WLK Westlake Corporation

WESTLAKE CORPORATION

2801 Post Oak Blvd.

Houston, Texas 77056

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held on May 8, 2025

To the Stockholders:

The annual meeting of stockholders of Westlake Corporation (the “Company” or “Westlake”) will be held at Westlake Center, 2801 Post Oak Blvd., Houston, Texas 77056, on Thursday, May 8, 2025 at 9:00 a.m. local time for the following purposes:

The Board of Directors has fixed the close of business on March 10, 2025 as the record date for the determination of stockholders entitled to notice of, and to vote at, the annual meeting.

We 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 28, 2025, 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

Executive Vice President, Performance and Essential

Materials, General Counsel and Chief Administrative

Officer

Dated: March 28, 2025

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be Held on May 8, 2025:

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

WESTLAKE CORPORATION

2801 Post Oak Blvd.

Houston, Texas 77056

PROXY STATEMENT

For the Annual Meeting of Stockholders to be Held on May 8, 2025

GENERAL MATTERS

This Proxy Statement and the accompanying form of proxy are being furnished to the stockholders of Westlake Corporation (the “Company” or “Westlake”) on or about March 28, 2025 in connection with the solicitation of proxies by our Board of Directors for use at the annual meeting of stockholders to be held on Thursday, May 8, 2025 at 9:00 a.m. local time at Westlake Center, 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 unanimously recommends a vote:

(1) FOR the nominees for director listed in these materials and on the proxy; and

(2) FOR the ratification of the appointment of the Company’s independent registered public accounting firm.

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 10, 2025, 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 128,489,006 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, are not considered “routine” matters and, therefore, your broker will not have the discretionary authority to vote your shares on such matters 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.

An affirmative vote of a majority of the votes cast “for” or “against” the proposal 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 for the fiscal year ending December 31, 2025. 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 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,

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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 10, 2025, TTWF LP, our principal stockholder, and TTWFGP LLC, TTWF LP’s general partner, owned 72.3% 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. Roger A. Cregg, Michael J. Graff, Mark A. McCollum, R. Bruce Northcutt and 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 relationships do not preclude independence under the New York Stock Exchange rules, Mr. Graff, until July 2024, served as an executive officer of a company with which Westlake conducts business in the ordinary course.

EXECUTIVE SESSIONS

The Company’s Principles of Corporate Governance 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 three of the non-management directors (Mss. Catherine Chao and Carolyn Sabat and Mr. David Chao) are not independent, the Company’s Principles of Corporate Governance 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 Mark A. McCollum (chairman), Roger A. Cregg, Michael J. Graff, Kimberly S. Lubel, R. Bruce Northcutt and Jeffrey W. Sheets. Mr. Marius A. Haas served as a member of the Audit Committee until December 2024. 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. Cregg, Graff, McCollum, Northcutt and Sheets 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 2024. 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—Governance Documents.”

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The Compensation Committee

The Compensation Committee of the Board of Directors is currently comprised of R. Bruce Northcutt (chairman), Roger A. Cregg, Michael J. Graff, Kimberly S. Lubel, Mark A. McCollum and Jeffrey W. Sheets (i.e., all of the independent members of the Board of Directors). Mr. Marius A. Haas served as a member of the Compensation Committee until December 2024. The Compensation Committee’s primary functions include overseeing our executive compensation, director compensation and equity and performance incentive compensation plans and policies, including administering the Company’s policy for recovering erroneously awarded compensation. This Committee held five meetings in 2024. 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—Governance Documents.”

The Corporate Risk and Sustainability Committee

The Corporate Risk and Sustainability Committee of the Board of Directors is currently comprised of Michael J. Graff (chairman), Albert Y. Chao, Catherine T. Chao, David T. Chao, James Y. Chao, John T. Chao, Roger A. Cregg, Kimberly S. Lubel, Mark A. McCollum, R. Bruce Northcutt, Carolyn C. Sabat and Jeffrey W. Sheets (i.e., all of the members of the Board of Directors). Mr. Marius A. Haas served as a member of the Corporate Risk and Sustainability Committee until December 2024. 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 (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. In addition, as described in more detail below, this Committee assists the Board in discharging its oversight responsibility of the Company’s sustainability initiatives and policies. This Committee held four meetings in 2024. The Corporate Risk and Sustainability Committee charter is publicly available on our website at: http://www.westlake.com under “Investor Relations—Governance Documents.”

The Nominating and Governance Committee

The Nominating and Governance Committee is currently comprised of Jeffrey W. Sheets (chairman), Roger A. Cregg, Michael J. Graff, Kimberly S. Lubel, Mark A. McCollum and R. Bruce Northcutt (i.e., all of the independent members of the Board of Directors). Mr. Marius A. Haas served as a member of the Nominating and Governance Committee until December 2024. The Nominating and Governance Committee’s primary functions are (i) to identify individuals qualified to become directors of the Company, (ii) 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, (iii) to recommend changes to the size of the Board of Directors, (iv) to recommend committee assignments for directors, (v) to oversee the annual assessment of the performance of the Board of Directors and its committees, and (vi) to assess the adequacy of the Company’s corporate governance policies, practices and procedures and recommend any changes to the Board for approval. 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, diversity with respect to, among other things, level and type of career experience, gender, ethnicity, geographic location, and expertise, and commitment to acting in the best interests of the Company and its stockholders. This Committee held four meetings in 2024. 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—Governance Documents.”

