statement (Item (2)), FOR the ratification of the appointment of PricewaterhouseCoopers LLP as independent registered public accounting firm (Item (3)), AGAINST the shareholder proposal regarding a report on coal combustion residuals (Item (4)), and in the discretion of the named proxies upon such other matters as may properly come before the meeting.

  If you hold any shares in the 401(k) savings plan of Ameren, your completed proxy card or telephone or Internet proxy vote will serve as voting instructions to the plan trustee, and the plan trustee will vote your shares as you have directed. However, your voting instructions must be received at least five days prior to the Annual Meeting (i.e., by April 28, 2018) in order to count. In accordance with the terms of the plan, the trustee will vote all of the shares held in the plan for which voting instructions have not been received in accordance with instructions received from an independent fiduciary designated by Ameren Services Company, a wholly owned subsidiary of the Company (“Ameren Services”).

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  If you have shares registered in the name of a bank, broker or other registered owner or nominee, you should receive instructions from that registered owner about how to instruct them to vote those shares.

  In Person. You may come to the Annual Meeting and cast your vote there. Only shareholders of record at the close of business on the record date, February 26, 2018, are entitled to vote at and to attend the Annual Meeting.

A.           You may revoke your proxy at any time after you give it and before it is voted by entering a new vote by telephone or the Internet or by delivering either a written revocation or a signed proxy bearing a later date to the Secretary of the Company or by voting in person at the Annual Meeting. To revoke a proxy by telephone or the Internet, you must do so by 11:59 P.M. EDT on May 2, 2018 (following the directions on the proxy card or Notice of Internet Availability of Proxy Materials). Attendance at the Annual Meeting will not cause your previously granted proxy to be revoked unless you specifically so request.

A.           If you hold your shares in street name and you do not provide your broker with timely voting instructions, New York Stock Exchange (“NYSE”) rules permit brokerage firms to vote your shares at their discretion on certain “routine” matters. At the Annual Meeting, the only routine matter is the ratification of the appointment of PwC as our independent registered public accounting firm. Brokerage firms may not vote without instructions from you on the following matters: election of directors, advisory vote on approval of executive compensation, or the shareholder-presented proposal. Without your voting instruction on items that require them, a broker non-vote will occur.

A.           The solicitation of proxies is made by our Board of Directors (the “Board of Directors” or the “Board”) for the Annual Meeting of Shareholders of the Company. We are a holding company, and our principal direct and indirect subsidiaries include Union Electric Company, doing business as Ameren Missouri (“Ameren Missouri”); Ameren Illinois Company, doing business as Ameren Illinois (“Ameren Illinois”); and Ameren Transmission Company of Illinois.

A.           The Nominating and Corporate Governance Committee will consider director nominations from shareholders in accordance with the Company’s Policy Regarding Nominations of Directors (the “Director Nomination Policy”), a copy of which can be found on the Company’s website.

A.           An admission ticket is required to enter the Company’s Annual Meeting. Please follow the advance registration instructions on your Notice of Internet Availability of Proxy Materials or proxy card. Please plan to arrive promptly to have sufficient time to proceed through a customary security line, which may include a bag search.

A.           The Board of Directors has adopted a confidential shareholder voting policy for proxies, ballots and voting instructions submitted by shareholders. This policy does not prohibit disclosure when it is required by applicable law. In addition, nothing in the confidential shareholder voting policy prohibits shareholders or participants in the Company’s savings investment plans from voluntarily disclosing their votes or voting instructions, as applicable, to the Company’s directors or executive officers, nor does the policy prevent the

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Company or any agent of the Company from ascertaining which shareholders have voted or from making efforts to encourage shareholders to vote. The policy does not limit the free and voluntary communication between the Company and its shareholders. Except with respect to materials submitted regarding shares allocated to participant accounts in the Company’s savings investment plans, all comments written on proxies, ballots or voting materials, together with the names and addresses of the commenting shareholders, may be made available to Company directors and executive officers.

A.           The Annual Meeting will be webcast live on May 3, 2018. You are invited to visit www.amereninvestors.com at 10:00 a.m. CDT on May 3, 2018, to hear the webcast of the Annual Meeting. On the home page, you will click on “Live Webcast — 2018 Annual Meeting”, then the appropriate audio link. You cannot record your vote on this webcast.

A.           The names of shareholders of record entitled to vote at the Annual Meeting will be available at the Annual Meeting and, for ten days prior to the Annual Meeting, at the Office of the Secretary of the Company.

A.           The Company is permitted and intends to mail only one Notice of Internet Availability of Proxy Materials and/or one annual report and one proxy statement to multiple registered shareholders sharing an address who have consented to the delivery of one set of proxy materials per address or have received prior notice of our intent to do so, so long as the Company has not received contrary instructions from one or more of such shareholders. This practice is commonly referred to as “householding.” Householding reduces the volume of duplicate information received at your household and the cost to the Company of preparing and mailing duplicate materials.

  If you share an address with other registered shareholders and your household receives one set of the proxy materials and you decide you want a separate copy of the proxy materials, the Company will promptly mail your separate copy if you contact the Office of the Secretary, Ameren Corporation, P.O. Box 66149, St. Louis, Missouri 63166-6149 or by calling toll-free 1-800-255-2237 (or in the St. Louis area 314-554-3502). Additionally, to resume the mailing of individual copies of future proxy materials to a particular shareholder, you may contact the Office of the Secretary, and your request will be effective within 30 days after receipt. You may request householding of these documents by providing the Office of the Secretary with a written request to eliminate multiple mailings. The written request must include names and account numbers of all shareholders consenting to householding for a given address and must be signed by those shareholders.

  Additionally, the Company has been notified that certain banks, brokers and other nominees may household the Company’s proxy materials for shareholders who hold Company shares with the bank, broker or other nominee in “street” name and have consented to householding. In this case, you may request individual copies of proxy materials by contacting your bank, broker or other nominee.

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AMEREN CORPORATE GOVERNANCE OVERVIEW

The Company has a history of strong corporate governance practices and is continuously focused on ensuring that its corporate governance practices protect and enhance long-term shareholder value. The Company’s commitment to good corporate governance is demonstrated through practices such as:

Board of Directors:

Shareholder Rights:

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ITEMS YOU MAY VOTE ON

ITEM (1): ELECTION OF DIRECTORS

Twelve directors are to be elected at the Annual Meeting to serve until the next annual meeting of shareholders and until their respective successors have been duly elected and qualified. In the absence of instructions to the contrary, executed proxies will be voted in favor of the election of the persons listed below. In the event that any nominee for election as director should become unavailable to serve, votes will be cast for such substitute nominee or nominees as may be nominated by the Nominating and Corporate Governance Committee of the Board of Directors and approved by the Board of Directors, or the Board of Directors may reduce the size of the Board in accordance with the Company’s By-Laws and Restated Articles of Incorporation. The Board of Directors knows of no reason why any nominee will not be able to serve as director. The 12 nominees for director who receive the vote of at least a majority of the shares entitled to vote in the election of directors and represented in person or by proxy at the meeting at which a quorum is present will be elected. Shareholders may not cumulate votes in the election of directors. In the event that any nominee for reelection fails to obtain the required majority vote, such nominee will tender his or her resignation as a director for consideration by the Nominating and Corporate Governance Committee of the Board of Directors. The Nominating and Corporate Governance Committee will evaluate the best interests of the Company and its shareholders and will recommend to the Board the action to be taken with respect to any such tendered resignation. If there is a nominee, other than a nominee for reelection, who fails to obtain the required majority vote, such nominee will not be elected to the Board, and there will be a vacancy on the Board of Directors as a result thereof. Pursuant to the Company’s By-Laws and Restated Articles of Incorporation, any vacancy on the Board of Directors shall be filled by a majority of the directors then in office.

