UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

the Securities Exchange Act of 1934

Filed by the Registrantx

   ☒                             Filed by a Party other than the Registrant¨   ☐

Check the appropriate box:

WESTLAKE CHEMICAL CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

WESTLAKE CHEMICAL CORPORATION

2801 Post Oak Blvd.

Houston, Texas 77056

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held on May 10, 201613, 2021

To the Stockholders:

The annual meeting of stockholders of Westlake Chemical Corporation (the “Company” or “Westlake”) will be held at the Westlake Center, Annex, 2801 Post Oak Blvd., Houston, Texas 77056, on Tuesday,Thursday, May 10, 201613, 2021 at 9:00 a.m. local time for the following purposes:

The Board of Directors has fixed the close of business on March 14, 201615, 2021 as the record date for the determination of stockholders entitled to notice of, and to vote at, the annual meeting.

This year, weWe are using the Securities and Exchange Commission’s Notice and Access proxy rule, instead of mailing a printed set of materials to each stockholder. On March 31, 2016,April 2, 2021, we mailed to stockholders of record a Notice Regarding the Availability of Proxy Materials, with instructions on how to access the Company’s proxy materials via the Internet (or to request a printed copy) and how to vote online, by telephone or in person at the annual meeting.

All stockholders are requested to be present in person or by proxy. Please vote your proxy whether or not you plan to attend the annual meeting. You can vote your proxy either by the Internet, telephone or by requesting a printed copy of the materials and returning the proxy card enclosed with the printed materials in the envelope furnished for that purpose. Any stockholder may revoke a proxy for any reason and at any time before it is voted at the annual meeting.

Voting by the Internet or telephone is fast, convenient and your vote is immediately confirmed and tabulated. By using the Internet or telephone you help the Company reduce postage and proxy tabulation costs.

Your cooperation is appreciated as a majority of the common stock must be represented, either in person or by proxy, to constitute a quorum for the conduct of business.

By Order of the Board of Directors

L. Benjamin Ederington

Senior Vice President, General Counsel,

Chief Administrative Officer and Secretary

Dated: March 31, 2016April 2, 2021

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be Held on May 10, 2016:13, 2021:

This Proxy Statement, our annual report to stockholders and other proxy materials are available on the Internet atwww.proxyvote.com and atwww.westlake.com/proxy2016https://investors.westlake.com/financials/annual-and-proxy-reports/default.aspx.

WESTLAKE CHEMICAL CORPORATION

2801 Post Oak Blvd.

Houston, Texas 77056

PROXY STATEMENT

For the Annual Meeting of Stockholders to be Held on May 10, 201613, 2021

GENERAL MATTERS

This Proxy Statement and the accompanying form of proxy are being furnished to the stockholders of Westlake Chemical Corporation (the “Company” or “Westlake”) on or about March 31, 2016April 2, 2021 in connection with the solicitation of proxies by our Board of Directors for use at the annual meeting of stockholders to be held on Tuesday,Thursday, May 10, 201613, 2021 at 9:00 a.m. local time at the Westlake Center, Annex, 2801 Post Oak Blvd., Houston, Texas 77056, and any adjournment of the annual meeting.

The following matters will be acted upon at the annual meeting:

Our Board of Directors does not know of any other business to be brought before the annual meeting, but if any other business is properly brought before the annual meeting, proxies will be voted upon those matters in accordance with the judgment of the person or persons acting under the proxies.

All shares represented by validly authorized proxies will be voted in accordance with the instructions contained in the proxies. The Board of Directors recommends a vote:

In the absence of voting instructions to the contrary, shares represented by validly executed proxies will be voted in accordance with the foregoing recommendations. A stockholder giving a proxy has the power to revoke it at any time before it is voted at the annual meeting by providing written notice to the Secretary of the Company, by delivering a later-dated proxy, or by voting in person at the annual meeting.

Only stockholders of record at the close of business on March 14, 2016,15, 2021, also referred to as the record date, will be entitled to vote at the annual meeting. At the close of business on the record date, there were 130,290,754128,128,814 shares of common stock, par value $0.01 per share, outstanding, which represent all of the voting securities of the Company. Each share of common stock is entitled to one vote. Stockholders do not have cumulative voting rights in the election of directors.

A majority of the common stock entitled to vote at the annual meeting, present either in person or by proxy, will constitute a quorum. Abstentions and “broker non-votes” will be counted as present for purposes of determining whether there is a quorum present at the meeting. Shares held by a broker or other nominee as to which they have not received voting instructions from the beneficial owners and lack the discretionary authority to vote on a particular matter are called “broker non-votes.” Under the rules of the New York Stock Exchange, certain matters, such as the election of directors and the proposal to amend the Amended and Restated Certificate of Incorporation are not considered “routine” matters and, therefore, your broker will not have the discretionary authority to vote your shares on that matter if you have not given your broker specific instructions as to how to vote. Please be sure to give specific instructions to your broker.

Directors are elected by a plurality of the votes cast at the annual meeting, either in person or by proxy. Abstentions and broker non-votes will not be included in the total of votes cast and will not affect the outcome of the vote.

The

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An affirmative vote of a majority of the outstanding shares of the Company’s common stock, either in person or by proxy, is required to amend the Certificate of Incorporation to provide that the federal district courts of the United States of America will, with certain exceptions, be the exclusive forum for certain legal actions. Abstentions and broker non-votes will have the same effect as a vote against this proposal.

An affirmative vote of a majority of the votes cast at the annual meeting, either in person or by proxy, is required to ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm. Abstentions on the proposal to ratify the appointment of PricewaterhouseCoopers LLP will not be included in the total of votes cast and will not affect the outcome of the vote.

If your shares are held through a bank, broker or other nominee (i.e., in “street name”) and you have requested printed versions of these materials, the Company has asked your bank or broker to forward copies of the materials to you and

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to request your authority for execution of the proxies. The Company will reimburse the banks and brokers for their reasonable out-of-pocket expenses in doing so. Officers and employees of the Company may, without being additionally compensated, solicit proxies by mail, telephone, facsimile or personal contact. All proxy-soliciting expenses will be paid by the Company in connection with the solicitation of votes for the annual meeting. The Company has engaged Broadridge Financial Solutions, Inc. to tabulate voting results.

INFORMATION REGARDING THE BOARD OF DIRECTORS

INDEPENDENCE OF DIRECTORS

As of March 14, 2016,15, 2021, TTWF LP, our principal stockholder, and TTWFGP LLC, TTWF LP’s general partner, owned 70.6%72.4% of the outstanding common stock of the Company. Under the corporate governance rules of the New York Stock Exchange, we are considered to be controlled by TTWF LP. As a controlled company, we are eligible for exemptions from provisions of the New York Stock Exchange’s rules requiring a majority of independent directors, nominating and governance and compensation committees composed entirely of independent directors and written nominating and governance and compensation committee charters addressing specified matters. We have elected to take advantage of certain of these exemptions. In the event that we cease to be a controlled company within the meaning of these rules, we will be required to comply with these provisions after the specified transition periods.

Our Board of Directors has determined, after considering all of the relevant facts and circumstances, that Ms. Kimberly S. Lubel and Messrs. Robert T. Blakely, Michael J. Graff, Max L. Lukens,Marius A. Haas, Mark A. McCollum, R. Bruce Northcutt and H. John Riley, Jr.Jeffrey W. Sheets are independent from our management, as “independence” is defined by the rules and regulations of the Securities and Exchange Commission (“SEC”) and the listing standards of the New York Stock Exchange. This means that none of these directors has any direct or indirect material relationship with us, either directly or as a partner, stockholder or officer of an organization that has a relationship with us and that none of the express disqualifications contained in the New York Stock Exchange rules applies to any of them. In making its independence determinations, the Board of Directors considered the fact that, while such relationship does not preclude independence under the New York Stock Exchange rules, Mr. Graff is an executive officer of a company with which Westlake conducts business in the ordinary course.

EXECUTIVE SESSIONS

The Company’s governance guidelines require that non-management directors meet at regularly scheduled executive sessions without management. At these meetings of non-management directors, the non-management directors have decided that the non-management director that presides over the meeting will rotate among the non-management directors.

Since onethree of the non-management directors is(Ms. Jenkins and Messrs. David Chao and John Chao (until he was appointed Vice President and Managing Director of Westlake Innovations, Inc. (one of our subsidiaries) effective as of March 1, 2021)) are not independent, the Company’s governance guidelines require that the independent directors meet at least once a year. At these meetings of independent directors, the independent directors have decided that the independent director that presides over the meeting will rotate among the independent directors.

Stockholders and other interested parties may communicate with the non-management directors or the independent directors in the manner described under “Communications with Directors” below.