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 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. A search firm retained by the Nominating and Governance Committee to identify and recruit potential candidates was utilized in the appointment of Mr. Cregg to the Board of Directors in December 2024. The Nominating and Governance Committee takes diversity, broadly defined to include race, 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 COMPOSITION

The Board of Directors believes that having a mix of directors with complementary qualifications, skills and expertise is essential to effectively discharging its oversight responsibility while advancing the Company’s long-term business strategy. The Nominating and Governance Committee and the Board each believe that the current composition of the Board reflects a group of highly talented individuals with diverse backgrounds, skills, professional and industry experience, and other personal qualities and attributes best suited to perform oversight responsibilities for the Company and its stockholders and to provide practical insights and varied perspectives. We have three women directors, two of whom are also racially-diverse, and four other racially-diverse directors on the Board.

BOARD LEADERSHIP STRUCTURE

We have separated the positions of executive chairman of the board, senior chairman of the board and chief executive officer. Currently, Mr. Albert Chao serves as our Executive Chairman of the Board, Mr. James Chao serves as our Senior Chairman of the Board and Mr. Jean-Marc Gilson serves as our President and Chief Executive Officer. Mr. James Chao served as Chairman of the Board and Mr. Albert Chao served as President and Chief Executive Officer until July 2024. Our Board has concluded that balance and varying experience and judgment are added to the leadership of the Board by having these positions filled by different persons.

Messrs. Albert Chao, our Executive Chairman of the Board, and James Chao, our Senior Chairman of the Board, are 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.

BOARD ROLE IN CORPORATE RISK OVERSIGHT

As previously described, our Board’s Corporate Risk and Sustainability Committee assists the Board of Directors in overseeing overall risks inherent in the operations of the Company and the control processes with respect to those risks (including, but not limited to, environmental, health, safety, sustainability and cybersecurity risks). Additionally, the 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 executive compensation, succession planning, and management development and personnel practices. 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

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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:

CYBERSECURITY

The Company maintains a comprehensive approach to cybersecurity and data protection, based on a risk-based, defense-in-depth strategy. We regularly assess industry best practices and standards and endeavor to implement them in our efforts to manage cybersecurity risk. We follow industry standard cybersecurity frameworks, including the National Institute of Standards and Technology’s Cybersecurity Framework to design, assess and update our cybersecurity strategy, controls and processes. Our focus is on protecting our highest-value information assets, which include manufacturing systems, financial systems, and confidential, personal, and private information.

To safeguard our networks and systems, we have a dedicated cybersecurity organization overseen by our Chief Information Security Officer, which operates within our information technology department overseen by the Chief Information Officer. Our cybersecurity organization employs multiple security controls, such as firewalls, spam protection, web filtering, endpoint detection and response software, controlled access, vulnerability management, redundancies, patching, and regular onsite and offsite backups. Our cybersecurity organization also uses a variety of processes to address cybersecurity threats related to the use of third-party technology and services, including pre-acquisition diligence, imposition of contractual obligations, and risk-based performance monitoring.

Both our Chief Information Officer and our Chief Information Security Officer have extensive experience in assessing and managing cybersecurity risks, including through decades of collective experience in information technology and cybersecurity roles of increasing responsibility both at the Company and in prior positions. We prioritize cybersecurity awareness among our employees and contractors through various training exercises, including formal programs and simulated phishing events. We maintain incident response plans, playbooks, and engage third-party cybersecurity firms for simulated cyberattacks and penetration testing to identify potential risks. We also have a third-party cybersecurity firm on retainer for incident assistance and response. Periodic internal self-assessments are conducted by our cybersecurity organization using the National Institute of Standards and Technology Cybersecurity Framework.

From time to time, we experience cybersecurity threats and attempted breaches and other incidents. We classify and track these events based on significance and implement remediation actions that we consider appropriate to address the risks relating to such incidents. Although we have not experienced material impacts to our business strategy, results of operations or financial condition from any such incidents in the past three years, we cannot guarantee that a material incident will not occur in the future. See “Failure to adequately protect critical data and technology systems could materially affect our operations” under Item 1A. Risk Factors in our Annual Report on Form 10-K.

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PROPOSAL 1—ELECTION OF CLASS III DIRECTORS

Our 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 was nominated by our Nominating and Governance Committee, are proposed for election in Class III, to serve until the annual meeting of stockholders in 2028, or until their successors are elected and qualified:

Ms. Sabat and Messrs. Albert Chao, David Chao and Graff are incumbent Class III directors. Unless instructed otherwise, the proxies will be voted for the election of the four 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 UNANIMOUSLY RECOMMENDS A VOTE FOR

THE ELECTION OF THESE NOMINEES AS CLASS III DIRECTORS.