INFORMATION CONCERNING NOMINEES TO THE BOARD OF DIRECTORS

The nominees for our Board of Directors are listed below, along with their ages as of December 31, 2017, tenure as director, other directorships held by such nominee during the previous five years and business background for at least the last five years. Each nominee’s biography below also includes a description of the specific experience, qualifications, attributes or skills of each director or nominee that led the Board to conclude that such person should serve as a director of Ameren. The fact that we do not list a particular experience, qualification, attribute or skill for a director nominee does not mean that nominee does not possess that particular experience, qualification, attribute or skill. In addition to those specific experiences, qualifications, attributes or skills detailed below, each nominee has demonstrated the highest professional and personal ethics, a broad experience in business, government, education or technology, the ability to provide insights and practical wisdom based on their experience and expertise, a commitment to enhancing shareholder value, compliance with legal and regulatory requirements, and the ability to develop a good working relationship with other Board members and contribute to the Board’s working relationship with senior management of the Company. In assessing the composition of the Board of Directors, the Nominating and Corporate Governance Committee recommends Board nominees so that, collectively, the Board is balanced by having the necessary experience, qualifications, attributes and skills and that no nominee is recommended because of one particular criterion, except that the Nominating and Corporate Governance Committee does believe it appropriate for at least one member of the Board to meet the criteria for an “audit committee financial expert” as defined by SEC rules. See “— CORPORATE GOVERNANCE — Consideration of Director Nominees” below for additional information regarding director nominees and the nominating process.

Each nominee has consented to being nominated for director and has agreed to serve if elected. No arrangement or understanding exists between any nominee and the Company or, to the Company’s knowledge, any other person or persons pursuant to which any nominee was or is to be selected as a director or nominee. All of the nominees are currently directors of the Company and, except for Mr. Ivey, all of the nominees were elected by shareholders at the Company’s prior annual meeting. There are no family relationships between any director, executive officer, or person nominated or chosen by the Company to become a director or executive officer. All of the nominees for election to the Board were unanimously recommended by the Nominating and Corporate Governance Committee of the Board of Directors and were unanimously nominated by the Board of Directors. In addition, Mr. Ivey was recommended by a third-party search firm retained by the Nominating and Corporate Governance Committee prior to his nomination and election as a director.

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WARNER L. BAXTER

		CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE OFFICER OF THE COMPANY   Director since: 2014   Age: 56		Outside directorships: •  U.S. Bancorp, December 2015 — Present   •  UMB Financial Corporation, 2013 — October 2015

EXECUTIVE EXPERIENCE:

Mr. Baxter began his career with Ameren Missouri in 1995 as Assistant Controller. He was named Controller of Ameren Missouri in 1996. Following the 1997 merger of Ameren Missouri and CIPSCO Incorporated, he served as Vice President and Controller of Ameren and Ameren Services. In 2001, Mr. Baxter was named Senior Vice President, Finance. From 2003 to 2009, Mr. Baxter was Executive Vice President and Chief Financial Officer of Ameren and certain of its subsidiaries, where he led the finance, strategic planning and enterprise risk management functions. From 2007 to 2009, he was also President and Chief Executive Officer of Ameren Services. From 2009 to 2014, Mr. Baxter served as the Chairman, President and Chief Executive Officer of Ameren Missouri. On February 14, 2014, Mr. Baxter succeeded Thomas R. Voss as President of the Company. Mr. Baxter succeeded Mr. Voss as Chief Executive Officer of the Company on April 24, 2014 and as Chairman of the Board on July 1, 2014. Prior to joining Ameren, Mr. Baxter served as senior manager in PwC’s national office in New York City from 1993 to 1995. From 1983 to 1993, Mr. Baxter worked in PwC’s St. Louis office, where he provided auditing and consulting services to clients in a variety of industries.

Mr. Baxter served as a director of Ameren Missouri from 1999 to 2014, and as a director of Ameren Illinois from 1999 to 2009.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Baxter’s extensive executive management and leadership experience; strong strategic planning, regulatory, accounting, financial, industry, risk management, government relations, operations and compensation skills and experience; tenure with the Company (and its current and former affiliates); and tenure and contributions as a current Board member, the Board concluded that Mr. Baxter should serve as a director of Ameren.

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CATHERINE S. BRUNE

		RETIRED PRESIDENT, ALLSTATE PROTECTION EASTERN TERRITORY OF ALLSTATE INSURANCE COMPANY   Director since: 2011   Age: 64		Standing Board committees: •  Audit and Risk Committee   •  Nominating and Corporate Governance Committee   Outside directorships: None

EXECUTIVE EXPERIENCE:

Ms. Brune served as President of Allstate, a personal lines insurer, from October 2010 to November 2013 and oversaw Property/Casualty operations in 23 states and Canada. Ms. Brune worked in various managerial capacities for Allstate from 1976 to 2013. She was elected the company’s youngest officer in 1986, moving into information technology in the early 1990s. In 2002, Ms. Brune was named Allstate’s Senior Vice President, Chief Information Officer. Ms. Brune was a member of Allstate’s senior leadership team. Ms. Brune retired from Allstate in November 2013.

SKILLS AND QUALIFICATIONS:

Based primarily upon Ms. Brune’s extensive executive management and leadership experience as a former President and Chief Information Officer of a leading insurance company; strong information and technology, strategic planning, financial, regulatory, compensation, operations, customer relations, risk management and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Ms. Brune should serve as a director of Ameren.

J. EDWARD COLEMAN

		FORMER CHIEF EXECUTIVE OFFICER OF CIOX HEALTH   Director since: 2015   Age: 66		Standing Board committees: •  Audit and Risk Committee   •  Nuclear and Operations Committee   Outside directorships: •  Lexmark International, Inc., 2010–2016   •  Unisys Corporation, 2008–2014

EXECUTIVE EXPERIENCE:

Mr. Coleman served as the Chief Executive Officer of CIOX Health, a health information management firm, from May 2016 to June 2017. Mr. Coleman served as Chairman and Chief Executive Officer of Unisys Corporation from October 2008 to December 2014. He previously served as Chief Executive Officer of Gateway, Inc. from 2006 to 2008, as Senior Vice President and President of Enterprise Computing Solutions at Arrow Electronics from 2005 to 2006, and as Chief Executive Officer of CompuCom Systems, Inc. from 1999 to 2004 and as Chairman of the Board from 2001 to 2004. Earlier in his career, he held various leadership positions at Computer Sciences Corporation and IBM Corporation.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Coleman’s extensive executive management and leadership experience as a former chief executive officer of both private and publicly traded technology companies; strong strategic planning, financial, information technology, customer relations, compensation, operations and administrative skills and experience; and contributions as a current Board and Board committee member, the Board concluded that Mr. Coleman should serve as a director of Ameren.