COMMITTEES OF THE BOARD OF DIRECTORS

The Audit Committee

The Audit Committee of the Board of Directors is currently comprised of Robert T. BlakelyMark A. McCollum (chairman), Michael J. Graff, Max L. Lukens,Marius A. Haas, Kimberly S. Lubel, R. Bruce Northcutt and H. John Riley, Jr.Jeffrey W. Sheets. Mr. Max L. Lukens served as a

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member of the Audit Committee until May 2020. All current Audit Committee members are “independent” as defined by the listing standards of the New York Stock Exchange and Section 10A(m)(3) of the Securities Exchange Act of 1934. The board has determined that each of Messrs. Blakely, Graff, Lukens,Haas, McCollum, Northcutt and RileySheets and Ms. Lubel is an “audit committee financial expert” as that term is defined by SEC regulations. The primary functions of the Audit Committee are to review the adequacy of the system of internal controls and management information systems, to review the results of our independent registered public accounting firm’s quarterly reviews of our interim financial statements, to review the planning and results of the annual audit with our independent registered public accounting firm and to have oversight of financial risks. This Committee held seven meetings in 2015.2020. The Board of Directors has adopted a written charter for the Audit Committee. The Audit Committee charter is publicly available on our website at: http://www.westlake.com under “Investor Relations—Corporate Governance.”

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Mr. Blakely is currently serving on the audit committees of four public companies, including the Company’s Audit Committee. In May 2009, prior to his commencement of service on the fourth audit committee, and again most recently in February 2016, the Board of Directors of the Company determined that his service on these other audit committees does not impair his ability to effectively serve on the Company’s Audit Committee.

The Compensation Committee

The Compensation Committee of the Board of Directors is currently comprised of R. Bruce Northcutt (chairman), RobertAlbert Y. Chao, David T. Blakely, Albert Chao, James Y. Chao, John T. Chao, Michael J. Graff, Marius A. Haas, Dorothy C. Jenkins, Max L. LukensKimberly S. Lubel, Mark A. McCollum and H. John Riley, Jr.Jeffrey W. Sheets (i.e., all of the members of the Board of Directors). Mr. Max L. Lukens served as a member of the Compensation Committee until May 2020. Since Westlake is considered to be controlled by a principal stockholder under New York Stock Exchange rules, all Compensation Committee members are not required to be independent as defined by the listing standards of the New York Stock Exchange. Messrs. Albert Chao, David Chao, James Chao and John Chao and Ms. Jenkins are not “independent” as defined by those listing standards. The Compensation Committee’s primary functions include overseeing our executive compensation, director compensation and equity and performance incentive compensation plans and policies. This Committee held five meetings in 2015.2020. The Compensation Committee has adopted a written charter. The Compensation Committee charter is publicly available on our website at: http://www.westlake.com under “Investor Relations—Corporate Governance.”

The Nominating and Governance Committee

The Nominating and Governance Committee is currently comprised of H.Jeffrey W. Sheets (chairman), Albert Y. Chao, David T. Chao, James Y. Chao, John Riley, Jr. (chairman), Robert T. Blakely, Albert Chao, James Chao, Michael J. Graff, Marius A. Haas, Dorothy C. Jenkins, Max L. LukensKimberly S. Lubel, Mark A. McCollum and R. Bruce Northcutt (i.e., all of the members of the Board of Directors). Mr. Max L. Lukens served as a member of the Nominating and Governance Committee until May 2020. Since Westlake is considered to be controlled by a principal stockholder under New York Stock Exchange rules, all Nominating and Governance Committee members are not required to be independent as defined by the listing standards of the New York Stock Exchange. Messrs. Albert Chao, David Chao, James Chao and John Chao and Ms. Jenkins are not “independent” as defined by those listing standards. The Nominating and Governance Committee’s primary functions are (1) to identify individuals qualified to become directors of the Company, (2) to recommend to the Board of Directors director candidates to fill vacancies on the Board of Directors and to stand for election by the stockholders at the annual meeting of stockholders, (3) to recommend committee assignments for directors, (4) to monitor and annually assess the performance of the Board of Directors and its committees, and (5) to develop and recommend to the Board of Directors appropriate corporate governance policies, practices and procedures for the Company. In assessing the qualifications of prospective nominees to serve as directors, this Committee will consider, in addition to any criteria set forth in the Bylaws of the Company, each nominee’s personal and professional integrity, experience, skills, ability and willingness to devote the time and effort necessary to be an effective director, and commitment to acting in the best interests of the Company and its stockholders. This Committee held four meetings in 2015.2020. The Nominating and Governance Committee has the authority to retain an executive search firm as needed to identify director candidates. The Nominating and Governance Committee has adopted a written charter. The charter is publicly available on our website at: http://www.westlake.com under “Investor Relations—Corporate Governance.”

The Nominating and Governance Committee will consider nominees recommended by stockholders. Any recommendation should be addressed in writing to the Nominating and Governance Committee, Westlake Chemical Corporation, c/o Corporate Secretary, 2801 Post Oak Blvd., Houston, Texas 77056. Recommendations for potential nominees may come from any source, including members of the Board of Directors, stockholders, self-recommendations or search firms. All persons recommended for a vacant or new Board position will be given equal consideration regardless of the source of the recommendation. The Nominating and Governance Committee takes diversity, broadly defined to include gender, ethnicity, national origin, geographic location, expertise and level and type of career experience, into account in evaluating the qualifications of prospective nominees to the Board.

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BOARD LEADERSHIP STRUCTURE

We have separated the positions of chairman of the board and chief executive officer. Mr. James Chao serves as our Chairman of the Board and Mr. Albert Chao serves as our Chief Executive Officer. Our Board has concluded that balance and varying experience and judgment are added to the leadership of the Board by having these two positions filled by different persons.

Mr. James Chao, our Chairman of the Board, is not independent from our management, as “independence” is defined by the rules and regulations of the SEC and the listing standards of the New York Stock Exchange. Our independent directors meet at least once a year. At these meetings, the independent director that presides over the meeting rotates among the independent directors. See “Information Regarding Board of Directors—Executive Sessions.” We believe that this leadership structure is appropriate because we are controlled by TTWF LP, our principal stockholder.

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BOARD ROLE IN CORPORATE RISK OVERSIGHT

TheIn February 2021, the Board of Directors has formed aamended the charter of the Corporate Risk Committee and changed the name of the Committee to the Corporate Risk and Sustainability Committee. The Corporate Risk and Sustainability Committee of our Board of Directors which is currently comprised of Michael J. Graff (chairman), RobertAlbert Y. Chao, David T. Blakely, Albert Chao, James Y. Chao, John T. Chao, Marius A. Haas, Dorothy C. Jenkins, Max L. Lukens,Kimberly S. Lubel, Mark A. McCollum, R. Bruce Northcutt and H. John Riley, Jr.Jeffrey W. Sheets (i.e., all of the members of the Board of Directors). Mr. Max L. Lukens served as a member of the Corporate Risk Committee until May 2020. This Committee assists the Board in overseeing overall risks inherent in the operations of the Company and the control processes with respect to those risks.risks (including, but not limited to, environmental, health, safety, sustainability and cybersecurity risks). Among other things, this Committee reviews the risk-management structure of the Company and reviews management’s identification and assessment of significant risks and its plans to control those risks. The Corporate Risk and Sustainability Committee also reviews management’s systems as they relate to enterprise-wide risks posed by the Company’s physical assets and operating processes and addresses the findings of regulatory agencies concerning the Company’s physical assets and operations. This Committee held four meetings in 2015.2020.

As previously described, our Board’s Audit Committee retains responsibility for oversight of financial risks, including integrity of financial statements, internal controls, derivatives transactions, loan covenant compliance, credit, liquidity, insurance and similar areas. Further, our Board’s Compensation Committee retains responsibility for oversight of compensation and personnel practices, including succession planning and management development. Finally, our Board of Directors retains ultimate responsibility for corporate risk oversight as a whole as well as responsibility for oversight of specific risks not assigned to the Board’s committees. As requested from time to time by the Board and its committees, members of our senior management present reports to the Board and the committees on the risks that we face.

COMPENSATION-RELATED RISK

The Company regularly assesses risks related to its compensation program, including its executive compensation program, and does not believe that the risks arising from the Company’s compensation policies and practices are reasonably likely to have a material adverse effect on the Company. Management reports to the Compensation Committee and the Corporate Risk and Sustainability Committee regarding factors that could mitigate or encourage excessive risk-taking in reference to the compensation practices of the Company. In addition, the Compensation Committee has independently engaged Willis Towers Watson as its compensation consultant to provide regular reports to the Committee regarding best practices, risk factors, program design and related matters. The Compensation Committee also considered the attributes of the Company’s programs, including:

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CORPORATE GOVERNANCE

We have a Code of Ethics that applies to our principal executive officer, principal financial officer and principal accounting officer, a Code of Conduct that applies to all directors, officers and employees, and Principles of Corporate Governance. You can find the above-referenced documents by visiting our website at: http://www.westlake.com under “Investor Relations—Corporate Governance.” We will post on our website any amendments to such documents as well as any waivers that are required to be disclosed by the rules of either the SEC or the New York Stock Exchange.