NOMINEES FOR ELECTION AS CLASS III DIRECTORS

Albert Y. Chao (age 75). Mr. Chao has been our Executive Chairman of the Board since July 2024 and a director since June 2003. From May 1996 to July 2024, Mr. Chao served as President and, from July 2004 to July 2024, he served as our Chief Executive Officer. In addition, Mr. Chao has been a director of Westlake Chemical Partners GP LLC, a wholly owned subsidiary of ours and the general partner of Westlake Chemical Partners LP, since its formation in March 2014, its Executive Chairman of the Board since July 2024 and served as its President and Chief Executive Officer from March 2014 to July 2024. In 1985, Mr. Chao assisted his father, T.T. Chao, and his brother, James Y. Chao, in founding Westlake. 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. He is the brother of James Y. Chao, father of John T. Chao and Carolyn C. Sabat, and uncle of David T. Chao and Catherine 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 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.

David T. Chao (age 48). 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. Mr. Chao has also served as Chief Executive Officer of Tempest Peak Management LLC since December 2022. 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, brother of Catherine T. Chao, and the cousin of John T. Chao and Carolyn C. Sabat. 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 69). Mr. Graff has been a director since May 2013. Mr. Graff is the former Chairman and Chief Executive Officer of American Air Liquide, Inc. and former Executive Vice President of the Air Liquide Group. Mr. Graff joined Air Liquide as President and CEO of Air Liquide USA LLC in April 2007. In May 2009, Mr. Graff was

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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., took on additional responsibilities for Air Liquide’s operations in Asia and was named Chairman of Airgas Inc. In September 2022, Mr. Graff took on additional responsibilities as Chairman and CEO of Air Liquide’s Global Engineering and Construction business. In September 2023, Mr. Graff stepped down as Chairman and CEO of American Air Liquide Holdings, Inc., continuing as Chairman and CEO of American Air Liquide. In July 2024, Mr. Graff stepped down from his roles as Chairman and CEO of American Air Liquide, as Executive Vice President of the Air Liquide Group and all other executive responsibilities. Mr. Graff retired from Air Liquide on January 1, 2025. 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 previously served as Vice Chairman and chair of the Executive Committee of the American Chemistry Council, a principal of the American Energy Innovation Council, a member of the National Petroleum Council and a member the United States Investment Advisory Council, chairing the Committee on Competitiveness for the U.S. Department of Commerce. He is a member of the Energy Forum of the Baker Institute at Rice University and serves as Vice Chairman on the Board of Trustees of the Illinois Institute of Technology, on the Engineering Advisory Council for Purdue University, as Vice Chairman of the American Institute of Chemical Engineers’ Foundation, 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.

Carolyn C. Sabat (age 45). Ms. Sabat has been a director since May 2023. Ms. Sabat is the Managing Director – Investments for JADEC, LLC, an affiliate of our principal stockholder, a position she has held since June 2017. Ms. Sabat is also a Manager of Tanglewood Property Management Company, an affiliate of our principal stockholder, a position she has held since September 2017. Ms. Sabat began her career with The Goldman Sachs Group, Inc. in July 2001, eventually serving as Vice President for Asset Management and ending her tenure as Managing Director in May 2017. She is the daughter of Albert Y. Chao, the sister of John T. Chao, the niece of James Y. Chao, and the cousin of David T. Chao and Catherine T. Chao. Ms. Sabat holds a bachelor’s degree in psychology from Princeton University.

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

CLASS I DIRECTORS

Catherine T. Chao (age 47). Ms. Chao has been a director since May 2023. Ms. Chao has been the director and co-founder of Tuyo Development since 2019 and a founding partner of Grains of Salt since 2016. From 2007 to 2013, Ms. Chao was a project architect with Greg Yang Design and, from 2008 to 2013, she was an adjunct professor of the School of Constructed Environments at Parsons The New School of Design. In addition, since 1997, Ms. Chao has served in various roles at Tanglewood Property Management Company, an affiliate of our principal stockholder, and was appointed a Manager of Tanglewood Property Management Company in September 2017. She is the daughter of James Y. Chao, the sister of David T. Chao, the niece of Albert Y. Chao, and the cousin of John T. Chao and Carolyn C. Sabat. Ms. Chao holds a bachelor’s degree in product design from Stanford University, a Masters of Architecture from the Rhode Island School of Design, and an MBA and a Masters in Urban Planning from Columbia University. Ms. Chao is a registered architect in New York and Oregon, a member of the American Institute of Architects and a member of the American Planning Association.