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ELLEN M. FITZSIMMONS

		CORPORATE EXECUTIVE VICE PRESIDENT, GENERAL COUNSEL AND CORPORATE SECRETARY OF SUNTRUST BANKS, INC.   Director since: 2009   Age: 57		Standing Board committees: •  Finance Committee   •  Nuclear and Operations Committee   Outside directorships: None

EXECUTIVE EXPERIENCE:

Ms. Fitzsimmons serves as the Corporate Executive Vice President, General Counsel and Corporate Secretary of SunTrust Banks, Inc. From 2003 to November 2017, Ms. Fitzsimmons served as Executive Vice President of Law and Public Affairs, General Counsel and Corporate Secretary of CSX Corporation, a transportation supplier, which she first joined in 1991. Ms. Fitzsimmons oversaw all legal, government relations and public affairs activities for CSX. During Ms. Fitzsimmons’ tenure with CSX, her responsibilities included key roles in major risk and corporate governance-related areas.

SKILLS AND QUALIFICATIONS:

Based primarily upon Ms. Fitzsimmons’ extensive executive and leadership experience as the Executive Vice President, General Counsel and Corporate Secretary of a financial services provider and of a transportation supplier; strong legal, government relations, public affairs, regulatory, accounting, financial, risk management, internal audit, compliance, corporate governance, compensation and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Ms. Fitzsimmons should serve as a director of Ameren.

RAFAEL FLORES

		FORMER SENIOR VICE PRESIDENT AND CHIEF NUCLEAR OFFICER OF LUMINANT   Director since: 2015   Age: 62		Standing Board committees: •  Nominating and Corporate Governance Committee   •  Nuclear and Operations Committee   Outside directorships: None

EXECUTIVE EXPERIENCE:

Mr. Flores joined Luminant, a private Texas-based electric utility, in 1983 and served as Senior Vice President and Chief Nuclear Officer from 2009 to 2015. In this position, he oversaw operations at the Comanche Peak Nuclear Power Plant in Texas, reported nuclear matters directly to Luminant’s nuclear oversight advisory board and represented Luminant with the Nuclear Regulatory Commission, the Institute of Nuclear Power Operations, the Nuclear Energy Institute and on various committees and working groups in the nuclear industry.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Flores’ extensive executive and leadership experience as Senior Vice President and Chief Nuclear Officer of an electric utility; government relations, public affairs, regulatory, industry, risk management, compensation, operations and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Mr. Flores should serve as a director of Ameren.

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WALTER J. GALVIN

		RETIRED VICE CHAIRMAN AND CHIEF FINANCIAL OFFICER OF EMERSON ELECTRIC CO.   Director since: 2007   Lead Director since: 2013   Age: 71		Standing Board committees: •  Audit and Risk Committee (Chair)   •  Finance Committee   Outside directorships: •  Aegion Corporation, 2014–Present   •  Emerson Electric Co., 2000–2013   •  F.M. Global Insurance Company (non-reporting company), 1995–2015

EXECUTIVE EXPERIENCE:

Mr. Galvin serves as a senior advisor to Irving Place Capital, a private equity fund. Mr. Galvin served as Vice Chairman of Emerson Electric, an electrical and electronics manufacturer, from October 2009 to February 2013. He served as Emerson Electric’s Chief Financial Officer from 1993 until February 2010. He served as a management member of Emerson Electric’s Board of Directors from 2000 to February 2013 and as a consultant to Emerson Electric from February 2013 to September 2015.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Galvin’s extensive executive management and leadership experience as the former Vice Chairman and Chief Financial Officer of an industrial manufacturing company; significant accounting, financial, risk management, regulatory, industry, compensation and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Mr. Galvin should serve as a director of Ameren.

RICHARD J. HARSHMAN

		CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE OFFICER OF ALLEGHENY TECHNOLOGIES INCORPORATED   Director since: 2013   Age: 61   Mr. Harshman will succeed Mr. Galvin as Lead Director, effective May 3, 2018.		Standing Board committees: •  Human Resources Committee   •  Nuclear and Operations Committee (Chair)   Outside directorships: •  Allegheny Technologies Incorporated, 2011–Present

EXECUTIVE EXPERIENCE:

Mr. Harshman serves as the Chairman, President and Chief Executive Officer of Allegheny Technologies Incorporated, a producer of specialty materials and components to the global electrical energy, aerospace and defense, oil and gas, chemical process industry, medical, and other diversified consumer and durable goods markets.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Harshman’s extensive executive management and leadership experience as the Chairman, President and Chief Executive Officer, and previously Chief Financial Officer, of a specialty materials manufacturer; his significant strategic planning, financial, operations, regulatory, industry, customer relations, compensation and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Mr. Harshman should serve as a director of Ameren.

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CRAIG S. IVEY

		RETIRED PRESIDENT OF CONSOLIDATED EDISON COMPANY OF NEW YORK, INC.   Director since: 2018   Age: 55		Standing Board committees: •  Audit and Risk Committee   •  Nuclear and Operations Committee   Outside directorships: None

EXECUTIVE EXPERIENCE:

Mr. Ivey served as President of Consolidated Edison Company of New York, Inc. (Con Edison) from 2009 through 2017. Con Edison provides electric service to approximately 3.4 million customers and delivers gas to approximately 1.1 million customers in New York City and Westchester County; it also operates the largest steam distribution system in the United States for customers in New York City. He previously served in various positions at Dominion Resources, an electric utility company in Virginia, from 1985 to 2009, most recently as Senior Vice President for Transmission and Distribution.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Ivey’s extensive executive management and leadership experience as the President and Senior Vice President of regulated utility companies and his significant strategic planning, regulatory, industry, risk management, government relations, operations, and customer relations skills and experience, the Board concluded that Mr. Ivey should serve as a director of Ameren.

GAYLE P.W. JACKSON, PH.D.

		PRESIDENT AND CHIEF EXECUTIVE OFFICER, ENERGY GLOBAL, INC.   Director since: 2005   Age: 71		Standing Board committees: •  Nominating and Corporate Governance Committee (Chair)   •  Nuclear and Operations Committee   Outside directorships: •  Atlas Pipeline Partners, L.P., 2005–2009, 2011–2015

EXECUTIVE EXPERIENCE:

Dr. Jackson serves as the President and Chief Executive Officer of Energy Global, Inc., a consulting firm that specializes in corporate development, diversification and government relations strategies for energy companies. From 2002 to 2004, Dr. Jackson served as Managing Director of FE Clean Energy Group, a global private equity management firm that invests in energy companies and projects in Central and Eastern Europe, Latin America and Asia. Dr. Jackson is a past Deputy Chairman of the Federal Reserve Bank of St. Louis.