COMMUNICATIONS WITH DIRECTORS

Any interested party is welcome to communicate with any one or all of our directors by writing to the director or directors, Westlake Chemical Corporation, c/o Corporate Secretary, 2801 Post Oak Blvd., Houston, Texas 77056. The Corporate Secretary will forward these communications to the addressee. If any interested party would like to communicate with the non-management directors or independent directors as a group, the interested party should address such

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communication as follows: Non-management Directors or Independent Directors (as applicable), Westlake Chemical Corporation, c/o Corporate Secretary, Westlake Chemical Corporation, 2801 Post Oak Blvd., Houston, Texas 77056. Upon receipt, Westlake’s Corporate Secretary will forward the communication, unopened, to one of the non-management directors or independent directors, as applicable. Such director will, upon review of the communication, make a determination as to whether it should be brought to the attention of the other non-management directors or independent directors, as applicable, and whether any response should be made to the person sending the communication, unless the communication was made anonymously.

MEETING ATTENDANCE

The Board of Directors held sevensix meetings in 2015.2020. During 2015,2020, all of our directors except Michael J. Graff, attended at least 75% of the total number of meetings of the Board of Directors and any committee on which he or she served during the periods that he or she served. Mr. Graff was unable to attend certain board committee meetings toward the end of 2015 in connection with the announcement of the $13.4 billion acquisition by his company, Air Liquide, S.A, of Airgas, Inc. Westlake encourages its directors to attend the annual meeting of stockholders. All eight of our directors attended our annual meeting of stockholders in 2015.2020.

COMPENSATION OF DIRECTORS

Directors who are also full-time officers or employees of Westlake receive no additional compensation for serving as directors. In 2015,2020, all other directors who served for the whole year received an annual cash retainer of $100,000. The Audit Committee chairman received an additional annual retainer of $17,500,$22,500 (the annual retainer was increased from $20,000 to $25,000 effective for the third quarter of 2020), the Compensation Committee chairman received an additional annual retainer of $15,000,$18,750 (the annual retainer was increased from $17,500 to $20,000 effective for the third quarter of 2020), the Nominating and Governance Committee chairman received an additional annual retainer of $10,000$15,000 and the Corporate Risk and Sustainability Committee chairman received an additional annual retainer of $10,000.$15,000. Under the 2013 Omnibus Incentive Plan, as amended and restated on May 19, 2017 (the “2013 Plan”), the Board of Directors, effective August 20, 2015,May 15, 2020, authorized the issuance of 1,8093,780 restricted stock units to each non-management director. TheseMs. Kimberly S. Lubel in connection with her appointment to the Board of Directors. All of these restricted stock units will vest in three equal installments on August 21, 2016, 2017 and 2018,May 15, 2021, subject to the grantee’s continuous positionher continuing service as a director of Westlake as of the applicablevesting date. The Board of Directors, effective August 14, 2020, authorized the issuance of 2,400 restricted stock units to each non-management director at the time (being Mss. Jenkins and Lubel and Messrs. David Chao, John Chao, Graff, Haas, McCollum, Northcutt and Sheets). All of these restricted stock units will vest on August 14, 2021, subject to the grantee’s continuing service as a director of Westlake as of the vesting date. Each such restricted stock unit represents a contingent right to receive one share of Westlake’s common stock at vesting.

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The following table sets forth a summary of the compensation earned or paid to our non-management directors in 2015:2020:

PROPOSAL 1—ELECTION OF CLASS IIIII DIRECTORS

Our Amended and Restated Certificate of Incorporation provides that the Board of Directors be divided into three classes, each consisting, as nearly as possible, of one-third of the total number of directors constituting the Board of Directors, with each class to serve for a term of three years. The following nominees, each of whom is an incumbent Class III director and was nominated by our Nominating and Governance Committee, are proposed for election in Class III,II, to serve until the annual meeting of stockholders in 2019,2024, or until their successors are elected and qualified:

Messrs. James Chao, John Chao, McCollum and Northcutt are incumbent Class II directors. Unless instructed otherwise, the proxies will be voted for the election of the threefour nominees named above. If any nominee is unable to serve, proxies may be voted for a substitute nominee selected by the Board of Directors, although management is not aware of any circumstance likely to render any of the named nominees unavailable for election.

THE BOARD OF DIRECTORS RECOMMENDS A VOTE FOR

THE ELECTION OF THESE NOMINEES AS CLASS IIIII DIRECTORS.

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NOMINEES FOR ELECTION AS CLASS IIIII DIRECTORS

Robert T. Blakely (age 74). Mr. Blakely has been a director since August 2004. Mr. Blakely served as Chief Financial Officer of the Federal National Mortgage Association (Fannie Mae) from January 2006 until August 2007. He served as Fannie Mae’s Executive Vice President from January 2006 until January 2008. His prior positions include: Executive Vice President and Chief Financial Officer of MCI, Inc. from April 2003 to January 2006; President of Performance Enhancement Group, Ltd. from July 2002 to April 2003; Executive Vice President and Chief Financial Officer of Lyondell Chemical Company from November 1999 to June 2002; Executive Vice President of Tenneco Inc. from 1996 to November 1999 and Chief Financial Officer from 1981 to November 1999; and Managing Director of Morgan Stanley & Co. from 1980 to 1981 and an employee from 1970. He has served on the Board of Directors of Natural Resource Partners L.P. from January 2003 to the present, the Board of Directors of Greenhill & Co., Inc. from April 2009 to the present and the Board of Directors of Ally Financial (formerly GMAC Inc.) from May 2009 to the present. He is a trustee emeritus of Cornell University. From 2007 to late 2012, he served as a Trustee of the Financial Accounting Foundation. He is also a director of the Episcopal Hospital Health Foundation and the Baylor St. Luke’s Medical Center. He holds a B.M.E. degree in mechanical engineering and an M.B.A. in business administration from Cornell University and a Ph.D. from the Massachusetts Institute of Technology.

The Board has concluded that Mr. Blakely should serve as a director of the Company based primarily on his long experience as a corporate executive of public companies, his prior tenure as a senior officer of a company in the chemicals industry, his service as the chief financial officer of several public companies and his broad background in the field of financial accounting.

AlbertJames Y. Chao (age 66). Mr. Chao has been our President since May 1996 and a director since June 2003. Mr. Chao became our Chief Executive Officer in July 2004. Mr. Chao has over 40 years of global experience in the chemical industry. In 1985, Mr. Chao assisted his father, T.T. Chao, and his brother, James Chao, in founding Westlake, where he served as Executive Vice President until he succeeded James Chao as President. He has held positions in the Controller’s Group of Mobil Oil Corporation, in the Technical Department of Hercules Incorporated, in the Plastics Group of Gulf Oil Corporation and has served as Assistant to the Chairman of China General Plastics Group and Deputy Managing Director of a plastics fabrication business in Singapore. Mr. Chao is a trustee of Rice University. Mr. Chao received a bachelor’s degree from Brandeis University and an M.B.A. from Columbia University.

The Board has concluded that Mr. Albert Chao should serve as a director of the Company based primarily on his long experience in the global chemicals and plastics industries and his lengthy tenure as a senior officer of the Company. Mr. Chao also brings important perspectives to our Board from his position as a member of the Chao family, which controls TTWF LP, our principal stockholder.

Michael J. Graff (age 60). Mr. Graff has been a director since May 2013. Mr. Graff is Chairman and Chief Executive Officer of American Air Liquide Holdings, Inc. and a Senior Vice President of the Air Liquide Group with responsibility for the Americas, Safety and Industrial Systems Worldwide and is Chairman of the Electronics World Business Line. Mr. Graff joined Air Liquide as President and CEO of Air Liquide USA LLC in April 2007. In January 2009, he took on additional responsibilities and was named President and CEO of American Air Liquide Holdings, Inc. In May 2009, Mr. Graff

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was named a Corporate Vice President of Air Liquide S.A. and member of the Executive Committee of the Air Liquide Group with responsibilities for North America and Safety and Industrial Systems Worldwide. In January 2010, Mr. Graff’s responsibilities were expanded to include responsibility for all of Air Liquide’s operations in the Western hemisphere (Americas). In April 2012, Mr. Graff’s responsibilities were expanded to include oversight of Air Liquide’s electronic business worldwide and he was named Chairman of the Electronics World Business Line. In January 2013 Mr. Graff was named a Senior Vice Present of the Air Liquide Group and in April 2013 he was named Chairman of American Air Liquide Holdings, Inc. Prior to joining Air Liquide, Mr. Graff began his career with Amoco Corporation and then worked for BP plc, where he last served as President and Chief Executive Officer of BP Polymers Americas from 2001 to 2004. Mr. Graff served as a director of The Lubrizol Corporation from 2009 until it was acquired by Berkshire Hathaway Inc. in 2011. Mr. Graff serves on the Board and the Executive Committee of the American Chemistry Council, the Board of the National Association of Manufacturers and the Board of the U.S. Chamber of Commerce. He is also the Chairman of the Society for Chemical Industries and a principal of the American Energy Innovation Council. Mr. Graff serves on the Board and Executive Committee of Children at Risk. He is also a member of the Greater Houston Partnership and a member of the Energy Forum of the Baker Institute at Rice University and serves on the Board of Trustees of the Illinois Institute of Technology. Mr. Graff holds an M.S. in Chemical Engineering from Purdue University, a B.S. in Chemical Engineering from the Illinois Institute of Technology, has studied business at the University of Chicago and has completed executive management programs at the Wharton School of the University of Pennsylvania, the University of Cambridge and the Stanford University Law School.