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

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Roger A. Cregg (age 68). Mr. Cregg has been a director since December 2024. Mr. Cregg served as President, Chief Executive Officer and Director of AV Homes, Inc., from December 2012 until its sale to Taylor Morrison Homes in October 2018. From August 2011 through November 2012, he served as Senior Vice President of Finance and Chief Financial Officer of The ServiceMaster Company. He served as Executive Vice President and Chief Financial Officer of PulteGroup, Inc. (formerly known as Pulte Homes, Inc.) from May 2003 to May 2011; and as Senior Vice President and Chief Financial Officer of PulteGroup, Inc. from January 1998 to May 2003. Mr. Cregg also served as Executive Vice President and Chief Financial Officer of Zenith Electronics Corporation from 1996 to 1998; Vice President and Chief Financial Officer of Sweetheart Cup Company, Inc. from 1990 to 1996; and Vice President of Mead Corporation from 1989 to 1990. Mr. Cregg began his career at Continental Can Company, where he held a variety of accounting, finance, and administration roles. Mr. Cregg has served on the Board of Directors of Comerica Incorporated since December 2006, the Board of Directors of Sterling Infrastructure Inc. since May 2019 and the Board of Directors of Minto Group since July 2024. Previously, Mr. Cregg served on the Board of Directors of the Federal Reserve Bank of Chicago, Detroit Branch, from January 2004 to December 2009. Mr. Cregg received a bachelor’s of science degree in accounting from Northeastern University and an M.B.A from J.L. Kellogg Graduate School of Management at Northwestern University.

The Board has concluded that Mr. Cregg should serve as a director of the Company based primarily on his experience in the homebuilder industry and his leadership experience as chief executive officer and chief financial officer of public companies.

Kimberly S. Lubel (age 60). 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, the Board of Directors of the Southwest Research Institute since 2019, the Board of Directors of Arcosa, Inc. since November 2021, and the Board of Directors of Inspire Trust Company, N.A. since January 2022. Previously, Ms. Lubel served on the Board of Directors of WPX Energy Inc. from December 2011 through January 2021. Since 2022, Ms. Lubel has been an executive coach and independent consultant with the Exco Group. Ms. Lubel holds bachelor’s of arts degrees 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 67). 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 has served on the Board of Directors of Chord Energy Corporation since May 2024 and of Schlumberger Limited since October 2019. Mr. Sheets was a director of Enerplus Corporation from December 2017 until its acquisition by Chord Energy Corporation in May 2024 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 II DIRECTORS

James Y. Chao (age 77). Mr. Chao has been our Senior Chairman of the Board since July 2024 and became a director in June 2003. From July 2004 to July 2024, Mr. Chao served as Chairman of the Board and, from May 1996 to July 2004, he served as Vice Chairman. In addition, Mr. Chao has been a director of Westlake Chemical Partners GP LLC since its formation in March 2014, its Senior Chairman of the Board since July 2024 and served as its Chairman of the Board from July 2014 to July 2024. 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,

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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. He is the brother of Albert Y. Chao, father of David T. Chao and Catherine T. Chao, and uncle of John T. Chao and Carolyn C. Sabat. Mr. Chao received his B.S. degree from the Massachusetts Institute of Technology and an M.B.A. from Columbia University.

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 48). Mr. Chao has been a director since August 2018. Since July 2024, Mr. Chao has served as Senior Vice President and Managing Director of Westlake Innovations, Inc. (one of our subsidiaries) and from March 2021 to July 2024, Mr. Chao was its Vice President and Managing Director. 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, the brother of Carolyn C. Sabat, and the cousin of David T. Chao and Catherine 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 66). 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. Mr. McCollum has served on the Board of Directors of Seadrill Limited since February 2022 and the Board of Directors of Momentive Performance Materials, Inc. since December 2024. He previously served on the Board of Directors of Marathon Oil Corporation from December 2022 until its acquisition by ConocoPhillips in November 2024 and the Board of Directors of Archrock, Inc. from 2002 to July 2018. He also currently serves on the Board of Trustees for Baylor College of Medicine, the Board of Directors for the Baylor St. Luke’s Medical Center joint venture and the Board of Directors of 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 as a senior executive and in the field of financial accounting.

R. Bruce Northcutt (age 65). Mr. Northcutt has been a director since May 2013. Mr. Northcutt was a partner of Navitas Midstream Partners, LLC from November 2013 and the Chairman of the Board, Chief Executive Officer and President of its manager, Navitas Midstream Management, LLC, from May 2014 until Navitas’ acquisition by Enterprise Products Partners L.P. in February 2022. 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 served on the Board of Directors of Ball Ventures LLC from February 2023 until March 2025. Mr. Northcutt holds a 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.

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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.

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 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 10, 2025 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.

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS

The following table sets forth each person known to Westlake who is a 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 six independent board members, one of whom serves as the Committee’s chair.

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

The Committee may delegate its authority to subcommittees consisting of one or more members as it deems appropriate. The Committee has delegated its administrative duties with respect to equity award administration and processing (excluding granting authority) under the Omnibus Incentive Plan to certain authorized officers of the Company.