SKILLS AND QUALIFICATIONS:

Based primarily upon Dr. Jackson’s extensive executive management and leadership experience as the President and Chief Executive Officer of a consulting firm which specializes in corporate development, diversification and government relations strategies for energy companies; strong strategic planning, marketing, banking, financial, regulatory, industry, compensation and administrative skills and experience; her experience as a director of two other publicly-traded companies; and tenure and contributions as a current Board and Board committee member, the Board concluded that Dr. Jackson should serve as a director of Ameren.

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JAMES C. JOHNSON

		RETIRED GENERAL COUNSEL, LOOP CAPITAL MARKETS LLC   Director since: 2005   Age: 65		Standing Board committees: •  Human Resources Committee (Chair)   •  Nominating and Corporate Governance Committee   Outside directorships: •  Hanesbrands Inc., 2006–Present   •  Energizer Holdings, Inc., 2013–Present   •  Edgewell Personal Care Company, 2015–Present

EXECUTIVE EXPERIENCE:

Mr. Johnson served as General Counsel of Loop Capital Markets LLC, a financial services firm, from November 2010 to December 2013. From 1998 until 2009, Mr. Johnson served in a number of responsible positions at The Boeing Company, an aerospace and defense firm, including serving as Vice President, Corporate Secretary and Assistant General Counsel from 2003 until 2007 and as Vice President and Assistant General Counsel, Commercial Airplanes, from 2007 until his retirement in March 2009.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Johnson’s extensive executive management and leadership experience as the former General Counsel of a financial services firm and as the former Vice President, Corporate Secretary and Assistant General Counsel of an aerospace and defense firm; his strong legal, compliance, risk management, board-management relations, corporate governance, finance, regulatory and compensation skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Mr. Johnson should serve as a director of Ameren.

STEVEN H. LIPSTEIN

		FORMER PRESIDENT AND CHIEF EXECUTIVE OFFICER OF BJC HEALTHCARE   Director since: 2010   Age: 61		Standing Board committees: •  Human Resources Committee   •  Finance Committee   Outside directorships: •  BJC HealthCare (non-profit organization), 1999–2017

EXECUTIVE EXPERIENCE:

Mr. Lipstein served as President and Chief Executive Officer of BJC HealthCare, one of the largest non-profit healthcare organizations in the United States, from 1999 through 2016, and as Chief Executive Officer through December 2017. From 1982 to 1999, Mr. Lipstein held various executive positions within The University of Chicago Hospitals and Health System and The Johns Hopkins Hospital and Health System. Mr. Lipstein served as Chairman of the Federal Reserve Bank of St. Louis from 2009 to 2011.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Lipstein’s extensive executive management and leadership experience as the Chief Executive Officer and former President of a healthcare organization; strong strategic planning, banking, regulatory, financial, customer relations, operations, compensation and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Mr. Lipstein should serve as a director of Ameren.

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STEPHEN R. WILSON

		RETIRED CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE OFFICER OF CF INDUSTRIES HOLDINGS, INC.   Director since: 2009   Age: 69		Standing Board committees: •  Finance Committee (Chair)   •  Human Resources Committee   Outside directorships: •  CF Industries Holdings, Inc., 2005–2014   •  Terra Nitrogen GP, Inc., 2010–2014   •  GATX Corporation, 2014–Present   •  Keytrade AG, 2016–Present

EXECUTIVE EXPERIENCE:

Mr. Wilson is the retired Chairman, President and Chief Executive Officer of CF Industries Holdings, Inc., a manufacturer and distributor of nitrogen fertilizer products. He served in those capacities from 2005 until his retirement in 2014, as President and Chief Executive Officer of CF Industries, Inc. (a predecessor company) from 2003 to 2005 and as Chief Financial Officer from 1991 to 2003.

SKILLS AND QUALIFICATIONS:

Based primarily upon Mr. Wilson’s extensive executive management and leadership experience as the former Chairman, President and Chief Executive Officer and the former Chief Financial Officer of an industrial manufacturing company; strong strategic planning, financial, operations, risk management, regulatory, compensation, customer relations and administrative skills and experience; and tenure and contributions as a current Board and Board committee member, the Board concluded that Mr. Wilson should serve as a director of Ameren.

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BOARD STRUCTURE

Board and Committee Meetings and Annual Meeting Attendance

During 2017, the Board of Directors met 6 times. All then-incumbent directors attended or participated in 75 percent or more of the aggregate number of meetings of the Board and the Board Committees of which they were members held during the period for which such directors have been directors.

The Company has adopted a policy under which Board members are expected to attend each shareholders’ meeting. At the 2017 annual meeting of shareholders, all of the then-incumbent directors were in attendance.

Director Qualification Standards

The Board of Directors, in accordance with NYSE listing standards, has adopted a formal set of Corporate Governance Guidelines, which include certain director qualification standards.

A director who attains age 72 prior to the date of an annual meeting is required to submit a letter to the Nominating and Corporate Governance Committee offering his or her resignation from the Board, effective with the end of the director’s elected term, for consideration by the Nominating and Corporate Governance Committee. The Nominating and Corporate Governance Committee will review the appropriateness of continued service on the Board of Directors by that director and make a recommendation to the Board of Directors and, if applicable, repeat such review annually thereafter.

In addition, the Corporate Governance Guidelines provide that a director who undergoes a significant change with respect to principal employment is required to notify the Nominating and Corporate Governance Committee and offer his or her resignation from the Board. The Nominating and Corporate Governance Committee will then evaluate the facts and circumstances and make a recommendation to the Board whether to accept the offered resignation or request that the director continue to serve on the Board.

Board Diversity

Board Leadership Structure

The Company’s By-Laws and Corporate Governance Guidelines delegate to the Board of Directors the right to exercise its discretion to either separate or combine the offices of Chairman of the Board and Chief Executive Officer. The Board annually considers the appropriate leadership structure for the Company and has concluded that the Company and its shareholders are best served by the Board retaining discretion to determine whether the same individual should serve as both Chairman of the Board and Chief Executive Officer. This decision is based upon the Board’s determination of what is in the best interests of the Company and its shareholders, in light of then-current and anticipated future circumstances and taking into consideration succession planning, skills and experience of the individual(s) filling those positions, and other relevant factors. The independent members of the Board have determined that the Board leadership structure that is most appropriate at this time, given the specific characteristics and circumstances of the Company and the skills and experience of Mr. Baxter, is a leadership structure that combines the roles of Chairman of the Board and Chief Executive Officer with Mr. Baxter filling those roles for the following primary reasons:

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Age Gender Race/Ethnicity Tenure

The Board recognizes that, depending on the specific characteristics and circumstances of the Company, other leadership structures might also be appropriate. A Board leadership structure that separates the roles of Chairman of the Board and Chief Executive Officer has previously served the Company and its shareholders well and may serve them well in the future. The Company is committed to reviewing this determination on an annual basis.

