KAISER ALUMINUM CORP

General

We have a diverse and highly independent board of directors. Our board of directors currently has 10 members, consisting of our CEO and nine independent directors.

Our current directors are:

• Ms. Sebastian will not stand for reelection at the Annual Meeting.

Our board of directors represents a breadth of experience and diversity in perspective and background, as reflected in the summary of their collective qualifications below. Additionally, our directors have a broad range of tenures, from less thanone year to approximately 18 years of service, with an average tenure of approximately seven years. We believe this diversity balances institutional knowledge and experience with new perspectives and ideas.

The table below sets forth the knowledge, skills or board experience, demographics and board tenure of our directors as of April 28, 2025:

Our amended and restated certificate of incorporation and bylaws provide for a classified board of directors consisting of three classes. The term of our Class I directors expires at the Annual Meeting; the term of our Class II directors will expire at the 2026 annual meeting of stockholders; and the term of our Class III directors will expire at the 2027 annual meeting of stockholders.

Board Refreshment and Director Succession Planning

We are committed to board refreshment. Currently, 70% of our directors have a tenure of less than six years. The table below illustrates the tenure of our directors:

We thoughtfully plan for director succession and board refreshment. By developing and following a long-term succession plan, the board has an ongoing opportunity to:

•

evaluate the depth and diversity of experience of our board;

•

anticipate and plan for changes, including retirements;

•

constructively engage with the USW in connection with its nomination rights pursuant to the terms of our Director Designation Agreement (described under "Corporate Governance - Director Designation Agreement);

•

expand and replace key skills and experience that support our strategies;

•

build on our record of board diversity; and

•

maintain a balanced mix of tenures.

The nominating and corporate governance committee also plans for the orderly succession of the executive chair, independent lead director and each of the chairs of our board's five committees, providing for the identification of potential successors, their development and the transition of responsibilities. As a result of the management and execution of our board’s succession plans, a leadership transition of our board’s executive chair position occurred earlier this year when Mr. Harvey became chairman of the board.

Board Composition

Bringing together informed directors with different perspectives and backgrounds, in a well-managed and constructive environment, fosters thoughtful and innovative decision-making. We have a policy of encouraging diversity of gender, ethnicity, age and background, as well as a range of tenures on the board to ensure both continuity and fresh perspectives among our directors. Our directors exhibit a balanced mix of tenures, ages, independence and diversity.

Nominees for Class I Directors

The nominating and corporate governance committee of our board of directors has recommended, and our board of directors has approved, the nomination of the three nominees listed below. The nominees have indicated their willingness to serve as members of the board of directors if elected; however, in case any nominee becomes unavailable for election to the board of directors for any reason not presently known or contemplated, the proxy holders have discretionary authority to vote proxies for a substitute nominee. Proxies cannot be voted for more than three nominees.

The Board of Directors Recommends a Vote "FOR ALL" of the Persons Nominated by the Board of Directors.

Set forth below is information about the Class I director nominees, including their ages, present principal occupations, other business experience, directorships in other public companies in the past five years, membership on committees of our board of directors, and reasons why each individual nominee's specific experience, qualifications, attributes and skills led the nominating and corporate governance committee to recommend, and our board of directors to conclude, that the nominee should serve as a director of the Company.

KIMBERLY T. GLAS

Director since: January 2025

Committee: Audit and Sustainability

Age: 49

DESCRIPTION OF BUSINESS EXPERIENCE:

Ms. Glas has served as President and Chief Executive Officer of the National Council of Textile Organizations, a business organization for American manufacturers in the textile industry, since May 2019, and previously served as Commissioner of the U.S.-China Economic and Security Review Commission, an independent commission of the United States government focusing on national security implications of bilateral trade and the economic relationship with China, from 2019 to 2024. Ms. Glas has extensive experience in government policy development and advocacy and international trade as well as working with labor unions and environmental organizations, including previously serving as Executive Director and President of the BlueGreen Alliance, a strategic national partnership between labor unions and environmental organizations to expand the job-creating potential of the green economy and improve the rights of workers at home and around the world. Ms. Glas holds a Bachelor’s degree in history from the State University of New York at Geneseo.