The Board has concluded that Mr. Graff should serve as a director of the Company based primarily on his extensive experience in the energy, chemicals and polymers industries and his experience as a chief executive officer.

Class I Directors Serving Until 2017

Dorothy C. Jenkins (age 70). Ms. Jenkins has been a director since June 2003. For the past five years, Ms. Jenkins has managed her personal investments. She is also a member of the board of various civic and charitable organizations including Wellesley College. Ms. Jenkins is the sister of James Chao and Albert Chao. She is a graduate of Wellesley College and holds a B.A. in Mathematics.

The Board has concluded that Ms. Jenkins should serve as a director of the Company based primarily on her experience on the boards of charitable and community organizations and her position as a member of the Chao family, which controls TTWF LP, our principal stockholder.

Max L. Lukens (age 67). Mr. Lukens has been a director since August 2004. Since May 2006, Mr. Lukens has managed his personal investments. Mr. Lukens served as President and Chief Executive Officer of Stewart & Stevenson Services, Inc. until May 2006 and prior to that served as its Chairman of the Board from December 2002 to March 2004, and Interim Chief Executive Officer and President from September 2003 to March 2004. He was also previously employed by Baker Hughes Incorporated from 1981 to January 2000, where he served as Baker Hughes’ Chairman of the Board, President and Chief Executive Officer from 1997 to January 2000. Since July 2015, Mr. Lukens has served on the Board of Directors of Blount International, Inc. Between 2003 and 2009, he served as a director of NCI Building Systems, Inc. He also served as a director of The Pep Boys—Manny, Moe & Jack from August 2006 until October 2007 and again from June 2009 until September 2011. He was also Chairman of the Board of that company from June 2009 until he resigned in September 2011. Mr. Lukens was a Certified Public Accountant with Deloitte Haskins & Sells for 10 years and received both his B.S. and M.B.A. degrees from Miami University.

The Board has concluded that Mr. Lukens should serve as a director of the Company based primarily on his long experience as a chief executive officer of public companies, as well as his service on the boards of other public companies and his earlier career as a certified public accountant.

Class II Directors Serving Until 2018

James Chao (age 68)73). Mr. Chao has been our Chairman of the Board since July 2004 and became a director in June 2003. From May 1996 to July 2004, he served as our Vice Chairman. Mr. Chao also has responsibility for the oversight of our Vinyls business. Mr. Chao has over 45 years of global experience in the chemical industry. From June 2003 until November 2010, Mr. Chao was the executive chairman of Titan Chemicals Corp. Bhd. Prior to that he served as Titan’s Managing Director. He has served as a Special Assistant to the Chairman of China General Plastics Group and worked in various financial, managerial and technical positions at Mattel Incorporated, Developmental Bank of Singapore, Singapore Gulf Plastics Pte. Ltd. and Gulf Oil Corporation. Mr. Chao, along with his brother, Albert Chao, assisted their father, T.T. Chao, in founding Westlake. Mr.He is the brother of Albert Y. Chao is on the boardand Dorothy C. Jenkins, father of Baylor CollegeDavid T. Chao and uncle of Medicine and KIPP (Knowledge is Power Program).John T. Chao. Mr. Chao received his B.S. degree from the Massachusetts Institute of Technology and an M.B.A. from Columbia University.

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The Board has concluded that Mr. James Chao should serve as a director of the Company based primarily on his long experience in the global chemicals and plastics industries and his lengthy tenure as a senior officer of the Company. Mr. Chao also brings important perspectives to our board as a member of the Chao family, which controls TTWF LP, our principal stockholder.

John T. Chao (age 44). Mr. Chao has been a director since August 2018. Mr. Chao was appointed Vice President and Managing Director of Westlake Innovations, Inc. (one of our subsidiaries) effective as of March 1, 2021. From October 2018 to February 28, 2021, he was a Managing Director of Tanglewood Property Management Company, an affiliate of our principal stockholder. From March 2015 to October 2018, he was with New York Public Radio, as the organization’s Vice President of Partnerships and New Business from March 2015 to June 2016, Senior Vice President of Business and Strategy from June 2016 to August 2017 and Chief Operating Officer from August 2017 to October 2018. Mr. Chao was previously in the strategy and finance practice at McKinsey & Company where he advised energy and commodity companies, beginning in 2004 and ending his tenure as a partner in 2013. From 2000 to 2002, he was a financial analyst at the Company. He is the son of Albert Y. Chao, the nephew of James Y. Chao and Dorothy C. Jenkins and the cousin of David T. Chao. Mr. Chao received a bachelor’s degree in chemical engineering from Rice University and an M.B.A. from the Massachusetts Institute of Technology.

The Board has concluded that Mr. John Chao should serve as a director of the Company based primarily on his experience with the chemical, energy and other commodity industries and his position as a member of the Chao family, which controls TTWF LP, our principal stockholder.

Mark A. McCollum (age 62). Mr. McCollum has been a director since May 2018. Mr. McCollum was the President and Chief Executive Officer of Weatherford International plc from April 2017 to June 2020. Weatherford filed for voluntary Chapter 11 bankruptcy in July 2019 and emerged in December 2019. Prior to joining Weatherford, Mr. McCollum served as Executive Vice President and Chief Financial Officer of Halliburton Company, a position he assumed in 2008 and resumed in July 2016 following an interim role from December 2014 to July 2016 as Executive Vice President and Chief Integration Officer during the pendency of Halliburton’s proposed acquisition of Baker Hughes Incorporated. From 1995 to 2003, Mr. McCollum held a number of senior positions at Tenneco, Inc., including Chief Financial Officer, and, from 1991 to 1995, served as an Audit and Advisory Partner in Arthur Andersen’s Energy Division, where he began his career. He served on the Board of Directors of Archrock, Inc. from 2002 to July 2018. He currently serves on the Board of Trustees for Baylor College of Medicine and Yellowstone Academy. Mr. McCollum received a bachelor’s of Business Administration degree in Accounting from Baylor University in 1980 and is a CPA in Texas.

The Board has concluded that Mr. McCollum should serve as a director of the Company based primarily on his extensive experience in the oilfield services and energy industries and his broad background in the field of financial accounting.

R. Bruce Northcutt (age 56)61). Mr. Northcutt has been a director since May 2013. Mr. Northcutt has been a partner of Navitas Midstream Partners, LLC since November 2013 and the Chairman of the Board, Chief Executive Officer and President of its manager, Navitas Midstream Management, LLC, since May 2014. Mr. Northcutt was the President and Chief Executive Officer and a director of Copano Energy, L.L.C. until its acquisition by Kinder Morgan Energy Partners, L.P. in May 2013. Mr. Northcutt had also served as Copano’s President and Chief Operating Officer from April 2003 until November 2009. Mr. Northcutt served as President of El Paso Global Networks Company from November 2001 until April 2003; Managing Director of El Paso Global Networks Company from April 1999 until November 2001 and Vice President, Business Development, of El Paso Gas Services Company from January 1998 until April 1999. From 1988 until 1998, Mr. Northcutt held positions with various levels of responsibility at El Paso Energy and its predecessor, Tenneco Energy, including supervision of pipeline supply and marketing as well as regulatory functions. He began his career with Tenneco Oil Exploration and Production in 1982, working in the areas of drilling and production engineering. Mr. Northcutt holds a

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Bachelor of Science degree in Petroleum Engineering from Texas Tech University and is a Registered Professional Engineer on inactive status in the State of Texas.

The Board has concluded that Mr. Northcutt should serve as a director of the Company based primarily on his extensive experience in the energy industry and his experience as a chief executive officer.