According to the Company’s Corporate Governance Guidelines, when the Chairman of the Board is the Chief Executive Officer or an employee of the Company, the Nominating and Corporate Governance Committee of the Board of Directors will select an independent director to preside at or lead the executive sessions (which selection will be ratified by vote of the independent directors of the Board of Directors) (the “Lead Director”). The Company’s Corporate Governance Guidelines provide that the Lead Director will serve a one-year term and that it is expected that the Lead Director will serve at least three and no more than five consecutive terms in order to facilitate the rotation of the Lead Director position while maintaining experienced leadership. Effective May 3, 2018, Mr. Harshman will succeed Mr. Galvin as the Lead Director. The Company’s Corporate Governance Guidelines set forth the authority, duties and responsibilities of the Board of Directors’ Lead Director as follows:

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In performing the duties described above, the Lead Director is expected to consult with the Chairs of the appropriate Board committees and solicit their participation. The Lead Director also performs such other duties as may be assigned to the Lead Director by the Company’s By-Laws or the Board of Directors.

Risk Oversight Process

Given the importance of monitoring risks, the Board has charged its Audit and Risk Committee with oversight responsibility of the Company’s overall enterprise risk management process, which includes the identification, assessment, mitigation and monitoring of risks on a Company-wide basis. Our enterprise risk management program is a comprehensive, consistently applied management framework that is designed to ensure all forms of risk and opportunity are identified, reported and managed in an effective manner. Risk management is embedded into business processes and key decision making at all levels of the Company.

The Audit and Risk Committee meets on a regular basis to review the enterprise risk management processes, at which time applicable members of senior management provide reports to the Audit and Risk Committee. The Audit and Risk Committee coordinates this oversight with other committees of the Board having primary oversight responsibility for specific risks (see “— BOARD COMMITTEES” below). Each of the Board’s standing committees receives regular reports from members of senior management concerning its assessment of Company risks within the purview of such committee. Each such committee also has the authority to engage independent advisers. The risks that are not specifically assigned to a Board committee are considered by the Audit and Risk Committee through its oversight of the Company’s enterprise risk management process. The Audit and Risk Committee then discusses with members of senior management methods to mitigate such risks.

Notwithstanding the Board’s oversight delegation to the Audit and Risk Committee, the entire Board is actively involved in risk oversight. The Audit and Risk Committee annually reviews for the Board which committees maintain oversight responsibilities described above and the overall effectiveness of the enterprise risk management process. In addition, at each of its meetings, the Board receives a report from the Chair of the Audit and Risk Committee, as well as from the Chair of each of the Board’s other standing committees identified below, each of which is currently chaired by an independent director. The Board then discusses and deliberates on the Company’s risk management practices. Through the process outlined above, the Board believes that its leadership structure provides effective oversight of the Company’s risk management.

Consideration of Risks Associated with Environmental, Social and Governance Matters

We are committed to operating in a sustainable manner and are doing this by carefully balancing our key responsibilities to our customers and the communities we serve, our co-workers, our shareholders, and the environment. Reflecting this balanced approach to sustainability, Ameren’s commitment to strong corporate governance includes policies and principles that integrate environmental, social and governance (“ESG”) matters into our broader risk management and strategic planning initiatives. We are focused on ensuring that our corporate governance and enterprise risk management practices protect and enhance long-term shareholder value and reflect our environmental stewardship.

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The full Board of Directors oversees environmental matters as they relate to policy and strategy. The Nuclear and Operations Committee oversees and reviews our operations, including safety, performance, and compliance issues, including environmental and nuclear compliance, and related risk management policies and practices. The Nominating and Corporate Governance Committee oversees governance matters and public affairs considerations with respect to key constituents, including the responsiveness of the Company’s positions on shareholder proposals for inclusion in the proxy statement. The Human Resources Committee is responsible for oversight of our programs to attract, develop, promote and retain a diverse and inclusive workforce and to ensure that these programs support our overall business strategy and objectives.

We provide extensive information regarding our sustainability initiatives through our website, including in our annual Corporate Social Responsibility report, our responses to the annual climate change and water surveys conducted by the Carbon Disclosure Project, and our other filings with the SEC. In addition, we are participating in the Edison Electric Institute’s (“EEI”) ESG and sustainability-related pilot reporting program. This program aims to develop a reporting framework to enable utility companies to provide key ESG and sustainability information on a consistent basis. EEI’s pilot reporting framework includes both a quantitative section with data on recent greenhouse gas emissions, as well as a 2005 baseline for comparison, and a qualitative section with a discussion of the company’s ESG and sustainability strategy and governance. Our pilot report under this framework, which includes emissions data for 2015 and 2016, was published in March 2018 and is available on our website at www.amereninvestors.com/corporate-governance/EEI-ESG-Sustainability. EEI expects to release an updated version of the reporting framework in 2018 for member company use in reporting 2017 data.

During the first quarter of 2019, we will issue a climate risk report that includes analysis of the impact of technological and policy changes that are consistent with limiting global warming. Among other things, this report will leverage the results of our participation in the Electric Power Research Institute’s study regarding utility industry scenario analyses with respect to climate change, which is expected to be complete in late 2018.

Consideration of Risks Associated with Compensation

In evaluating the material elements of compensation available to executives and other Company employees, the Human Resources Committee takes into consideration whether the Company’s compensation policies and practices may incentivize behaviors that might lead to excessive risk taking. The Human Resources Committee, with the assistance of its independent compensation consultant, Meridian Compensation Partners, LLC (“Meridian”), and Company management, reviews the Company’s compensation policies and practices each year for design features that have the potential to encourage excessive risk taking. The program contains multiple design features that manage or mitigate these potential risks, including:

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Based upon the above considerations, the Human Resources Committee determined that the Company’s compensation policies and practices are not reasonably likely to have a material adverse effect on the Company.

BOARD COMMITTEES

The Board of Directors has a standing Audit and Risk Committee, Human Resources Committee, Nominating and Corporate Governance Committee, Nuclear and Operations Committee and Finance Committee, the chairs and members of which are recommended by the Nominating and Corporate Governance Committee, appointed annually by the Board and are identified below. The Audit and Risk Committee, Human Resources Committee and Nominating and Corporate Governance Committee are comprised entirely of non-management directors, each of whom the Board of Directors has determined to be “independent” as defined by the relevant provisions of the Sarbanes-Oxley Act of 2002, the NYSE listing standards and the Director Nomination Policy. In addition, the Nuclear and Operations Committee and the Finance Committee are currently comprised entirely of non-management directors, each of whom the Board has also determined to be “independent” under the Director Nomination Policy. A more complete description of the duties of each standing Board committee is contained in each standing Board committee’s charter available at www.amereninvestors.com/corporate-governance.

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CORPORATE GOVERNANCE

Corporate Governance Guidelines and Policies, Committee Charters and Codes of Conduct

The Board of Directors has adopted Corporate Governance Guidelines, a Director Nomination Policy, a Policy Regarding Communications to the Board of Directors, a Related Person Transactions Policy and written charters for its Audit and Risk Committee, Human Resources Committee, Nominating and Corporate Governance Committee, Nuclear and Operations Committee and Finance Committee. The Board of Directors also has adopted the Company’s code of business conduct (referred to as Ameren’s Principles of Business Conduct) applicable to all of the Company’s directors, officers and employees, and the Company’s Code of Ethics for Principal Executive and Senior Financial Officers. These documents and other items relating to the governance of the Company can be found on our website at www.amereninvestors.com/corporate-governance. These documents are also available in print free of charge to any shareholder who requests them from the Office of the Company’s Secretary.