QUALIFICATIONS:

Ms. Glas has extensive experience in policy development and advocacy, international trade, environmental issues, and working with labor unions and environmental organizations, which allow her to provide guidance and insight to the board and management regarding labor relations, the impact of environmental and regulatory initiatives on US based manufacturers and sustainability. Ms. Glas was designated by the USW as a director candidate pursuant to the terms of our Director Designation Agreement (described under “Corporate Governance - Director Designation Agreement”) in connection with our 2025 Annual Meeting.

KEITH A. HARVEY

President, Chief Executive Officer and Chairman of the Board

Director since: 2020

Committee: Executive (Chair)

Age: 65

DESCRIPTION OF BUSINESS EXPERIENCE:

For information as to Mr. Harvey, see “Executive Officers” below.

QUALIFICATIONS:

Mr. Harvey’s substantial experience with our company and in the aluminum industry allows him to provide his perspective to our board of directors regarding our business, our industry and the strategic direction for our company based on his years of experience with our company in increasing leadership roles and in the aluminum industry.

DONALD J. STEBBINS

Director Since: June 2019

Committees: Compensation (Chair), Executive, and Nominating and Corporate Governance

Age: 67

Other Current Public or Registered Investment Company Board Membership:

– Snap-on Tools (January 2015 - Present)

DESCRIPTION OF BUSINESS EXPERIENCE:

Mr. Stebbins served as President and Chief Executive Officer, and also as a director, of Superior Industries International, Inc. ("Superior"), a manufacturer of aluminum wheels for the automotive industry, from May 2014 to December 2018. For two years prior to joining Superior, Mr. Stebbins provided consulting services to various private equity firms. Mr. Stebbins previously served as Chairman, President and Chief Executive Officer of Visteon Corporation, an automotive components manufacturer, from 2008 until 2012, after having served as Visteon’s President and Chief Operating Officer prior to that time. Before joining Visteon, Mr. Stebbins held various positions with increasing responsibility at Lear Corporation, a supplier of automotive seating and electrical distribution systems, including President and Chief Operating Officer–Europe, Asia and Africa, President and Chief Operating Officer–Americas, and Senior Vice President and Chief Financial Officer. Mr. Stebbins holds a Bachelor of Science degree in finance from Miami University and a Master of Business Administration degree from the University of Michigan.

QUALIFICATIONS:

The board of directors nominated Mr. Stebbins because of his board and chief executive officer experience and, among his other qualifications, his experience and expertise in the automotive industry, international business, manufacturing, sales, product innovation/development, operations, accounting and finance (including as a chief financial officer), mergers and acquisitions, strategy development, executive compensation and leadership development.

Continuing Directors

Set forth below is information about our continuing directors, including their ages, present principal occupations, other business experiences, directorships in other public companies in the past five years, membership on committees of our board of directors, and reasons why each individual director's specific experience, qualifications, attributes or skills led our board of directors to conclude that the director should serve on our board of directors.

Class II Directors – Term Expiring at the 2026 Annual Meeting

LAURALEE E. MARTIN

Director since: September 2010

Committees: Audit (Chair), Compensation, Executive and Sustainability

Age: 74

Other Current Public or Registered Investment Company Board Membership:

– Marcus & Millichap, Inc. (August 2019 - Present)

– Beacon Capital Management (November 2021 - Present)

DESCRIPTION OF BUSINESS EXPERIENCE:

Ms. Martin served as Chief Executive Officer and President of HCP, Inc., a real estate investment trust focusing on properties serving the healthcare industry, from October 2013 to July 2016. Prior to joining HCP, Inc., Ms. Martin served as Chief Executive Officer of the Americas Division of Jones Lang LaSalle, Inc., a financial and professional services firm specializing in real estate services and investment management, from January 2013 to October 2013. She served as Executive Vice President and Chief Financial Officer of Jones Lang LaSalle from January 2002 and was appointed Chief Operating and Financial Officer in October 2005 and served in that capacity until January 2013. She joined Jones Lang LaSalle after 15 years with Heller Financial, Inc., a commercial finance company with international operations, where she was Vice President, Chief Financial Officer, Senior Group President, and President of the Real Estate group. Prior to joining Heller Financial, Ms. Martin held certain senior management positions with General Electric Credit Corporation.