Class I Directors

H. John Riley, Jr.Marius A. Haas (age 75)53). Mr. RileyHaas has been a director since November 2007.January 2018. He has been with BayPine Capital, where he is Partner and Co-Founder, since March 2020. Mr. RileyHaas served as ChairmanPresident and Chief Commercial Officer of the Board of Directors of Cooper Industries, Ltd., from May 1996 until February 2006 and served as its Chief Executive OfficerDell EMC from September 2016 to February 2020 and previously was Chief Commercial Officer and President of Enterprise Solutions for Dell Inc. from August 2012 to September 2016. Prior to joining Dell, Mr. Haas was with Kohlberg Kravis Roberts & Co. from June 2011 to August 2012 and with HP Inc. and its predecessor companies from August 1995 to May 2005. He was PresidentJune 2011, where he served in a variety of Cooper Industries, Ltd. from 1992 to 2004, its Chief Operating Officer from 1992 to 1995 and its Executiveroles, including as Senior Vice President Operationsand Global Manager of HP’s Networking Division and as Senior Vice President and Chief Strategy Officer. Mr. Haas received a bachelor’s degree from 1982 to 1992. He was associated with Cooper Industries, Ltd. for more than 40 years. In addition,Georgetown University and an M.B.A. from 1997 to May 2013 he served as a directorthe Thunderbird School of Baker Hughes Incorporated and, from 1998 to May 2014, he served as a director of Allstate Corporation. He currently serves as a director of Post Oak Bank, N.A., a private bank. He is a trustee of the Museum of Fine Arts in Houston and a trustee of SyracuseGlobal Management at Arizona State University. Mr. Riley holds a B.S. in Industrial Engineering from Syracuse University. He also completed the Harvard University Advanced Management Program.

The Board has concluded that Mr. RileyHaas should serve as a director of the Company based primarily on his experience as a senior executive of public companies and in the private equity field, as well as his perspective from businesses that are outside the chemical industry.

Dorothy C. Jenkins (age 75). Ms. Jenkins has been a director since June 2003. For the past five years, Ms. Jenkins has managed her personal investments. Ms. Jenkins is the sister of James Y. Chao and Albert Y. Chao and aunt of David T. Chao and John T. Chao. She is a graduate of Wellesley College and holds a B.A. in Mathematics.

The Board has concluded that Ms. Jenkins should serve as a director of the Company based primarily on her experience on the boards of charitable and community organizations and her position as a member of the Chao family, which controls TTWF LP, our principal stockholder.

Kimberly S. Lubel (age 56). Ms. Lubel has been a director since May 2020. Ms. Lubel served as the Chairman, President and Chief Executive Officer of CST Brands, Inc. from its spin-off from Valero Energy Corporation in 2013 until CST’s acquisition by Alimentation Couche-Tard Inc. in June 2017. From October 2008 through December 2012, Ms. Lubel served as Valero’s Executive Vice President and General Counsel, with responsibility over Valero’s legal, ad valorem tax, health, safety and environmental, energy and gases, reliability and project execution departments. She joined Valero in 1997. Ms. Lubel has served on the Board of Directors of PBF Energy Inc. since August 2017 and on the Board of Directors of the Southwest Research Institute since 2019. Previously, Ms. Lubel served on the Board of Directors of WPX Energy Inc. from December 2011 through January 2021. Ms. Lubel holds a bachelor’s of arts degree in Spanish and international studies from Miami University (Ohio), a master of arts degree in international relations from Baylor University and a juris doctorate degree from the University of Texas School of Law. She is also a graduate of the Executive Program at Stanford University.

The Board has concluded that Ms. Lubel should serve as a director of the Company based primarily on her long experience in the petroleum refining and fuel and convenience retailing industries and her extensive experience in legal and related areas.

Jeffrey W. Sheets (age 63). Mr. Sheets has been a director since January 2018. Mr. Sheets served as Executive Vice President and Chief Financial Officer of ConocoPhillips Company from October 2010 to February 2016. Mr. Sheets was associated with ConocoPhillips and its predecessor companies for more than 36 years and served in a variety of roles, including Senior Vice President of Planning and Strategy and Vice President and Treasurer. He began his career with Phillips Petroleum Company in 1980 as a process engineer. Mr. Sheets also serves on the Board of Directors of Enerplus Corporation and Schlumberger Limited, and is a former director of DCP Midstream Partners LP. Mr. Sheets received a bachelor’s degree in chemical engineering from the Missouri University of Science and Technology and an M.B.A. from the University of Houston. Mr. Sheets is a member of the Board of Trustees at the Missouri University of Science and Technology.

The Board has concluded that Mr. Sheets should serve as a director of the Company based primarily on his long experience in the petroleum industry and his extensive experience in financial accounting and related areas.

Class III Directors

Albert Y. Chao (age 71). Mr. Chao has been our President since May 1996 and a director since June 2003. Mr. Chao became our Chief Executive Officer in July 2004. Mr. Chao has over 40 years of global experience in the chemical industry.

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In 1985, Mr. Chao assisted his father, T.T. Chao, and his brother, James Chao, in founding Westlake, where he served as Executive Vice President until he succeeded James Chao as President. He has held positions in the Controller’s Group of Mobil Oil Corporation, in the Technical Department of Hercules Incorporated, in the Plastics Group of Gulf Oil Corporation and has served as Assistant to the Chairman of China General Plastics Group and Deputy Managing Director of a plastics fabrication business in Singapore. Mr. Chao is a trustee emeritus of Rice University. He is the brother of James Y. Chao and Dorothy C. Jenkins, father of John T. Chao and uncle of David T. Chao. Mr. Chao received a bachelor’s degree from Brandeis University and an M.B.A. from Columbia University.

The Board has concluded that Mr. Albert Chao should serve as a director of the Company based primarily on his long experience in the global chemicals and plastics industries and his lengthy tenure as a senior officer includingof the Company. Mr. Chao also brings important perspectives to our Board from his position as a member of the Chao family, which controls TTWF LP, our principal stockholder.

David T. Chao (age 44). Mr. Chao has been a director since January 2018. Mr. Chao is the Executive Chairman of Tanglewood Property Management Company, an affiliate of our principal stockholder, a position he has held since July 2017. From August 2013 to July 2017, Mr. Chao was the Company’s Vice President of Business Development for Asia and Middle East and from July 2011 to August 2013 he was the Company’s Director of Business Development for Asia and Middle East. Prior to joining Westlake, Mr. Chao was President and Director at PT Titan Petrokimia Nusantara, a petrochemical company based in Indonesia, from January 2008 to December 2010. He is the son of James Y. Chao, the nephew of Albert Y. Chao and Dorothy C. Jenkins and the cousin of John T. Chao. Mr. Chao received a bachelor’s degree in mechanical engineering from Rice University and an M.B.A. from the Wharton School of the University of Pennsylvania.

The Board has concluded that Mr. David Chao should serve as a director of the Company based primarily on his experience in the chemical industry and his position as a member of the Chao family, which controls TTWF LP, our principal stockholder.

Michael J. Graff (age 65). Mr. Graff has been a director since May 2013. Mr. Graff is Chairman, Chief Executive Officer and President of American Air Liquide Holdings, Inc., Executive Vice President of the Air Liquide Group overseeing the Americas and Asia, Chairman of Airgas and Chairman of Air Liquide’s Electronics World Business Line. Mr. Graff joined Air Liquide as President and CEO of Air Liquide USA LLC in April 2007. In May 2009, Mr. Graff was named a Corporate Vice President of Air Liquide S.A. and a member of the Executive Committee of the Air Liquide Group with responsibilities for North America and Safety and Industrial Systems Worldwide. In September 2009, he took on additional responsibilities and was named President and CEO of American Air Liquide Holdings, Inc. In January 2010, Mr. Graff’s responsibilities were expanded to include all of Air Liquide’s operations in the Western hemisphere (Americas). In April 2012, Mr. Graff’s responsibilities were expanded to include oversight of Air Liquide’s electronic business worldwide and he was named Chairman of the Electronics World Business Line. In January 2013, Mr. Graff was named a Senior Vice Present of the Air Liquide Group and, in April 2013, he was named Chairman of American Air Liquide Holdings, Inc. In February 2017, Mr. Graff was named Executive Vice President of Air Liquide S.A. and Chairman of Airgas Inc. Prior to joining Air Liquide, Mr. Graff began his career with Amoco Corporation and then worked for BP plc, where he last served as President and Chief Executive Officer of BP Polymers Americas from 2001 to 2004. Mr. Graff served as a director of The Lubrizol Corporation from 2009 until it was acquired by Berkshire Hathaway Inc. in 2011. Mr. Graff serves on the Board and the Executive Committee of the American Chemistry Council. He is also a member of the National Petroleum Council, the United States Investment Advisory Council and a principal of the American Energy Innovation Council. He is a member of the Greater Houston Partnership, a member of the Energy Forum of the Baker Institute at Rice University and serves on the Board of Trustees of the Illinois Institute of Technology, on the Engineering Advisory Council for Purdue University, on the Board of Directors of Junior Achievement of Southeast Houston, on the Board of Trustees for the George and Barbara Bush Foundation and on the Leadership Council for Houston Methodist Hospital. Mr. Graff holds an M.S. in Chemical Engineering from Purdue University, a B.S. in Chemical Engineering from the Illinois Institute of Technology, has studied business at the University of Chicago and has completed executive management programs at the Wharton School of the University of Pennsylvania, the University of Cambridge and the Stanford University Law School.