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Standing Board Committee Governance Practices

The standing Board committees focus on good governance practices. These include:

Human Resources Committee Governance Practices

The Human Resources Committee obtains professional advice from an independent compensation consultant engaged directly by and who reports to the Committee. It is the Human Resources Committee’s view that its compensation consultant should be able to render candid and expert advice independent of management’s influence. In February 2018, the Human Resources Committee approved the continued engagement of Meridian as its independent compensation consulting firm. In its decision to retain Meridian as its independent compensation consultant, the Committee gave consideration to a broad range of attributes necessary to assist the needs of the Committee in setting compensation, including:

Meridian representatives attended all of the Human Resources Committee meetings during 2017. At the Human Resources Committee’s request, the consultant met regularly with the Committee members outside the presence of management, and spoke separately with the Committee Chair and other Committee members.

During 2017, the Committee requested of Meridian the following items:

Other than services provided to the Human Resources Committee as set forth above and for the Nominating and Corporate Governance Committee as described below, Meridian did not perform any other services for the Company or any of its subsidiaries in 2017.

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Pursuant to its letter agreement with the Committee, if the Company or management of the Company proposes that Meridian perform services for the Company or management of the Company other than in Meridian’s retained role as consultant to the Committee and the Nominating and Corporate Governance Committee, any such proposal is required to be submitted to the Committee for approval before such services begin.

In December 2017, the Nominating and Corporate Governance Committee also approved the continued engagement of Meridian as its independent consulting firm with respect to director compensation matters. See “— Director Compensation — Role of Director Compensation Consultant” below for a description of the services Meridian provided to the Nominating and Corporate Governance Committee in 2017.

Each of the Human Resources Committee and Nominating and Corporate Governance Committee has procedures for the purpose of determining whether the work of any compensation consultant raises any conflict of interest. Pursuant to such procedures, in December 2017 each such committee considered various factors, including the six factors mandated by SEC rules, and determined that with respect to executive and director compensation-related matters, no conflict of interest was raised by the work of Meridian.

Delegation of Authority

The Human Resources Committee has delegated authority to the Company’s Administrative Committee, comprised of designated members of management, to approve changes, within specified parameters, to certain of the Company’s retirement plans. It has also delegated authority to management to make pro rata equity grants in the first year of PSUP eligibility to executives who, while not Section 16 Officers, are newly promoted into a PSUP eligible role or hired into a PSUP eligible role from an external source during the year. In addition, the Human Resources Committee has delegated to the Chief Executive Officer the authority to make discretionary grants of equity awards from a pre-authorized pool of shares of Common Stock to executives who are not Section 16 Officers. The Company will ensure the total value of the equity grants made by the Chief Executive Officer does not exceed a specified limit.

Role of Executive Officers

The role of executive officers in compensation decisions for 2017 is described below under “EXECUTIVE COMPENSATION — COMPENSATION DISCUSSION AND ANALYSIS — Role of Executive Officers.” Mr. Baxter, as Chief Executive Officer of the Company, was not involved in determining his own compensation. See “EXECUTIVE COMPENSATION — COMPENSATION DISCUSSION AND ANALYSIS” below.

Human Resources Committee Interlocks and Insider Participation

No current member of the Human Resources Committee of the Board of Directors (Messrs. Johnson, Harshman, Lipstein and Wilson) was at any time during 2017 or at any other time an officer or employee of the Company, and no member had any relationship with the Company requiring disclosure under applicable SEC rules.

No executive officer of the Company has served on the board of directors or compensation committee of any other entity that has or has had one or more executive officers who served as a member of the Company’s Board of Directors or the Human Resources Committee during 2017.

Consideration of Director Nominees

The Nominating and Corporate Governance Committee will consider director nominations from shareholders in accordance with the Company’s Director Nomination Policy, a copy of which can be found on the Company’s website. The Nominating and Corporate Governance Committee will consider as a candidate any director of the Company who has indicated to the Nominating and Corporate Governance Committee that he or she is willing to stand for reelection as well as any other person who is recommended by any shareholders of the Company who provide the required information and certifications within the time requirements, as set forth in the Director Nomination Policy. The Nominating and Corporate Governance Committee may also undertake its own search process for candidates and may retain the services of

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professional search firms or other third parties to assist in identifying and evaluating potential nominees. In 2017, a third-party search firm was engaged by the Nominating and Corporate Governance Committee to assist in identifying and evaluating potential director nominees.

In considering a potential nominee for the Board, shareholders should note that in selecting candidates, the Nominating and Corporate Governance Committee endeavors to find individuals of high integrity who have a solid record of leadership and accomplishment in their chosen fields and who display the independence to effectively represent the best interests of all shareholders. Candidates are selected for their ability to exercise good judgment, to provide practical insights and diverse perspectives and to contribute to the regular refreshment of skill sets represented on the Board. Candidates also will be assessed in the context of the then-current composition of the Board, the average tenure of the Board, the operating requirements of the Company and the long-term interests of all shareholders. In conducting this assessment, the Nominating and Corporate Governance Committee will, in connection with its assessment and recommendation of candidates for director, consider diversity (including, but not limited to, gender, race, ethnicity, age, experience and skills), director tenure, board refreshment and such other factors as it deems appropriate given the then-current and anticipated future needs of the Board and the Company, and to maintain a balance of perspectives, qualifications, qualities and skills on the Board. Although the Nominating and Corporate Governance Committee may seek candidates that have different qualities and experiences at different times in order to maximize the aggregate experience, qualities and strengths of the Board members, nominees for each election or appointment of directors will be evaluated using a substantially similar process and under no circumstances will the Nominating and Corporate Governance Committee evaluate nominees recommended by a shareholder of the Company pursuant to a process substantially different than that used for other nominees for the same election or appointment of directors.

The Nominating and Corporate Governance Committee considers the following qualifications at a minimum in recommending to the Board potential new Board members, or the continued service of existing members:

Other than the foregoing, there are no stated minimum criteria for director nominees, although the Nominating and Corporate Governance Committee may also consider such other factors as it may deem are in the best interests of the Company and its shareholders. The Nominating and Corporate Governance Committee does, however, believe it appropriate for at least one member of the Board to meet the criteria for an “audit committee financial expert” as defined by SEC rules. In addition, because the Company is committed to maintaining its tradition of inclusion and diversity within the Board, each assessment and selection of director candidates will be made by the Nominating and Corporate Governance Committee in compliance with the Company’s policy of non-discrimination based on race, color, religion, sex, national origin, ethnicity, age, disability, veteran status, pregnancy, marital status, sexual orientation or any other reason prohibited by law. The Nominating and Corporate Governance Committee considers and assesses the implementation and effectiveness of its diversity policy in connection with Board nominations annually to assure that the Board contains an effective mix of individuals to best advance the Company’s long-term business interests.