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External Advisors

To assist the Committee in respect of its oversight responsibilities, the Committee periodically utilizes the services of independent third-party compensation consultants to conduct compensation surveys and determine compensation trends, analyze and assess the Company’s compensation systems and programs, review current legal, accounting and administrative matters associated with executive compensation and offer opinions as to the effectiveness and competitiveness of the program. For 2024, the Committee directly engaged the services of Willis Towers Watson as a compensation consultant to advise the Committee on executive compensation matters. Willis Towers Watson assists the Committee by providing comparative market data on compensation programs and practices of peer competitors, the broader-based chemical and building products industries and general industry. Willis Towers Watson also assists the Company with general compensation consultation regarding employees other than the NEOs. In 2024, the Company paid Willis Towers Watson approximately $162,000 for compensation advisory services and approximately $2.1 million for other services (primarily related to administration of the Company’s legacy defined benefit retirement plans). The decision to engage Willis Towers Watson for the non-executive compensation services was determined by management and approved by the Committee. In February 2025, the Committee assessed whether the work of Willis Towers Watson for the Company during 2024 raised any conflict of interest and concluded that no conflict of interest exists.

The Deliberative Process

In establishing targeted levels of executive compensation, the Committee has selected a set of peer group companies (the “Peer Group”) from among companies of relative comparable size to the Company, with executive positions of similar scope and responsibility, and from among companies with which the Company may compete for executive talent. With the assistance of Willis Towers Watson, the Committee reviews the Peer Group on a regular basis. To validate current peers and identify potential new peer companies, Willis Towers Watson conducts a comprehensive review using both objective and qualitative criteria that the Committee deems to be appropriate, including recent developments with current peer companies (e.g., merger and acquisition activity and changes in financial performance), revenue, industry classification, market capitalization and other financial data, peers of peers analysis, business and product portfolios, peers as identified by proxy advisory firms such as ISS and Glass Lewis, and business and labor market competitors, with an overall objective of achieving approximately a median ranking for Westlake within the Peer Group.

The following companies from both the chemicals and building products industries made up the Peer Group as adopted by the Committee for purposes of determining compensation for 2024 (the “2024 Peer Group”):

As disclosed in last year’s proxy statement, in November 2023, as part of its annual evaluation process, and upon recommendation by Willis Towers Watson, the Compensation Committee determined, and the Board of Directors agreed, the 2024 selected Peer Group would be updated to achieve an approximately median ranking for the Company relative to the peer group. Going forward, the Committee will continue to evaluate and make changes in the Peer Group as warranted to reflect changes in the size, business profile and publicly-listed status of the companies to help ensure that companies comparable in size and business profile are included and continue to be appropriate for the compensation decision-making process.

In addition to referring to the Peer Group, Willis Towers Watson utilizes survey data from its proprietary compensation databases, including, but not limited to, the Willis Towers Watson CDB Executive Survey, and other relevant market information. These surveys compare the compensation of executives at numerous companies to 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 market compensation rates for positions with limited Peer Group data and/or for positions that are not industry-specific and for which the Company would

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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 incentives, so that as long as the composite total compensation of a 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 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 Economic Value Added (defined as the net operating profit after taxes in relation to capital employed, as described in more detail below) and performance relative to its competitors within the chemical and building products industries, including those competitors within the Peer Group, the Reference Points and other relevant factors established by the Committee. During this deliberation, the PEO is excused from the meeting to allow 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

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 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 and building products industries 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 to align pay with performance. The mix of base salary and performance-based compensation (inclusive of annual bonus, quarterly 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, the Executive Chairman and the Senior 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 Chairmen’s ongoing efforts to create value for the stockholders. The relative difference in pay between the PEO and the Chairmen primarily reflects the difference in job scope and responsibility between the two types of 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 2024 compensation of the NEOs, the Committee considered the results of the advisory vote on executive compensation (the “say-on-pay proposal”) at the 2023 annual meeting of stockholders, at which more than 96% of the votes cast on the say-on-pay proposal were voted in favor of the proposal. The Committee did not change its executive compensation approach based on the 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 2023 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.

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, other than himself, 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 2024, 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:

In connection with his appointment as President and Chief Executive Officer, the Committee set Mr. Gilson’s annualized 2024 base salary to $1,250,000. Effective as of July 15, 2024, Mr. Albert Chao’s base salary was decreased from $1,301,000 to $1,019,000 in connection with his transition from President and Chief Executive Officer of the Company to Executive Chairman of the Board.

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For additional information on the salaries paid to each individual who served as the PEO and the other NEOs during 2024, see “Executive Compensation—2024 Summary Compensation Table.” In February 2025, the Committee elected to set the base salaries for the NEOs as follows: $1,060,000 for Mr. Albert Chao, $1,300,000 for Mr. Gilson, $785,000 for Mr. Bender, $681,000 for Mr. Buesinger and $764,000 for Mr. Ederington. The salaries of Mr. Albert Chao, Mr. Gilson, Mr. Bender, Mr. Buesinger and Mr. Ederington were increased from $1,019,000, $1,250,000, $755,000, $655,000 and $735,000, respectively, after consideration of the Reference Points. The base salary of Mr. James Chao was decreased from $1,019,000 to $530,000 in connection with his transition to Senior Chairman of the Board and continued management of the Company as a member of its executive team.

Cash Incentive Plans/Bonuses—For 2024, each individual who served as the PEO, and the 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 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. The Senior Vice President, Human Resources administers the QIP. 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 and building products industries.

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 35% to 120% of base pay (as of the end of the performance period) depending on the position, level and range of responsibility of the employee. In establishing the target bonus percentage, 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. Mr. Albert Chao’s AIP target bonus percentage was decreased from 135% to 105% in July 2024 in connection with his transition from President and Chief Executive Officer of the Company to Executive Chairman of the Board. Pursuant to the terms of the AIP, Mr. Albert Chao’s AIP for 2024 will be calculated using the 105% target bonus percentage. The Committee set the AIP target bonus percentages for 2024 and 2025 as follows (which represent a percentage of base pay, the dollar value of which product is referred to herein as the “target bonus”):

Each year, in determining the bonuses to be awarded under the AIP, the Committee considers the performance of the Company, as well as the contributions of the individual NEOs and seeks to reward and encourage strategic thinking and actions that benefit the Company and its stockholders in the long-term.

The Committee approves threshold performance goals for (1) total shareholder return (“TSR”), (2) a return on capital measure based on an economic value added (“EVA”) rate of return (“EVA rate of return”) and (3) selling, general and administrative expenses (“SG&A”), each as described below. No bonus payment is authorized under the AIP unless one of the threshold performance goals established by the Committee for the performance period is satisfied. For 2024, 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 2024:

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In February 2025, the Committee reviewed the results of the Company with respect to these performance goals and certified that all of these goals had been met for 2024, as follows:

In February 2025, the Committee approved a set of threshold performance goals substantially similar to those used for the 2024 AIP plan year, any one of which must be met in order to authorize bonus payments for the 2025 AIP plan year.

After it is determined that at least one of the three threshold performance measures has been met, the Committee’s determination as to the amount of bonus awarded is significantly influenced by the EVA and the EVA rate of return. EVA and the EVA rate of return are solely measures used by the Company under its compensation programs. They are not the same as the corresponding accounting measures calculated in accordance with U.S. GAAP for financial reporting purposes and are not intended to reflect the Company’s performance for any purpose other than determination of bonuses awarded under the AIP and the amount of performance stock units earned.

NOPAT is adjusted to account for any amortization of intangibles, acquisition-related integration and transaction costs, and adjustments associated with acquisitions, impairment and restructuring costs (together, “non-operating impacts”) amortized over a period commensurate with the period which the Company realizes benefits, and noncontrolling interests.

Capital employed represents the Company’s total assets minus cash, restricted cash, current liabilities (but excluding the current portion of long-term debt) and pensions and other post-retirement benefits. Capital employed is adjusted to remove the impact of significant capital projects, non-controlling interests, the difference between an acquired company’s opening balance sheet and the purchase price for such acquired company, any impact based on the Company’s actual taxes paid as compared to the long-term expected cash tax rate used for NOPAT and adding back historical adjustments to NOPAT based on non-operating impacts.

The established performance metric for purposes of determining the bonus multiple that factors into final corporate AIP bonus calculations is the EVA rate of return. This achieved EVA rate of return is then compared to the Company’s estimate of its weighted average cost of debt and equity capital, which generally has been 8.75%. The comparison between the achieved EVA rate of return, relative to the capital charge of 8.75%, results in the corporate EVA bonus multiple set forth in the schedule below:

The EVA rate of return for 2024 was 7.5%, which resulted in a corporate EVA bonus multiple of approximately 0.86X.

For each individual AIP participant, the EVA bonus multiple is weighted depending on the corporate results or strategic business unit in which the participant belongs. For Messrs. A. Chao, J. Chao, Gilson, Bender and Ederington, their EVA bonus is 100% of the corporate EVA bonus multiple. For Mr. Buesinger, his EVA bonus multiple is weighted between the corporate EVA bonus multiple and segment EVA bonus multiple, which is calculated using a similar methodology as the corporate EVA bonus multiple.

In addition, for each individual AIP participant, the EVA bonus multiple is then adjusted between 80% and 120% based on individual performance factors, including attainment of goals, personal contribution and effort and managerial success factors. Goals and managerial success factors touch on several areas, including, but not limited to, safety, financial results, operational performance, and sustainability. The EVA bonus multiple, as adjusted for individual performance, is the final bonus multiple for each NEO’s final declared bonus for 2024.

In order to moderate the cyclical nature of the industries in which the Company operates, the Committee utilizes a “banking” approach that averages the EVA bonus multiple over several years by carrying two-thirds of each NEO’s EVA bonus multiple forward to the next year. Each NEO’s final bonus payment for the current plan year consists of one-third of the sum of their carried over EVA bonus multiples from prior years and the final declared bonus for the current year.

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The Committee then reviewed the EVA bonus multiples of the various business units, segments, and Westlake as a whole, taking into account the cyclical nature of our business and current market conditions, as well as the contributions and performance of the PEO and each of the other NEOs during 2024 and awarded bonus payments under the AIP to the PEO and each of the other NEOs. Mr. Albert Chao was awarded a final bonus payment equal to 167% of his target bonus, Mr. James Chao was awarded a bonus payment equal to 167% of his target bonus, and Mr. Gilson was awarded a final bonus payment equal to 45% of his target bonus, in each case based on their leadership in achieving overall earnings stability despite soft economic conditions in the global markets through the expansion and diversification of our businesses, their leadership role in achieving several strategic initiatives, their focus on safe and efficient operations and the transition of our succession plans. Mr. Gilson’s final bonus was pro-rated to reflect the number of days that he served as our PEO during 2024. The Committee awarded Mr. Bender a final bonus payment equal to 174% of his target bonus in consideration of the performance of the business and his leadership role in implementing effective cost controls, maintaining a strong balance sheet and pursuing strategic initiatives. The Committee awarded Mr. Buesinger a final bonus payment equal to 207% of his target bonus based upon record financial and operational performance of the Housing and Infrastructure Products segment and various initiatives including efforts to integrate enterprise-wide information systems. The Committee awarded Mr. Ederington a final bonus payment equal to 172% of his target bonus based upon his leadership of the Performance and Essential Materials segment during challenging economic conditions in the global markets, achieving various strategic initiatives, as well as his leadership role in the transition of our succession plans. The cash bonus payments are typically made in March of each year.

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. The Company operates more than two hundred quarterly incentive plans, each having individual targets designed to encourage the achievement of short-term operating goals for the respective functional group or operational unit. For example, the targets in 2024 for an operating unit under either the Performance and Essential Materials or the Housing and Infrastructure Products 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. Employees may participate in one or more quarterly incentive plan, depending on the role they perform for the Company. The QIP award for the NEOs was based upon a weighted average of each of the operational and plant level quarterly incentive plans, as well as management of SG&A expenses. The NEOs are subject to the same metrics that apply to the general employee population, which 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 2024 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 an EVA rate of return target that is specific to the QIP and is established by the PEO at his discretion at the beginning of each Omnibus Incentive Plan Year. The EVA rate of return target, under the QIP, for 2024 was 5.25%. The EVA rate of return under the QIP is calculated in the same manner as EVA rate of return under the AIP, as described above. The following table illustrates the effect of meeting the target level EVA rate of return, but in all cases the actual payout level under the QIP is subject to the achievement of the actual goals:

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In 2024, the EVA rate of return under the QIP was 7.5% and no adjustments as a result of such achievement were made because results exceeded the 5.25% target. The full year results of the QIP for 2024 for the NEOs is noted below:

Long-Term Incentives (“LTI”)—A long-term stock-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 Omnibus Incentive 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 then sets an 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 2024, please see “Executive Compensation—2024 Grants of Plan-Based Awards.” Effective as of July 2024, Mr. Albert Chao’s LTI target was decreased from 550% to 400% for LTI grants made beginning in 2025, in connection with his transition from President and Chief Executive Officer of the Company to Executive Chairman of the Board. In connection with his appointment as President and Chief Executive Officer in July 2024, Mr. Gilson was awarded, as a sign-on bonus, a special restricted stock unit award with an aggregate grant date fair value of $3,000,000, which will vest in three years. Mr. Gilson did not receive any other 2024 LTI awards.

The LTI targets (each as a percentage of base pay) set by the Committee for 2024 and 2025 are as follows:

Changes in the LTI targets for Messrs. Albert Chao, Gilson, Bender, Buesinger and Ederington, were made in consideration of the Reference Points data with respect to comparable positions.

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 performance stock unit award is designed to provide added incentive based on the achievement of a performance target. The Committee believes the equal split of awards of stock options, restricted stock units and performance-based awards provides an overall balanced award.

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Non-Qualified Stock Options—Under the provisions of the Omnibus Incentive Plan, the Company may grant non-qualified stock options to employees, including executive and senior management personnel. The Board of Directors typically grants these awards annually during the first quarter of the year in conjunction with its regularly-scheduled meeting held in February of each 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-year ratable vesting period. The Company has not made any post-award adjustments regarding grant dates or grant prices.

Restricted Stock 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 its regularly-scheduled meeting held in February of each year. Each restricted stock unit award granted by the Board of Directors represents a contingent right to receive one share of Westlake’s common stock and is scheduled to vest 100% at the end of typically, a three-year period, and occasionally a shorter or longer period. In connection with his appointment as President and Chief Executive Officer in July 2024, Mr. Gilson was awarded, as a sign-on bonus, a special restricted stock unit award with an aggregate grant date fair value of $3,000,000, which will vest in three years.

Performance Stock Unit Awards— As with stock options and restricted stock units, the Board of Directors typically grants awards of performance stock units annually during the first quarter of the year in conjunction with its regularly-scheduled meeting held in February of each year. The performance stock unit awards granted in February 2024 are subject to a three-year performance period beginning on January 1, 2024 and ending on December 31, 2026. The amount of performance stock units received will be based upon either the Company’s total shareholder return compared with the total shareholder return of the 2024 Peer Group (“Relative TSR”) (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 EVA bonus multiple based on the EVA rate of return being calculated in the same manner as described in “Cash Incentives Plan/Bonuses – AIP” (threshold performance requires an average EVA bonus multiple of at least 0.5X; target performance requires an average EVA bonus multiple of at least 1X; and maximum performance requires an average EVA bonus multiple of at least 2X), whichever measure results in the greater payout.

If at least the threshold performance is attained, the performance awards will be paid after the Committee determines the performance level.

The performance stock unit awards that were granted in February 2022, for the plan period January 1, 2022 through December 31, 2024, achieved a payout of 185.6%, based on a relative TSR rank of 71.4%, exceeding the target but not reaching the maximum performance rate.

Stock Ownership, Pledging and Anti-Hedging Policy—In an effort to further align the interests of the Executives and stockholders, the Committee has adopted a policy applicable to the PEO, each other NEO and other key Executives, as well as directors, which requires each such person to retain 100%, 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 six times the annual base salary for Messrs. Albert Chao, James Chao and Gilson, three times the annual base salary for certain other officers (including Messrs. Bender, Buesinger and Ederington), one times the annual base salary of other executives, and five 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 pledge 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 in accordance with the Company’s policy for recovering erroneously awarded compensation.

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Perquisites—All Executives were eligible for a Company-paid annual physical examination during 2024, which is provided as a means to promote personal health and wellness.

Retirement Benefit Programs

Executives are eligible for participation in the same retirement benefit programs as all corporate employees. The Company does not provide any supplemental executive retirement or pension 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 eligible employees and Executives equal to 8% of their annualized base pay up to the IRS limits ($345,000 for 2024 and $350,000 for 2025).

Employment Agreements; Termination or Change-in-Control Arrangements

Employment Agreements—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.

Termination or Change-in-Control Arrangements— Equity award agreements under the Omnibus Incentive Plan contain provisions that provide for certain accelerated vesting benefits in the event of termination by reason of death, normal retirement or in some cases, a termination without cause. Additionally, the AIP provides for the payment of a prorated bonus and certain banked amounts in the event of termination by reason of death, permanent disability, normal retirement or an approved reduction-in-force. In 2023, the Company incorporated change in control provisions into the AIP and Omnibus Incentive Plan, following shareholder approval, that provide for pro-rated vesting on a qualifying termination of employment within a twenty-four-month period following a change in control for awards that are assumed or replaced with equivalent awards. Such provisions provide for pro-rated double-trigger vesting and would result in full vesting in connection with a change in control if such awards were not assumed or replaced with equivalent awards. These provisions are intended to ensure the engagement of key employees in the event of disruptive circumstances resulting from a change in control, while being mindful of market practices relating to change in control protections. For additional information on termination and change in control provisions, see: “2024 Potential Payments Upon Termination or Change in Control” below.

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.

Recovery of Erroneously Awarded Compensation

In November 2023, the Committee recommended, and the Board of Directors approved, a policy for recovering erroneously awarded compensation, or “clawback” policy, applicable to executive officers. The policy implements the incentive-based compensation recovery provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 as required under the listing standards of the New York Stock Exchange, and requires recovery of incentive-based compensation received by current or former executive officers during the three fiscal years preceding the date it is determined that the Company is required to prepare an accounting restatement, including to correct an error that would result in a material misstatement if the error were corrected in the current period or left uncorrected in the current period. The amount required to be recovered is the excess of the amount of incentive-based compensation received over the amount that otherwise would have been received had it been determined based on the restated financial measure.

COMPENSATION COMMITTEE REPORT

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 2025 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, 2024, each as filed with the Securities and Exchange Commission.

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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. Cregg, Graff, McCollum, Northcutt and Sheets and Ms. Lubel (i.e., all of the independent members of the Board of Directors) served as members of the Compensation Committee for the fiscal year ended December 31, 2024. Mr. Haas served as a member of the Compensation Committee until December 2024. The Company and/or its affiliates purchase and lease various products from American Air Liquide, Inc. and its subsidiaries (collectively, “Air Liquide”), of which Mr. Graff served as Chairman and Chief Executive Officer until July 2024. In 2024, the Company paid these affiliates of Air Liquide approximately $45 million and sold certain industrial gases and utilities to Air Liquide in the amount of approximately $12 million.

EXECUTIVE COMPENSATION

The following tables provide information regarding the compensation awarded to or earned during 2024 and, to the extent applicable, prior years, by the NEOs.

2024 Summary Compensation Table

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2024 Option Exercises and Stock Vested