The Board has concluded that Mr. Graff should serve as a director of the Company based primarily on his extensive experience in the energy, chemicals and polymers industries and his experience as a chief executive officer, of a public company engaged in manufacturing.officer.

SECURITY OWNERSHIP OF DIRECTORS AND MANAGEMENT

The following table lists information about the number of shares of common stock beneficially owned by each director and each named executive officer listed in the summary compensation table included later in this Proxy Statement, and all of our directors and executive officers as a group. Shares of stock are “beneficially owned” by a person if the person

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directly or indirectly has or shares the power to vote or dispose of the shares, regardless of whether the person has any economic interest in the shares. A person also beneficially owns shares as to which the person has the right to acquire beneficial ownership within 60 days.

All information in the table is as of March 14, 201615, 2021 and is based upon information supplied by the directors and executive officers. Unless otherwise indicated in the footnotes and subject to community property laws where applicable, each of the stockholders named in the table has sole voting and investment power with respect to the shares indicated as beneficially owned.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS

The following table sets forth each person known to Westlake who is the beneficial owner of 5% or more of the outstanding shares of our common stock.

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COMPENSATION DISCUSSION AND ANALYSIS

A discussion and analysis of the Company’s executive compensation philosophy, objectives and underlying program is presented below. This discussion includes a review of the following:

Compensation Committee Oversight

The Board of Directors has established a Compensation Committee (the “Committee”) to review and provide oversight of the compensation programs of the Company and the compensation of the Principal Executive Officer (the “PEO”), the other officers named in the Summary Compensation Table (together with the PEO, the “Named Executive Officers” or the “NEOs”) and other employees designated as executive officers of the Company (collectively, the “Executives”).

Since Westlake is considered to be controlled by its principal stockholder under New York Stock Exchange rules, all Committee members are not required to be independent as defined by the listing standards of the New York Stock Exchange. The Committee is currently composed of fivesix independent board members, one of whom serves as the Committee’s chair, and three five non-independent members of the Board, one of whom is the PEO, one of whom is the Chairman of the Board, and the lastone of whom is the sister of the PEO and the Chairman of the Board.Board, one of whom is the son of the PEO and the nephew of the Chairman of the Board, and the last of whom is the son of the Chairman of the Board and the nephew of the PEO.

The Committee operates under the provisions of a charter and meets periodically throughout the year. The Committee’s duties include the following:

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In addition to referring to the Peer Group, Willis Towers Watson utilizes survey data from its proprietary general industry and chemical industry databases, including, but not limited to, the Willis Towers Watson CDB Executive Survey as well as the Korn Ferry Hay Group Chemicals Industry survey, and other relevant market information, that compare the compensation of executives at numerous companies in similar positions as the NEOs (the “Market Survey”). The Market Survey is used in conjunction with the Peer Group data (collectively, the “Reference Points”) to help validate the market findings and more specifically establish

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market compensation rates for positions for which there are limited Peer Group data and/or for positions that are not industry-specific and for which the Company would need to recruit on a broader basis (for instance, Chief Financial Officer). Finally, in establishing the target executive compensation, the Committee takes a total compensation view to include base pay, cash bonuses and long-term incentive and equity awards, so that as long as the composite total compensation of an NEO is competitive with the Reference Points, individual components may fall below or above the median of the Reference Points. In conducting its surveys for the Reference Points, Willis Towers Watson reports directly to the Committee on each component and on a composite total compensation basis.

The Committee meets annually in February to specifically address the compensation of the PEO, other NEOs and other Executives. During this meeting, the Committee reviews the achievement of the Company’s goals and objectives, including the Company’s performance relative to its competitors within the commodity chemical industry, including those direct competitors within the Peer Group, and the Committee reviews the Reference Points as well as other relevant factors established by the Committee for the PEO and the factors established by the PEO in setting and approving the other NEOs’ compensation. During this deliberation, the PEO is excused from the meeting to allow the other members of the Committee to deliberate independently regarding his compensation. During this annual review meeting, the PEO also presents his recommendations to the Committee regarding the compensation to be provided to the other NEOs and other Executives. The PEO and the Committee, after considering data from the Reference Points and other relevant factors, set the compensation for these Executives.

Compensation Philosophy and Program Objectives

The Company has designed and maintains a comprehensive executive compensation program as a means of:

Elements of the Program; Internal Pay EquityProgram

The Company’s executive compensation program contains a combination of both short-term and long-term elements designed to reward and encourage near-term goal accomplishment as well as to reward and encourage long-term strategic thinking and actions that benefit the Company and its stockholders.stockholders by aligning executive pay to performance. These combined elements, in tandem with employee benefits and a limited number of perquisites, form the basis of Westlake’s total compensation system. These elements have been chosen as the compensation components designed to allow the Company to adhere to the above stated compensation philosophy and program objectives which include remaining “market competitive” with its peers in the chemical industry and the broader market for executive talent. Each element has been allocated in the total compensation package in an attempt to find a balance between short-term and long-term rewards as well as cash and non-cash forms of payment. Further, the total compensation program seeks to place a significant amount of pay “at risk” through the use of variable pay elements.elements to align pay with performance. The mix of base salary and performance-based compensation (inclusive of annual bonus and long-term equity incentive compensation) is represented in the charts below. The Committee has determined that based on the Reference Points and their broad corporate-wide responsibilities, the PEO

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and the Chairman, as compared with other NEOs, should receive a higher portion of their total compensation from “at risk” components given their ability to influence Company performance and the desire of the Committee to further incentivize the PEO’s and the Chairman’s ongoing efforts to create value for the stockholders. The relative difference in pay between the PEO and the Chairman primarily reflects the difference in job scope and responsibility between the two positions and is further validated by the Reference Points data, which show that the PEO is typically the highest paid position. The relationship in pay among the other NEOs is driven by variation in job scope and level of responsibility, the Reference Points data, individual performance, internal equity and other factors as determined by the Committee as appropriate.

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Prior Votes on Executive Compensation

In approving the 20152020 compensation of the NEOs, the Committee considered the results of the advisory vote on the say-on-pay proposal proposals at the 20142017 and 2020 annual general meetingmeetings of stockholders, at which a substantial majority of the votes cast on the say-on-pay proposal proposals were voted in favor of the proposal.proposals. The Committee did not change its executive compensation approach based on the vote.votes. The Committee will continue to consider the outcome of the Company’s say-on-pay votes when making future compensation decisions for the NEOs. At the 20112020 annual meeting, a substantial majority of the votes cast on the advisory vote on the frequency of the say-on-pay proposal were voted in favor of holding that vote every three years. The Committee expects to hold another advisory vote on executive compensation in 2017.

Establishing Compensation Levels

On an annual basis as the Committee meets to set the target compensation for the PEO, other NEOs and other Executives, the Committee considers the responsibility and scope of the individual job assignments as well as the Executive’s job performance and achievements measured against a variety of goals and objectives. As a first step, the PEO provides his evaluation of each Executive based upon the achievement of goals and objectives unique to a business segment or a corporate assignment and an assessment of the Executive’s individual contribution and effort and a variety of managerial success factors. Next, the Committee may make its own assessment of each Executive based upon the interaction Committee members have had with the Executive throughout the year. Lastly, once the Committee considers all of these factors in tandem with the Reference Points, the Committee establishes the compensation target for each element of the total compensation program.

Base Pay—This element is the principal cash compensation component of the Company’s program and is designed to provide the Executive with a market-competitive minimum level of compensation. In setting base pay rates for 2015,2020, the Committee considered the Reference Points, the scope and range of responsibility, accountability and business impact of the position as well as current economic conditions to aid it in evaluating and matching the positions with the market and setting fair-market competitive base pay targets. In setting base pay rates for Executives, the Committee has determined that, based on the advice of its independent consultant, Willis Towers Watson, the base pay of the Executives can generally be considered as competitive if targeted to be within 90% to 110% of the 50th percentile of the market depending on the performance of the individual Executive, the magnitude of adjustments deemed necessary by the Committee to ensure retention of the Executive and the performance of the Company. The Committee also recognizes that market pricing is an inexact science and that base pay above or below that range may be required to meet market demand or to recognize individual performance or experience levels. The Committee does not set a specific fixed target percentage for any of the NEOs but generally works to set the base pay of each NEO to be within the range at its discretion based upon market and performance factors. Base pay is evaluated on an annual basis using then current market information, and the Committee may authorize an adjustment to:

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For additional information on the salaries paid to the PEO and the other NEOs during 2015,2020, see “Executive Compensation—20152020 Summary Compensation Table.” In February 2016,lieu of a salary increase for 2020, the Committee elected to issue to each of the NEOs a special, one-time grant of restricted stock units, which vested in February 2021, equivalent in value to what would have been provided as an increase to base salary, to further align the interests of our executives with those of our shareholders. In January 2021, the Committee elected to increase the base salary of Mr. Kearns from $618,000 to $680,000 in connection with his promotion to Executive Vice President and Chief Operating Officer. In February 2021, the Committee further elected to set the base salaries for the NEOs as follows: $985,000$1,167,000 for Mr. Albert Chao, $788,000$714,000 for Mr. James Chao, $525,000$641,000 for Mr. Bender $409,000and $554,000 for Mr. Buesinger and $393,000 for Mr. Kenner.Ederington. The salaries of Mr. Albert Chao, Mr. James Chao, Mr. Bender Mr. Buesinger and Mr. KennerEderington were increased from $953,000, $762,000, $500,000, $393,000$1,144,000, $700,000, $628,000 and $379,000,$543,000, respectively, after consideration of the Reference Points.

Cash Incentive Plans/Bonuses—For 2015,2020, the PEO, other NEOs and other Executives were eligible to be considered to receive payments under the Company’s Annual Incentive Plan (“AIP”) and Quarterly Incentive Plan (“QIP”). The AIP is designed to conform to the provisions of the Westlake Chemical Corporation 2013 Omnibus Incentive Plan, as amended and restated in 2017 (the “2013 Plan”). The Committee administers the AIP with respect to the Executives, and the PEO (or any other Executive to whom the PEO may delegate such authority) administers the AIP with respect to other participants. Awards under the AIP are intended to qualify as “qualified performance awards” under the 2013 Plan that comply with the rules applicable to

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performance-based compensation pursuant to Section 162(m) of the Internal Revenue Code. The bonus potential of the AIP and QIP plans has been designed to serve as a significant incentive for continuous improvement and to provide cash compensation opportunities that are competitive within the market with an emphasis on the Company’s peers within the chemical industry.

AIP.AIP. Under the terms of the AIP, a target bonus percentage is established by the Committee for the PEO, other NEOs and other Executives generally ranging from 30%35% to 100%130% of base pay (as of the end of the previous year) depending on the position, level and range of responsibility of the employee. The Committee uses the target bonuses as reference points but retains the discretion to award bonuses based on the specific factors described below with respect to individual NEOs. In establishing the target bonus, the Committee reviews the Reference Points with respect to the PEO and the PEO’s recommendations and the Reference Points with respect to the other NEOs. The Committee set the AIP target bonuses for 20152020 and 20162021 as follows (as a percentage of base pay):

The change in the AIP target for Mr. Kearns was made in connection with his promotion to Executive Vice President and Chief Operating Officer.

No bonus payment is authorized under the AIP unless one of the performance goals established by the Committee for the performance period is satisfied. For 2015,2020, the Committee approved the following threshold metrics for the AIP, any one of which must have been met in order to authorize bonus payments under the AIP for 2015:2020:

In February 2016,2021, the Committee reviewed the results of the Company with respect to these performance goals and certified that twoall of these three goals had been met for 2015,2020, as follows:

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The Committee then reviewed the contributions and performance of the PEO and each of the other NEOs during 20152020 and, in its discretion, awarded bonus payments under the AIP to the PEO and each of the other NEOs. Mr. Albert Chao was awarded a bonus payment equal to 292%155% of his target bonus and Mr. James Chao was awarded a bonus payment equal to 292%157% of his target bonus, in each case based on their leadership during the continued strong earningschallenges brought by COVID-19, hurricanes Laura and performance of the Company in increasingly difficult market conditionsDelta and the achievement of several strategic projects (suchgeneral economic environment in 2020, as well as the Westlake Chemical Partners LP acquisition of an additional 2.7% limited partner interest in Westlake Chemical OpCo LPfocus on safe and the Company’s acquisition of an additional 35.7% interest in Suzhou Huasu Plastics Co., Ltd.).efficient operations. The Committee awarded Mr. Bender a bonus payment equal to 303%162% of his target bonus in consideration of his leadership role in implementing effective cost controls and maintaining a strong balance sheet despite the challenges brought by COVID-19, hurricanes Laura and Delta and the general economic environment in connection with the previously mentioned strategic projects.2020. The Committee awarded Mr. BuesingerEderington a bonus payment equal to 289%155% of his target bonus based upon his leadership role during the challenges brought by COVID-19, hurricanes Laura and Delta, and the general economic environment in 2020, as well as his management of certain legal and organizational matters. The Committee awarded Mr. Kearns a bonus payment equal to 115% of his target bonus based upon the financial performance and continued strong competitive position of the vinyls business, as well aschemicals businesses and his leadership role during the integration of Vinnolit. The Committee awarded Mr. Kenner a bonus payment equal to 288% of his target bonus based uponchallenges brought by COVID-19, hurricanes Laura and Delta and the strong operational performance of the U.S. chemical plants.general economic environment in 2020.

In February 2016,2021, the Committee approved a set of metrics substantially similar to those used for the 20152020 AIP plan year, any one of which must be met in order to authorize bonus payments for the 20162021 AIP plan year.

The cash bonus payments are typically made in March of each year.

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QIP.QIP. The QIP is a short-term cash incentive designed for the general employee population, including the NEOs and the other Executives, and is paid to all eligible employees on a quarterly basis for the achievement of short-term operating goals for their respective departments, units or operations. For example, the targets in 20152020 for an operating unit under either the olefins or the vinyls business segment included a variety of operational and commercial goals, including production and sales volumes, raw material usage and yields, as well as goals to limit or reduce safety and environmental incidents and to improve product quality. The QIP award for the NEOs with corporate assignments (Messrs. Albert Chao, James Chao, Bender and Bender)Ederington) was based upon keeping operating expenses within budgeted amounts for the applicable corporate departments and a weighted average of the factors for each of the business segments. For 2015, there were dozens of these targets for each NEO, no single one ofThe NEOs are subject to the same metrics that apply to the general employee population, which was material.include safety, environmental, operating efficiency and cost/profitability metrics. All of the goals are established and weighted by management and approved by the PEO at the beginning of each year or when executive responsibilities change, and are measured each quarter to determine the level of goal achievement and the payment amount. Although the QIP results are measured and a payment is received each quarter, the QIP provides for a make-up provision at the end of the year so that if certain targets were not met in the previous quarters, but were met at the end of the year, the participants will be eligible to receive a make-up payment for having achieved the targets for the full year.

The goal-setting process includes the establishment of targets that seek to foster continuous improvement in all aspects of the Company’s operations and in any given year to focus on the most important elements facing the operations at the time. The targeted quarterly payment under these plans for 20152020 for each of the NEOs was 8% of quarterly eligible earnings. These target percentages reflect similar percentages for almost all similarly situated employees at Westlake. Payment is based upon the rate of actual goal achievement: in other words, if 60% of the quarterly targets were met, then 60% times 8% would be paid, or 4.8%. In all cases, however, the final payment is subject to the Company meeting a return on capital employed (“ROCE”) target which is specific only to the QIP and is established by the PEO at his discretion at the beginning of each Plan Year. The QIP ROCE target for 20152020 was 5.25%. In the event the ROCE target is met, 100% of the QIP payment will be authorized, subject to the achievement of the actual goals. If the ROCE target is not met but is above 0%, then a prorated QIP payment will be authorized, subject to the achievement of the actual goals. If the ROCE target is 0% or below, a payment of 25% of the QIP will be authorized, subject to the achievement of the actual goals. The full year results of the QIP for 20152020 for the NEOs is noted below:

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Long-Term Incentives (“LTI”)—A long-term equitystock-based and cash-based incentive program has been adopted by the Board of Directors to foster a long-term view of the business, assist in retaining and rewarding Executives for their efforts and achievements and provide management with an ownership interest in the Company to help to further align their actions with the interests of the stockholders. Under the terms of the 2013 Plan, the Company may grant Executives a variety of stock-based and cash-based compensation awards. In determining the targeted LTI award, the Committee utilizes the same deliberative process as earlier described for base pay and cash incentives. The Committee reviews the Reference Points and recommendations from Willis Towers Watson and the PEO, then sets a LTI target for each of the NEOs, which is a percentage of base pay based upon each NEO’s base pay as of the previous year end. As with other elements of the Company’s compensation program, the size of these awards is based upon the level and scope of the Executive’s job, the performance of the individual and competitive market forces. The Committee determined that to be competitive with relevant companies set forth in the Reference Points, the LTI targets for the PEO and other NEOs should be no less than 80% and no higher than 110% of the market 50th percentile for long-term incentives for similarly situated executives at companies set forth in the Reference Points. For more information on LTI awards granted to the NEOs in 2015,2020, please see “Executive Compensation—20152020 Grants of Plan-Based Awards.” After reviewing the Reference Points at meetings in February 20152020 and 2016,2021, the Committee set the LTI targets for Messrs. Albert Chao, James Chao, Bender, BuesingerEderington and KennerKearns as outlined below.