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Pursuant to the Company’s Corporate Governance Guidelines, directors are expected to advise the Chairman of the Board and the Chair of the Nominating and Corporate Governance Committee prior to accepting any other company directorship or any assignment to the audit committee or compensation committee of the board of directors of any other company of which such director is a member. Directors accepting a directorship (or equivalent position) with a not-for-profit organization are also expected to advise the Chairman of the Board and the Chair of the Nominating and Corporate Governance Committee before or promptly after accepting such a position. The Company’s Corporate Governance Guidelines also provide that if a director has a significant change with respect to principal employment, he or she is required to notify the Nominating and Corporate Governance Committee and offer his or her resignation from the Board. The Nominating and Corporate Governance Committee will evaluate the facts and circumstances and make a recommendation to the Board whether to accept the resignation or request the director to continue to serve on the Board.

The Company’s Director Nomination Policy requires all directors standing for reelection to agree that in the event that any director fails to obtain the required majority vote at an annual meeting of shareholders, such director will tender his or her resignation as a director. The Nominating and Corporate Governance Committee will evaluate the best interests of the Company and its shareholders and will recommend to the Board the action to be taken with respect to such tendered resignation.

Board Succession Planning

The Board discusses formal succession planning on an annual basis, and the Nominating and Corporate Governance Committee, in accordance with its charter, the Company’s strategy and the Company’s Director Nomination Policy, regularly discusses in executive session board composition and refreshment.

Executive Sessions of Independent Directors

The independent directors meet privately in executive sessions to consider such matters as they deem appropriate, without management being present, as a routinely scheduled agenda item for every Board meeting. During 2017, all directors other than Mr. Baxter were independent (see “— Director Independence” below). Walter J. Galvin, who currently serves as the Lead Director, presides at the executive sessions. The Lead Director’s duties also include those detailed under “— Board Leadership Structure” above.

Executive Succession Planning

The Board establishes and reviews policies and procedures, consulting with the Nominating and Corporate Governance Committee, the Chairman and Chief Executive Officer and others, as it considers appropriate, regarding succession to the Chief Executive Officer position in the event of emergency or retirement. In furtherance thereof, the Board meets periodically in executive session to plan for succession with respect to the position of Chief Executive Officer and monitors management’s succession planning for other key executives.

Director Independence

Pursuant to NYSE listing standards, the Company’s Board of Directors has adopted a formal set of categorical independence standards with respect to the determination of director independence. These standards are set forth in the Company’s Director Nomination Policy. The provisions of the Director Nomination Policy regarding director independence meet and in some areas exceed the NYSE listing standards. In accordance with the Director Nomination Policy, in order to be considered independent a director must be determined to have no material relationship with the Company other than as a director.

The Director Nomination Policy specifies the criteria by which the independence of our directors will be determined.

Under the Director Nomination Policy, an “independent director” is one who:

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For purposes of determining a “material relationship,” the following standards are utilized:

For purposes of these independence standards, (i) immediate family members of a director include the director’s spouse, parents, stepparents, children, stepchildren, siblings, mother- and father-in-law, sons- and daughters-in-law, and brothers- and sisters-in-law and anyone (other than domestic employees) who shares the director’s home and (ii) the term “primary business affiliation” means an entity of which the director or the director’s immediate family member is a principal/executive officer or in which the director or the director’s immediate family member holds at least a five percent equity interest.

In accordance with the Director Nomination Policy, the Board undertook its annual review of director and director nominee independence. During this review, the Board considered transactions and relationships between each director and director nominee or any member of his or her immediate family and the Company

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and its subsidiaries and affiliates. The Board also considered whether there were any transactions or relationships between directors, nominees or any member of their immediate family (or any entity of which a director, director nominee or an immediate family member is an executive officer, general partner or significant equity holder). As provided in the Director Nomination Policy, the purpose of this review was to determine whether any such relationships or transactions existed that were inconsistent with a determination that the director or nominee is independent.

In evaluating the independence of directors, the Board considered all transactions between the Company and entities with which the directors and nominees are associated. Directors Fitzsimmons, Galvin, Johnson and Lipstein are affiliated with companies that purchased services from and/or sold services to the Company or its subsidiaries, which services were either rate-regulated or competitively bid. Directors Fitzsimmons, Galvin and Lipstein are affiliated with companies that purchased services from and/or sold services to the Company or its subsidiaries, which services were not rate-regulated or competitively bid but which were entered into in the ordinary course of business and on substantially the same terms as those prevailing at the time for comparable transactions with non-affiliated persons. In each case, the Board determined that the transactions were significantly below the thresholds under the director independence standards, under the NYSE requirements, and under the Company’s own standard for determining “material relationships” and did not affect the directors’ independence.

The Board also reviewed all contributions made by the Company and its subsidiaries to charitable organizations with which the directors or their immediate family members serve as an executive officer. The Board determined that the contributions were consistent with similar contributions, were approved in accordance with the Company’s normal procedures and were under the thresholds of the director independence requirements.

All of the referenced transactions discussed above were ordinary course commercial transactions made on an arm’s-length basis and on terms comparable to those generally available to unaffiliated third parties under the same or similar circumstances. The Board considered each of these transactions and relationships and determined that none of them was material or affected the independence of directors involved under either the general independence standards contained in the NYSE’s listing standards or the categorical standards contained in our Director Nomination Policy.

As a result of this review, the Board, at its meeting in February 2018, affirmatively determined that the following directors are independent under the standards set forth in the Director Nomination Policy: Catherine S. Brune, J. Edward Coleman, Ellen M. Fitzsimmons, Rafael Flores, Walter J. Galvin, Richard J. Harshman, Gayle P. W. Jackson, James C. Johnson, Steven H. Lipstein and Stephen R. Wilson; and that Warner L. Baxter, as President and Chief Executive Officer of the Company, is not independent under the Director Nomination Policy. In connection with his appointment to the Board in March 2018, the Board determined that Craig S. Ivey is also independent under the standards set forth in the Director Nomination Policy.

All members of the Audit and Risk Committee, the Human Resources Committee, the Nominating and Corporate Governance Committee, the Nuclear and Operations Committee and the Finance Committee of the Board of Directors are independent under the standards set forth in the Director Nomination Policy.

Related Person Transactions Policy

The Board of Directors has adopted the Ameren Corporation Related Person Transactions Policy. This written policy provides that the Nominating and Corporate Governance Committee will review and approve Related Person Transactions (as defined below); provided that the Human Resources Committee will review and approve the compensation of each Company employee who is an immediate family member of a Company director or executive officer and whose annual compensation exceeds $120,000. The Chair of the Nominating and Corporate Governance Committee has been delegated authority to act between Nominating and Corporate Governance Committee meetings.

The policy defines a “Related Person Transaction” as a transaction (including any financial transaction, arrangement or relationship (or any series of similar transactions, arrangements or relationships)) in which the Company (including any of its subsidiaries) was, is or will be a participant and the amount involved exceeds $120,000 and in which any Related Person (as defined below) had, has or will have a direct or indirect material

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interest, other than: (1) competitively bid or regulated public utility services transactions; (2) transactions involving trustee type services; (3) transactions in which the Related Person’s interest arises solely from ownership of Company equity securities and all equity security holders received the same benefit on a pro rata basis; (4) an employment relationship or transaction involving an executive officer and any related compensation solely resulting from that employment relationship or transaction if (i) the compensation arising from the relationship or transaction is or will be reported pursuant to the SEC’s executive and director compensation proxy statement disclosure rules or (ii) the executive officer is not an immediate family member of another executive officer or director and such compensation would have been reported under the SEC’s executive and director compensation proxy statement disclosure rules as compensation earned for services to the Company if the executive officer was a named executive officer as that term is defined in the SEC’s executive and director compensation proxy statement disclosure rules, and such compensation has been or will be approved, or recommended to our Board of Directors for approval, by the Human Resources Committee of our Board of Directors; or (5) compensation of or transaction with a director, if the compensation or transaction is or will be reported pursuant to the SEC’s executive and director compensation proxy statement disclosure rules.