QUALIFICATIONS:

Having served as both the Chief Financial Officer and the head of the real estate lending group at Heller Financial and having served as the Chief Operating and Financial Officer for Jones Lang LaSalle for more than seven and 12 years, respectively, as well as having served as the Chief Executive Officer of the Americas division of Jones Lang LaSalle, Inc. and being the Chief Executive Officer of HCP, Inc., Ms. Martin has significant experience in all aspects of corporate financial and operational matters, including the oversight of complex financial, accounting and corporate infrastructure functions. Her service as a member of the boards of directors of two real estate investment trusts and a major bank holding company have reinforced those qualifications and also have deepened her expertise in corporate governance and matters relating to the Sarbanes-Oxley Act. Ms. Martin also has a deep foundation in evaluating acquisition opportunities, managing banking relationships and investor relations. Ms. Martin's experience and background, qualification as an audit committee financial expert, and understanding of our company's financial statements allow her to provide guidance and insight to our board of directors and management regarding business, strategic, accounting and financial issues.

BRETT E. WILCOX

Director since: July 2006

Committees: Audit, Compensation, Executive and Sustainability (Chair)

Age: 71

DESCRIPTION OF BUSINESS EXPERIENCE:

Mr. Wilcox has served as Chief Executive Officer of Cvictus, a Canadian company developing a single cell protein and related production process to substitute for soybean meal and fishmeal in animal feed, since September 2018 and has been an active investor in, on the board of directors of, or an executive consultant for, a number of metals and energy companies since 2005. From June 2005 to December 2011, Mr. Wilcox served as Chief Executive Officer of Summit Power Alternative Resources where he managed the development of wind generation and new energy technologies. Prior to that, Mr. Wilcox served as: Chief Executive Officer of Golden Northwest Aluminum Company and its predecessors. Mr. Wilcox has also served as Executive Director of Direct Services Industries, Inc., a trade association of large aluminum and other energy-intensive companies; an attorney with Preston, Ellis & Gates in Seattle, Washington; Vice Chairman of the Oregon Progress Board; Chairman of the Oregon Economic and Community Development Commission; a member of the Oregon Governor's Comprehensive Review of the Northwest Regional Power System; and a member of the Oregon Governor's Task Forces on structure and efficiency of state government, employee benefits and compensation, and government performance and accountability.

QUALIFICATIONS:

Mr. Wilcox was selected to serve as a director of our company because of his business and financial background and experience, including his experience as the Chief Executive Officer of Golden Northwest Aluminum Company and its predecessors, his experience working successfully with the USW and his experience in the power industries, and because of his qualification as an audit committee financial expert. Mr. Wilcox was initially designated by the USW as a director candidate in connection with a search process, and, pursuant to the terms of the Director Designation Agreement, was designated by the USW as a director candidate in connection with our 2008, 2011, 2014, 2017, 2020 and 2023 annual meetings of stockholders. Mr. Wilcox's experience as a chief executive officer, his financial expertise, his experience in the aluminum and energy industries, and his working relationship with the USW allow him to offer guidance and insight to our board of directors and management on business, finance, strategic and labor issues.

KEVIN W. WILLIAMS

Director since: September 2021

Committee: Audit and Compensation

Age: 63

DESCRIPTION OF BUSINESS EXPERIENCE:

Mr. Williams has served as President and Chief Executive Officer of GAA Manufacturing and Supply Chain Management, a third-party logistics and supply chain management company and one of the country's largest African American-owned businesses, since August 2018. Mr. Williams previously served as President and Managing Director of General Motors of Canada Limited and Vice President and General Manager, Global Service and Parts Operations of General Motors Company. Mr. Williams also held several other senior global roles at GM including chairman, president and managing director of GM de Mexico, Central America and the Cayman Islands; and global executive director of supplier quality and development for GM Worldwide and GM Europe among other assignments. Mr. Williams holds a Bachelor’s degree in business administration and management from Tennessee State University and a Master of Science degree in business administration and management from Central Michigan University.

QUALIFICATIONS:

The board of directors nominated Mr. Williams to our board because of his extensive manufacturing, automotive and supply chain management expertise as well as experience in labor relations.

Class III Directors – Term Expiring at the 2027 Annual Meeting

MICHAEL C. ARNOLD

Director since: September 2021

Committee: Compensation and Nominating and Corporate Governance (Chair)

Age: 68

Other Current Public or Registered Investment Company Board Membership:

– AGCO Corporation (2013 - Present)

DESCRIPTION OF BUSINESS EXPERIENCE:

Mr. Arnold served as the President and Chief Executive Officer of Ryerson Inc., a processor and distributor of industrial metals, from 2011 to 2015, and has previously held various senior management positions with The Timken Company from 1979 to 2010, including Executive Vice President; President, Bearings and Power Transmission Group; President, Industrial Group; Vice President, Bearings and Business Process Advancement; Director, Bearings and Business Process Advancement; and Director, Manufacturing and Technology, Europe, Africa and West Asia (Europe). Mr. Arnold holds a Bachelor’s degree in mechanical engineering and a Master’s degree in sales and marketing from University of Akron.

QUALIFICATIONS:

The board of directors nominated Mr. Arnold to our board because of his extensive manufacturing and distribution expertise in metals industries and public company board and board leadership experience, as well as his mergers and acquisitions and supply chain experience in metals industries.

DAVID A. FOSTER

Director since: June 2009

Committees: Nominating and Corporate Governance and Sustainability

Age: 77

Other Board Membership:

– Member of board of directors of Evraz North America, d/b/a Oregon Steel Manufacturing (2006 - Present)

DESCRIPTION OF BUSINESS EXPERIENCE:

Since May 2017, Mr. Foster has served as Distinguished Associate of Energy Futures Initiative, a non-profit organization conducting objective, fact-based and rigorous technical, economic, financial and policy analyses supported by a multidisciplinary network of experts. Mr. Foster has also served as a visiting scholar at the Massachusetts Institute of Technology since May 2019, working on the Roosevelt Project, a multi-year research project focused on energy technology and economic development.

Mr. Foster was Senior Advisor to the Office of the Secretary of the U.S. Department of Energy from June 2014 to January 2017. Prior to that, Mr. Foster was Executive Director of the BlueGreen Alliance, a strategic national partnership between labor unions and environmental organizations to expand the job-creating potential of the green economy and improve the rights of workers at home and around the world, from June 2006 to June 2014 and an adjunct faculty member of the University of Minnesota from January 2003 to June 2014. Mr. Foster was also previously a director of the USW for District #11.

QUALIFICATIONS:

The board of directors nominated Mr. Foster because of his extensive labor experience representing the USW; experience with the BlueGreen Alliance which allows him to provide guidance and insight to the board and management regarding labor relations, including with the USW, relations with our hourly workforce, the impact of environmental and regulatory initiatives on US based manufacturers and sustainability; and experience with the Energy Future Initiatives and projects focused on energy technology. Mr. Foster was designated by the USW as a director candidate pursuant to the terms of our Director Designation Agreement in connection with our 2009, 2012, 2015, 2018, 2021 and 2024 annual meetings of stockholders. However, his experience with our company exceeds 20 years and includes his former role as the primary USW negotiator of our master labor agreement with the USW prior to joining our board of directors.

RICHARD P. GRIMLEY

Director since: April 2023

Committees: Compensation and Sustainability

Age: 66

DESCRIPTION OF BUSINESS EXPERIENCE:

Mr. Grimley has served as a consultant since June 2021 and previously served as Senior Vice President of Global Operations of Ball Corporation, a global aluminum manufacturing company, from July 2016 to June 2021. Prior to joining Ball Corporation, Mr. Grimley held various senior management positions with Rexam and its subsidiaries, including Global Director of Operations of Rexam Group, President and Chief Executive Officer of North America of Rexam, Chief Operating Officer of North and South Americas of Rexam Beverage Cans, and Vice President of Manufacturing of Rexam. Mr. Grimley holds a Bachelor’s degree in business administration from the University of Iowa and a Master’s degree in business administration from Benedictine University.

QUALIFICATIONS:

The board of directors nominated Mr. Grimley as a director because of his extensive experience in the aluminum packaging industry and manufacturing operations. Mr. Grimley was designated by the USW as a director candidate pursuant to the terms of our Director Designation Agreement in 2023 and in connection with the 2024 annual meeting of stockholders.