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The LTI targets (each as a percentage of base pay for an NEO) set for the PEO and the other NEOs by the Committee for 20152020 and 20162021 are as follows:

Changes in the LTI targets for Messrs. Bender and BuesingerEderington were made in consideration of the Reference Points data with respect to comparable positions. The change in the LTI target for Mr. Kearns was made in connection with his promotion to Executive Vice President and Chief Operating Officer.

The Committee granted the LTI awards using three separate components, each comprising one-third of the value of the overall award:

The Committee, after consultation with management and Willis Towers Watson, has chosen this program to recognize the unique characteristic of each award type. While all three types of awards provide Executives with an incentive to help grow the value of the Company and the corresponding value of the stock, options may experience more volatility over the term of the award, and the Executives may receive no compensation if the price of the Company’s shares never exceeds the exercise price of the options following vesting of the options. On the other hand, restricted stock unit awards put direct shares into the hands of management and give them a more direct line of sight to the potential value they might realize. In addition, the long-term performance cashstock unit award is designed to provide added incentive as an upside potential payment in cash based on the achievement of a performance target. Thus, theThe Committee believes the equal split of awards of stock options, restricted stock units and long-term cash performanceperformance-based awards provides an overall balanced award.

Non-Qualified Stock Options—Options—Under the provisions of the 2013 Plan, the Company may grant non-qualified stock options to executive and senior management personnel. The Board of Directors typically grants these awards annually during the first quarter of the year in conjunction with the first Board of Directors meeting of the year. The grant price for these awards is based upon the mean of the high and low market price for shares of the Company’s common stock on the date of the award as approved by the Board of Directors. All annual stock options granted by the Board of Directors to date have had a 10-year term with a three- or four-yearthree-year ratable vesting period. The Company has not made any post-award adjustments in grant dates or grant prices.

Restricted Stock Units—Units—As with stock options, the Board of Directors typically grants awards of restricted stock units annually during the first quarter of the year in conjunction with the first Board of Directors meeting of the year. Each

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restricted stock unit award granted by the Board of Directors represents a contingent right to one share of Westlake’s common stock and is scheduled to vest 100% at the end of a three-year period asperiod. In addition, after a means of strengthening the Company’s overall executive retention efforts. Historically, the Company granted restricted stock awards for this componentreorganization of the LTI awards. However, beginningcorporate reporting structure, in 2013, the Company decided to grantFebruary 2020, Mr. Ederington and Mr. Kearns were awarded special restricted stock unit awards of $500,000 and $650,000, respectively, which will vest in order to streamline administration.

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Long-Term Cash Performance Awards—Stock Unit Awards—The long-term cash performance stock unit awards granted in February 20152020 are subject to a three-year performance period beginning on January 1, 20152020 and ending on December 31, 2017.2022. The amount of cashperformance stock units received will be based upon either the Company’s total shareholder return compared with the total shareholder return of the Peer Group for 20152020 (threshold performance requires a relative total shareholder return rank of at least the 33rd percentile; target performance requires a rank of at least the 50th percentile; and maximum performance requires a rank of at least the 75th percentile) or the Company’s return on the cost of capital (threshold performance requires returns equal to at least 50% of the weighted average cost of capital (“WACC”); target performance requires a return equal to at least the WACC; and maximum performance requires a return equal to at least two times the WACC), whichever measure results in the greater payout.

If at least the threshold performance is attained, the long-term performance awards will be paid in cash after the Committee determines the performance level.

The Company granted long-term cash performance awards in February 2016 with terms and conditions substantially similar to the 2015 awards.

Stock Ownership, Pledging and Anti-Hedging Policy—In an effort to further align the interests of the Executives and the stockholders, the Committee has adopted a policy that requires the PEO, each other NEO and other key Executives, as well as directors, to retain 50% of any vested restricted stock and shares of common stock of the Company acquired through the vesting of restricted stock awards, restricted stock unit awards and performance stock unit awards, net of shares used to pay applicable taxes, until the total value reaches five times the annual base salary for Messrs. Albert Chao and James Chao, three times the annual base salary for certain other officers (including Messrs. Bender, BuesingerEderington and Kenner)Kearns), one times the annual base salary of other officers, and three times the annual cash retainer for directors, or until his or her employment or service, as the case may be, with the Company terminates. This policy also prohibits our directors and executives from shorting or hedging, or buying puts and calls with respect to, our securities, or entering into similar arrangements and requires directors and executives to provide notice prior to pledging our securities. None of our directors or executives currently pledges any of our securities. Equity awards to Executives, any shares of common stock issued under equity awards and any profits realized on the sale of such shares are subject to potential clawback or recoupment.

Perquisites—All —All Executives arewere eligible for a Company-paid membership in a local dining and/or athletic club and a Company-paid annual physical examination. These perquisites areexamination during 2020, which is provided as furthera means to attract and retain Executives, to provide Executives with access to facilities that may also be used for business entertainment and to promote personal health and wellness.

Post-Employment Programs—Executives are eligible for participation in the same retirement pension and post-retirement benefit programs as all employees within their respective business units. The Company does not provide any supplemental executive retirement or pension benefit.benefit for which these executives are eligible. The Company’s primary retirement benefit is the Westlake Savings Plan, a 401(k) defined contribution plan, and participating employees, including Executives, are eligible for a matching contribution from the Company based upon the plan provisions. Additionally, the Company provides an annual contribution to the plan for all eligible employees and Executives equal to 8% of their annualized base pay in 20152020 and 20162021 up to the IRS limits ($265,000285,000 for 20152020 and 2016)$290,000 for 2021).

Employment Agreements; Severance and Change-in-Control Arrangements—The Company does not have employment agreements with any of the NEOs; however, each Executive, including each of the NEOs, is typically provided an offer letter of employment containing the principal elements of the employment arrangement, including compensation. None of these offer letters currently contains a provision for payments upon a change in control.

Deferred Compensation Programs—The Company has no deferred compensation programs for which the Executives are eligible to participate except for the standard provisions of the Company’s 401(k) plan and provisions of Section 125 of the Internal Revenue Code whereby salary is reduced for taxation since the 401(k) contributions are made by employees on a pre-tax basis, thereby reducing their salary and taxable income.

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REPORT OF THE COMPENSATION COMMITTEE OF THE BOARD OF DIRECTORS

The following report has been submitted by the Compensation Committee of the Board of Directors:

The Compensation Committee of the Board of Directors has reviewed and discussed the Company’s Compensation Discussion and Analysis with management. Based on this review and discussion, the Compensation Committee recommended to the Board of Directors that the Compensation Discussion and Analysis be included in the Company’s proxy statement for its 20162021 annual meeting of stockholders, which is incorporated by reference in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2015,2020, each as filed with the Securities and Exchange Commission.

The information contained in this report shall not be deemed to be “soliciting material” or “filed” or incorporated by reference in future filings with the SEC, or subject to the liabilities of Section 18 of the Exchange Act, except to the extent that the Company specifically incorporates it by reference into a document filed under the Securities Act or the Exchange Act.

COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION

Messrs. Albert Chao, David Chao, James Chao and Dorothy C.John Chao and Ms. Jenkins are currently members of the Compensation Committee and are not “independent” as defined by the listing standards of the New York Stock Exchange. Michael J.Messrs. Graff, Max L. Lukens, R. BruceHaas, McCollum, Northcutt H. John Riley, Jr. and Robert T. BlakelySheets and Ms. Lubel are also currently members of the Compensation Committee. Under the corporate governance rules of the New York Stock Exchange, we are considered to be controlled by TTWF LP, so we are eligible for, and have elected to take advantage of, the exemption from the provisions of those rules requiring a compensation committee composed entirely of independent directors.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Based solely on a review of the copies of reports furnished to us during the year ended December 31, 2015 and written representations from our officers and directors, we believe all stock transaction reports required to be filed with the SEC under Section 16(a) of the Securities Exchange Act of 1934 in 2015 were timely filed by all directors, officers and beneficial owners of more than 10% of our common stock.

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EXECUTIVE COMPENSATION

The following tables provide information regarding the compensation awarded to or earned during 20152020 and, to the extent applicable, prior years, by the NEOs.

20152020 Summary Compensation Table

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The amounts include the following in 2014:2019:

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The amounts include the following in 2013:2018:

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20152020 Grants of Plan-Based Awards

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20152020 Outstanding Equity Awards at Fiscal Year-End