“Related Person” is defined as (1) each director, director nominee and executive officer of the Company, (2) any person who is known by the Company (or any subsidiary of the Company) to be the beneficial owner of more than five percent of any class of the Company’s voting securities, (3) immediate family members of the foregoing persons and (4) any entity in which any of the foregoing persons is a general partner or principal or in a similar position or in which such person and all immediate family members of such person has a ten percent or greater beneficial interest.

The Office of the Corporate Secretary of the Company assesses whether a proposed transaction is a Related Person Transaction for purposes of the policy.

The policy recognizes that Related Person Transactions may, in some circumstances, be in the best interests of the Company and its shareholders.

The approval procedures in the policy identify the factors the Nominating and Corporate Governance Committee will consider in evaluating whether to approve or ratify Related Person Transactions or material amendments to pre-approved Related Person Transactions. The Nominating and Corporate Governance Committee will consider all of the relevant facts and circumstances available to the Nominating and Corporate Governance Committee, including (if applicable) but not limited to: the benefits to the Company; the actual or apparent conflict of interest of the Related Person in the event of the Related Person Transaction, including, but not limited to, the impact on a director’s independence; the availability and costs of other sources for comparable products or services; the terms of the transaction; the terms available to or from unrelated third parties or to employees generally; and an analysis of the significance of the transaction to both the Company and the Related Person. The Nominating and Corporate Governance Committee will approve or ratify only those Related Person Transactions (a) that are in compliance with applicable SEC rules and regulations, NYSE listing requirements and the Company’s policies, including but not limited to the Principles of Business Conduct and (b) that are in, or are not inconsistent with, the best interests of the Company and its shareholders, as the Nominating and Corporate Governance Committee determines in good faith. The policy provides for the pre-approval by the Nominating and Corporate Governance Committee of certain Related Person Transactions up to one year prior to the commencement of the transaction. The Human Resources Committee will review and approve on an annual basis the compensation of each Company employee who is an immediate family member of a Company director or executive officer and whose total annual compensation exceeds $120,000.

Based on the standards described above and certain determinations made by the Board discussed under “— Director Independence,” we had no Related Person Transactions in 2017.

Policy Regarding Communications to the Board of Directors

The Board of Directors has adopted a policy for shareholders and other interested persons to send communications to the Board. Shareholders and other interested persons who desire to communicate with the Company’s directors or a particular director may write to: Ameren Corporation Board of Directors, c/o Head of

Ameren Corporation  2018 Proxy Statement    35

Investor Relations, Mail Code 202, 1901 Chouteau Avenue, St. Louis, Missouri 63103. E-mail communications to directors should be sent to directorcommunication@ameren.com. All communications must be accompanied by the following information: if the person submitting the communication is a shareholder, a statement of the number of shares of the Company’s Common Stock that the person holds; if the person submitting the communication is not a shareholder and is submitting the communication to the Lead Director or the non-management directors as an interested party, the nature of the person’s interest in the Company; any special interest, meaning an interest not in the capacity of a shareholder of the Company, of the person in the subject matter of the communication; and the address, telephone number and e-mail address, if any, of the person submitting the communication. Communications received from shareholders and other interested persons to the Board of Directors will be reviewed by the Head of Investor Relations, or such other person designated by all non-management members of the Board, and if such communications are not solicitations, advertisements or other forms of mass mailings, they will be forwarded by the Office of the Corporate Secretary to the Lead Director or applicable Board member or members as expeditiously as reasonably practicable.

Annual Assessment of Board, Board Committee and Individual Director Performance

The Board of Directors annually reviews its performance, structure and processes in order to assess how effectively it is functioning. This assessment is implemented and administered by the Nominating and Corporate Governance Committee through an annual Board evaluation. Further, each of the Audit and Risk Committee, Human Resources Committee, Nominating and Corporate Governance Committee, Nuclear and Operations Committee and Finance Committee of the Board conducts an annual evaluation of its performance. After reviewing the Board evaluations, the Lead Director discusses the Board’s effectiveness with each director individually. The Lead Director reports on the Board evaluations. The full Board of Directors discusses the Board evaluation and committee evaluation reports to determine what, if any, action could improve (1) Board and Board committee performance and (2) if necessary, a director’s performance as it relates to the overall effectiveness of the Board.

In addition to the performance evaluations described above, the Nominating and Corporate Governance Committee also reviews annually the performance of all incumbent directors who are eligible for reelection at the Company’s next annual meeting of shareholders.

Shareholder Outreach and Engagement

The Company maintains an active shareholder engagement program to ensure regular communication with shareholders regarding areas of interest or concern. Each year, we conduct outreach to shareholders owning a significant percentage of our outstanding shares of Common Stock.

The Company’s outreach meetings have historically focused on its governance practices, executive compensation, and environmental matters and oversight. Shareholder feedback and suggestions that we receive are reported to the Nominating and Corporate Governance Committee, the Human Resources Committee, or the entire Board, as applicable, for consideration. Our recent engagement efforts have influenced our commitment to produce a climate risk report during the first quarter of 2019, the presentation of our director skills matrix in the proxy statement, and the terms of our proxy access by-law, among other things.

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DIRECTOR COMPENSATION

Role of Director Compensation Consultant

As noted above under “— CORPORATE GOVERNANCE — Human Resources Committee Governance Practices,” the Nominating and Corporate Governance Committee directly retains Meridian to advise it with respect to director compensation matters. During 2017, Meridian conducted an outside director market pay analysis for the Nominating and Corporate Governance Committee, as discussed further under “— Fees and Stock Awards” below, and attended a Nominating and Corporate Governance Committee meeting to discuss the analysis. Pursuant to policies and procedures established by the Board of Directors for the purpose of determining whether the work of any compensation consultant raised any conflict of interest, the Nominating and Corporate Governance Committee determined that with respect to director compensation-related matters, no conflict of interest was raised by the work of Meridian.

Fees and Stock Awards

The compensation program for non-management directors is reviewed on an annual basis by the Nominating and Corporate Governance Committee with a view to provide a pay program that compensates non-management directors at the median of the market. For 2017, this review, in consultation with its director compensation independent consultant, included an evaluation of a comparative peer group of companies that was identical to the 2016 PSUP peer group (as discussed under “— COMPENSATION DISCUSSION AND ANALYSIS — Long-Term Incentives: Performance Share Unit Program (“PSUP”)” in the proxy statement prepared in connection with the Company’s 2017 annual meeting of shareholders) to determine the overall competitiveness of pay and prevalence of program features of Ameren’s director compensation program.

The Board of Directors of Ameren has approved the following compensation program for each director who is not an employee of the Company: