Proxy Statement (Form DEF 14A)

2026 Proxy Statement and

Notice of Annual Meeting of Stockholders

STEPAN COMPANY

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To be held on April 28, 2026

at 9:00 a.m. (CDT)

To the Stockholders:

Notice is hereby given that the 2026 Annual Meeting of Stockholders (the "Annual Meeting") of Stepan Company (the "Company") will be held at the Company's offices at 1101 Skokie Boulevard, Northbrook, Illinois 60062, on Tuesday, April 28, 2026, at 9:00 a.m. (CDT), for the following purposes:

The Board of Directors has designated the close of business on March 2, 2026, as the record date for determining the holders of record of the Company's Common Stock entitled to notice of and to vote at the meeting.

The Board of Directors extends a cordial invitation to all stockholders to attend the Annual Meeting. Whether or not you plan to attend the meeting, please mark, sign and mail the enclosed proxy card in the return envelope provided or vote by internet or phone as promptly as possible.

As a reminder, your broker may not vote your shares for non-routinematters such as the election of directors or the Say-on-Payvote without your specific instructions as to how to vote. Therefore, we urge you to provide your broker with voting instructions by returning your proxy card so your votes for all proposals can be counted.

Directions to the Annual Meeting are available at https://stepan.gcs-web.com/annual-meetingfor those stockholders who plan to attend the Annual Meeting.

By order of the Board of Directors,

Shawn G. Lisle

Vice President, General Counsel and Secretary

Northbrook, Illinois

March 25, 2026

Important Notice Regarding the Availability of Proxy Materials for the

Annual Meeting of Stockholders to Be Held on April 28, 2026

The Company's Proxy Statement, 2025 Annual Report to Stockholders and Annual Report on Form 10-Kfor the year ended December 31, 2025, are available at http://www.edocumentview.com/SCL.

TABLE OF CONTENTS

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March 25, 2026

PROXY STATEMENT

For the Annual Meeting of Stockholders of

STEPAN COMPANY

1101 Skokie Boulevard

Northbrook, Illinois 60062

To be held at 9:00 a.m. (CDT) on April 28, 2026

INFORMATION CONCERNING SOLICITATION AND VOTING

The enclosed proxy is solicited by the Board of Directors, and the Company will bear the entire expense of solicitation. Such solicitation is being made by mail, and the Company's officers and employees may solicit proxies from stockholders personally or by telephone, mail or other means. The Company will make arrangements with the brokers, custodians, nominees and other fiduciaries who request the forwarding of solicitation material to the beneficial owners of shares of the Company's stock held of record by such brokers, custodians, nominees and other fiduciaries, and the Company will reimburse them for their reasonable out-of-pocketexpenses. This proxy statement and proxy are first being distributed to stockholders commencing on or about March 25, 2026.

At the close of business on March 2, 2026, the record date for the meeting, there were 22,690,379 shares of the Company's Common Stock ("Common Stock") outstanding, each share of which is entitled to one vote on each matter to be voted on at the meeting. The required quorum at the Annual Meeting is a majority of the outstanding shares of the Company's Common Stock as of the record date.

If you submit your proxy but abstain from voting on one or more matters, your shares will be counted as present at the meeting for the purposes of determining a quorum. You may revoke your proxy by attending the meeting and voting in person or by delivering to the Secretary of the Company a revocation of the proxy or an executed new proxy bearing a later date.

You may vote "FOR," "AGAINST" or "ABSTAIN" on each of the nominees for the Board of Directors. You may vote "FOR," "AGAINST" or "ABSTAIN" on each of the other proposals. If you vote to "ABSTAIN" with respect to a nominee for the Board of Directors, your abstention will not be included in the vote totals and will not affect the outcome of the vote. If you vote to "ABSTAIN" with respect to any other proposal, your abstention will have the effect of a vote against the proposal.

For any other business that may properly come before the meeting, votes will be cast pursuant to the authority granted by the enclosed proxy in accordance with the best judgment of the individuals acting under the proxy. The Board of Directors is not currently aware of any other business that may come before the meeting.

If you hold your shares in street name and do not provide voting instructions to your broker, custodian, nominee or other fiduciary, your shares will not be voted on any non-routinematters and will be considered "broker non-votes." Non-routinematters include the election of directors, and the Say-on-Payvote. Your broker may vote your shares without instruction on the ratification of the appointment of the Company's independent registered public accounting firm. Broker non-voteswill be counted as present at the meeting for the purpose of determining a quorum but will not be included in the vote totals for non-routinematters and will not affect the outcome of those votes. Please instruct your broker or bank so your vote can be counted on all proposals.

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In order to ensure the necessary quorum at the Annual Meeting, please mark, sign and return the enclosed proxy promptly in the envelope provided. You may also vote via the internet by visiting http://www.envisionreports.com/SCL or by phone by calling (800) 652-8683.Internet and phone voting will be available 24 hours a day, seven days a week until 1:00 a.m. (EDT) on April 28, 2026. If voting via the internet or by phone, please have your proxy card available and follow the instructions to vote. Even if you vote prior to the meeting, you are invited to attend the meeting.

In the future, in accordance with the rules of the Securities and Exchange Commission (the "SEC"), the Company may furnish proxy materials, including its proxy statements and annual reports, to stockholders by providing access to these documents on the internet instead of mailing printed copies. If the Company elects to take this approach, most stockholders would not receive printed copies of the proxy materials. Instead, the notice would provide instructions on how to access and review the proxy materials on the internet. The notice would also provide instructions on how to submit your proxy via the internet. For stockholders who prefer to receive printed copies of the proxy materials, the notice would provide instructions for requesting printed copies.

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PROPOSAL NO. 1: ELECTION OF DIRECTORS

Stockholders and the persons named in the enclosed proxy will vote, pursuant to the authority granted by the stockholder in the enclosed proxy, on the election of Mr. Joaquin Delgado, Mr. Corning F. Painter and Mr. F. Quinn Stepan, Jr. as directors of the Company, to hold office until the Annual Meeting of Stockholders to be held in 2029. The Board of Directors is divided into three classes serving staggered three-year terms. Directors for each class are elected at the annual meeting of stockholders in the year in which the term for their class expires. Mr. Delgado, Mr. Painter, and Mr. Stepan are current directors whose terms expire in 2026. Each of Mr. Delgado and Mr. Stepan were last elected by the Company's stockholders at the 2023 Annual Meeting. Mr. Painter was elected by the Board of Directors on June 9, 2025. The nominations of Mr. Delgado, Mr. Painter, and Mr. Stepan have each been reviewed and recommended by the Nominating and Corporate Governance Committee and the Board of Directors.

In the event any of Mr. Delgado, Mr. Painter or Mr. Stepan is unable to serve as director, votes will be cast, pursuant to the authority granted in the proxy, for such person or persons as may be designated by the Board of Directors. The Board of Directors at this time is not aware of any nominee who is or will be unable to serve as director, if elected.

Under the Company's Amended and Restated By-laws,in an uncontested election directors are elected by a majority of the votes cast by stockholders. An uncontested election of directors means an election for which the number of nominees does not exceed the number of directors to be elected at the specific election. Because three directors are to be elected, and Mr. Delgado, Mr. Painter and Mr. Stepan are the sole nominees, this election is uncontested, and therefore the nominees must receive a majority of votes cast by stockholders to be elected.

Nominees for Director

The following table sets forth certain information about the nominees for director:

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PROPOSAL: The Board of Directors recommends that the stockholders vote FOR the election of Mr. Delgado, Mr. Painter, and Mr. Stepan to the Board of Directors, each for a three-year term.

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Directors Who Are Not Nominated for Election

The following table sets forth certain information about those directors who are not up for election:

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SECURITY OWNERSHIP

Security Ownership of Certain Beneficial Owners

As of March 2, 2026, the following persons were the only persons known to the Company to beneficially own more than five percent of the Company's Common Stock, other than members of the Company's Board of Directors or management, whose ownership is set forth in the table below:

Security Ownership of the Board of Directors and Management

The following table sets forth, as of March 2, 2026, the security ownership of each executive officer listed in the Summary Compensation Table in this proxy statement, each director and nominee for director, and all currently serving directors and executive officers as a group. The address for each director, nominee for director, and executive officer is c/o Stepan Company, 1101 Skokie Boulevard, Northbrook, Illinois 60062.

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Delinquent Section 16(a) Reports

Section 16(a) of the Securities Exchange Act of 1934 (the "Exchange Act") and the rules thereunder require the Company's executive officers, directors, and persons who own more than ten percent of the Common Stock, to file reports of beneficial ownership and changes in beneficial ownership of Common Stock with the SEC. Based solely upon a review of such reports filed with the SEC and written representations from certain reporting persons, the Company believes that all such required reports have been timely filed, other than reports by Mr. Delgado reporting an equity grant, which form was inadvertently filed late due to administrative error.

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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

Policies and Procedures for Approving Related Person Transactions

The Company has adopted a written policy entitled "Related Party Transaction Policy" (the "Related Party Transaction Policy"). The policy was initially approved by the Audit Committee of the Board of Directors in February 2007, has been annually reviewed by the Audit Committee and was last amended in April 2024. This policy applies to material transactions ("Related Party Transactions") involving the Company and a Related Party, which is defined as a person or entity who is a Company executive officer, director, nominee for election as a director, beneficial owner of five percent or more of the Company's Common Stock, or immediate family member of these persons, or any entity for which any of the foregoing persons is an executive officer, general partner, managing member, principal or greater than five percent beneficial owner. The Related Party Transaction Policy states that the Company will consummate a Related Party Transaction only when the Audit Committee approves the transaction after considering the factors set forth in the Related Party Transaction Policy. If advance Audit Committee approval of a Related Party Transaction is not feasible, then the Company may preliminarily enter into the transaction upon prior approval by the Chair of the Audit Committee, subject to ratification of the transaction by the Audit Committee at its next regularly scheduled meeting. No director may participate in the approval of a Related Party Transaction for which he or she is a Related Party.

The factors considered by the Audit Committee in its evaluation of a Related Party Transaction include the relevant facts and circumstances of the proposed Related Party Transaction, whether the Related Party Transaction is on terms comparable to those that could be obtained in arm's-lengthdealings with an unrelated third party, the extent of the related party's interest in the transaction and the conflicts of interest and corporate opportunity provisions of the Company's Code of Conduct.

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CORPORATE GOVERNANCE PRINCIPLES AND BOARD MATTERS

Corporate Governance Guidelines and Code of Conduct

The Company is committed to having sound corporate governance principles and has adopted Corporate Governance Guidelines and a Code of Conduct to maintain those principles. The Company's Code of Conduct applies to all of the Company's directors, officers and employees, including the Company's Chief Executive Officer and Chief Financial Officer. The Company's Corporate Governance Guidelines and Code of Conduct are available at https://stepan.gcs-web.com/corporate-governance/highlights.Stockholders may also request free printed copies of the Company's Corporate Governance Guidelines and Code of Conduct by contacting the Company's Secretary at Stepan Company, Secretary's Office, 1101 Skokie Boulevard, Northbrook, Illinois 60062.

Board Committees

The Board of Directors has four standing committees: the Audit Committee, the Compliance Committee, the Human Capital and Compensation Committee, and the Nominating and Corporate Governance Committee, each composed entirely of independent directors. The charter of each committee is available at https://stepan.gcs-web.com/corporate-governance/highlights.

Audit Committee

The primary functions of the Audit Committee are to (a) assist the Board of Directors in fulfilling its oversight responsibilities to stockholders, the investment community and creditors in relation to (i) the quality and integrity of the Company's financial statements, (ii) the adequacy of the Company's internal control over financial reporting, (iii) the Company's compliance with legal and regulatory requirements (in coordination with the Compliance Committee), (iv) the registered public accounting firm's qualifications and independence, and (v) the performance of the independent auditors and the Company's internal audit function; and (b) prepare the Audit Committee report included in each proxy statement. The responsibilities of the Audit Committee include annual selection and engagement of the Company's independent registered public accounting firm, review of the proposed fees and scope of work of the independent registered public accounting firm's year-endaudit, review with the Company's independent registered public accounting firm of the results of the year-endaudits of the Company's financial statements and internal control over financial reporting, review of the Company's financial statements with the Company's independent registered public accounting firm prior to the Company's filing of each quarterly report on Form 10-Qand annual report on Form 10-K,review of findings reported by the Company's internal audit department and management's responses, review of the internal audit program of the Company and review, approval or disapproval of Related Party Transactions pursuant to the Company's Related Party Transaction Policy and review of the Company's risk assessment and risk management policies and procedures, including those relating to the Company's enterprise risks, financial risks and information security risks. The Audit Committee held four meetings in 2025.

The Audit Committee is comprised of Ms. Burgess (Chair), Mr. Dearth, Mr. Delgado, Ms. Lewis, Mr. Painter and Ms. Reed all of whom are financially literate and are independent directors in accordance with the rules of the New York Stock Exchange (the "NYSE") and the SEC and as described below under "Director Independence." The Board of Directors has determined that Ms. Burgess qualifies as an audit committee financial expert within the meaning of SEC regulations.

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Compliance Committee

The primary functions of the Compliance Committee are to assist the Board in fulfilling its oversight responsibilities with respect to (a) the Company's overall compliance with significant legal and regulatory requirements, as well as (b) compliance with its business ethics policies and Code of Conduct. The Compliance Committee held four meetings in 2025.

The Compliance Committee is comprised of Ms. Burgess, Mr. Dearth (Chair), Mr. Delgado, Ms. Lewis, Mr. Painter, and Ms. Reed, all of whom are independent directors in accordance with the rules of NYSE and as described below under "Director Independence."

Human Capital and Compensation Committee

The primary functions of the Human Capital and Compensation Committee are to (a) establish and administer the Company's policies, programs and procedures for compensating its executive management and (b) provide advice and counsel to the Company regarding executive development and succession planning. The responsibilities of the Human Capital and Compensation Committee include reviewing and setting or recommending the compensation of the Company's executive officers, recommending and administering cash-based and equity-based incentive compensation plans, reviewing and recommending director compensation, reviewing and recommending the Company's Compensation Discussion and Analysis included in each proxy statement, and preparing the Human Capital and Compensation Committee Report included in each proxy statement. The Human Capital and Compensation Committee also reviews and advises management regarding the Company's human capital management. The Human Capital and Compensation Committee held four meetings in 2025.

The Human Capital and Compensation Committee is comprised of Ms. Burgess, Mr. Dearth, Mr. Delgado, Ms. Lewis, Mr. Painter, and Ms. Reed (Chair), all of whom are independent directors in accordance with the rules of NYSE and the SEC and as described below under "Director Independence."

Nominating and Corporate Governance Committee

The primary functions of the Nominating and Corporate Governance Committee are to (a) identify individuals qualified to become board members and recommend the director nominees for election at each annual meeting of stockholders, (b) develop and recommend the Company's Corporate Governance Guidelines, (c) oversee the evaluation of the Board of Directors and (d) recommend the members for each Board committee. In addition, the responsibilities of the Nominating and Corporate Governance Committee include making recommendations to the Board on corporate governance matters and the Board's structure. The Nominating and Corporate Governance Committee held three meetings in 2025.

The Nominating and Corporate Governance Committee is comprised of Ms. Burgess, Mr. Dearth, Mr. Delgado (Chair), Ms. Lewis, Mr. Painter, and Ms. Reed, all of whom are independent directors in accordance with the rules of NYSE and as described below under "Director Independence."

Board Performance Evaluations

Annually, each director completes an evaluation of the full Board of Directors and of each standing committee on which the director serves. The Company's Vice President, General Counsel and Secretary compiles the results of the assessments and provides the results to the Nominating and Governance Committee and to the Board of Directors. The Board of Directors initially discusses the

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assessment results with the Chairman and the Chief Executive Officer in attendance, and if desired by any director, the assessment results are also discussed at Executive Sessions of the non-managementdirectors and at Executive Sessions of the independent directors. This assessment evaluates the Board of Directors' composition and contribution as a whole to the Company and reviews areas in which the Board of Directors and/or management believes a stronger contribution could be made. The Nominating and Corporate Governance Committee is also responsible for evaluating the performance of current members of the Board of Directors at the time they are considered for re-nominationto the Board of Directors.

Board Meetings and Attendance

During 2025, the Board of Directors held five meetings. During 2025, all of the directors attended more than 75% of the total number of meetings of the Board of Directors and the meetings of committees of the Board of Directors of which each director was a member. While all directors are encouraged to attend, the Company does not have a formal policy requiring attendance at the Company's annual meeting of stockholders. Except for the since retired Mr. Wehmer, who attended virtually, all directors attended the 2025 Annual Meeting of Stockholders in person. The Company currently expects that all directors and nominees will attend the 2026 Annual Meeting.

Director Nomination Process

The Corporate Governance Guidelines contain the Board of Directors membership criteria that apply to nominees recommended by the Nominating and Corporate Governance Committee for a position on the Board of Directors. Under these criteria, members of the Board of Directors should possess qualities that include strength of character, an inquiring and independent mind, practical wisdom and mature judgment. In addition to these qualities, director nominees should also possess recognized achievement, an ability to contribute to some aspect of the Company's business, and the willingness to make the commitment of time and effort required of a director. The Nominating and Corporate Governance Committee's process for identifying and evaluating director nominees includes recommendations by stockholders, search firms, non-managementdirectors and executive officers, a review and background check of specific candidates, an assessment of the candidate's independence under the director independence standards described below, and interviews of director candidates by the Nominating and Corporate Governance Committee.

It is the policy of the Nominating and Corporate Governance Committee to consider candidates recommended by stockholders for membership on the Board of Directors. The Nominating and Corporate Governance Committee's evaluation of a nominee recommended by a stockholder would consider the general criteria and required information previously described in this section, and any other factors the Nominating and Corporate Governance Committee deems relevant. Any stockholder recommendation proposed for consideration by the Nominating and Corporate Governance Committee must comply with the requirements set forth in the Company's By-laws.Among other things, a stockholder must give written notice containing the information required by the Company's By-lawsto the Secretary of the Company at Stepan Company, Secretary's Office, 1101 Skokie Boulevard, Northbrook, Illinois 60062. The deadline to submit a director recommendation for the 2027 Annual Meeting of Stockholders is set forth in the "2027 Stockholder Proposals and Director Nominations" section below.

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Board Composition

The following charts summarize the current composition of the Board of Directors:

In accordance with the Company's Corporate Governance Guidelines, when identifying director nominees, the Nominating and Corporate Governance Committee and the Board of Directors consider candidates who have strength of character, an inquiring and independent mind, practical wisdom, and the ability to make mature business judgments with integrity. In addition to these qualities, the Nominating and Corporate Governance Committee and the Board of Directors also considers a diversity of professional, technical, operational, international and financial experience, qualifications, and skills that, taken together as a whole, provide the Board with the necessary tools to perform its oversight function effectively in light of the Company's business, industry and structure.

Director Independence

For purposes of determining director independence, the Company uses the NYSE director independence standards. No director qualifies as "independent" unless the Board of Directors affirmatively determines that the director has no material relationship with the Company (either directly or as a partner, shareholder or officer of an organization that has a relationship with the Company). In addition, a director is not independent if:

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Under the NYSE rules and the Company's Corporate Governance Guidelines, at least a majority of the Company's directors and each member of the Audit Committee, Compliance Committee, Human Capital and Compensation Committee and Nominating and Corporate Governance Committee must meet the independence standards set forth above. The Board of Directors has determined, following the recommendation of the Nominating and Corporate Governance Committee, that each of Ms. Burgess, Mr. Dearth, Mr. Delgado, Ms. Lewis, Mr. Painter and Ms. Reed is independent under the standards set forth above. Additionally, the Board of Directors determined that Mr. Wehmer was independent prior to his retirement. In addition, the Board of Directors has determined that each of the members of the standing committees satisfies the Company's independence standards, including the additional independence standards and financial literacy requirements required for audit committee members and compensation committee members, as applicable, established by SEC and NYSE rules. Mr. F. Quinn Stepan, Jr. is not deemed independent under the NYSE rules because his brother, Richard Stepan, serves as an executive officer of the Company. Mr. Rojo is not deemed independent under the NYSE rules because he currently serves as the President and Chief Executive Officer of the Company.

In making independence determinations, the Nominating and Corporate Governance Committee, with assistance from the Company's legal counsel, evaluated responses to a questionnaire completed annually by each director regarding relationships and possible conflicts of interest between each director, the Company and management. In its review of director independence, the Nominating and Corporate Governance Committee considered the commercial, industrial, banking, consulting, legal, accounting, charitable, and familial relationships any director may have with the Company or management. In addition, the Nominating and Corporate Governance Committee considered any relationships between the Company and entities for which any director serves as management or a member of the board of directors.

Board Leadership Structure

The Board of Directors regularly reviews its leadership structure in light of the Company's then-current needs, trends, internal assessments of Board effectiveness, and other factors. The Board does not have a policy regarding the separation of the roles of Chief Executive Officer and Chairman of the Board because the Board believes it is in the best interests of the Company to make that determination based on the position and direction of the Company and the membership of the Board.

Currently, the Board believes the interests of the Company and its stockholders are best served through a leadership model with the roles of Chairman and Chief Executive Officer separated. Mr. Stepan, who served as the Company's Chief Executive Officer until April 25, 2022, continues to serve as Chairman of the Board. Mr. Rojo is Chief Executive Officer and is a member of the Board.

The Board believes that Mr. Stepan's experience puts him in the best position to provide broad leadership for the Board in the role of Chairman as the Board works to deliver value to stockholders. Mr. Stepan possesses extensive knowledge and understanding of the Company and its operations, strategic planning matters, and the industry in general, developed during his over 30-yearcareer with the Company.

To aid the Board's independent oversight of the Company and management, the Board has elected Mr. Dearth as Lead Independent Director. The Board believes that the election of the Lead Independent Director enhances the Board's commitment to maintaining strong corporate governance

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and provides effective independent Board leadership. Among other responsibilities, the Lead Independent Director presides at all Executive Sessions of the independent directors, advises the Chairman on Board meeting schedules, agendas and materials, and serves as principal liaison between the independent directors and the Chairman. The Lead Independent Director also provides input to the evaluation of the Chief Executive Officer, which process is led by the chair of the Human Capital and Compensation Committee and the Chairman of the Board.

In addition, the independent directors regularly meet in Executive Sessions without the Chairman, the Chief Executive Officer and other members of management present in accordance with the Company's Corporate Governance Guidelines.

Risk Management

The Board of Directors takes an active role in overseeing the Company's financial and non-financialrisks. The Audit Committee, which is chaired by Ms. Burgess, leads the Board's oversight of Company risks. The Audit Committee reviews the Company's risk assessment and risk management policies and procedures, including those relating to the Company's enterprise risks, financial risks and information security risks. The Audit Committee receives reports from the Company's Director of Internal Audit, Chief Compliance and Risk Officer, Chief Financial Officer, and General Counsel, all of whom are responsible for various aspects of the Company's risk management. The Director of Internal Audit reports directly to the Audit Committee. The Audit Committee also meets with the Company's external auditors separately from management.

The Compliance Committee, which is chaired by Mr. Dearth, oversees risk assessment and risk mitigation related to matters within the Compliance Committee's oversight responsibilities, which may include environmental protection, employee health, safety and security, data privacy, employment, anti-bribery and anti-corruption, product quality compliance, and ethics and compliance training.

The Human Capital and Compensation Committee, which is chaired by Ms. Reed, takes the lead role in overseeing the management of risks as they relate to the Company's compensation policies and practices. During 2025, the Human Capital and Compensation Committee reviewed these compensation policies and practices and did not identify any risks that are reasonably likely to have a material adverse effect on the Company.

Executive Sessions

The Company's Corporate Governance Guidelines require Executive Sessions of independent directors to be held at least once per year. Any independent director can request that additional Executive Sessions be scheduled. In 2025, five Executive Sessions without management were held by the independent directors and chaired by Mr. Wehmer and then Mr. Dearth in their respective capacities as Lead Independent Director. In addition, Executive Sessions without management were also held after many Board committee meetings during 2025 and were chaired by the respective chairs of the Board committees.

Compensation Committee Interlocks and Insider Participation

The members of the Company's Human Capital and Compensation Committee in 2025 were Ms. Burgess, Mr. Dearth, Mr. Delgado, Ms. Lewis, Mr. Painter, and Ms. Reed (Chair). None of the members of the Human Capital and Compensation Committee during 2025 were at any time an officer or employee of the Company nor did any member participate in a Related Party Transaction. In 2025, none of the Company's executive officers served as a member of the compensation committee of another entity, or as a director of another entity, one of whose executive officers served on the Human Capital and Compensation Committee or as one of the Company's directors.

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EXECUTIVE COMPENSATION

Compensation Discussion and Analysis

Summary of Executive Compensation in 2025

In 2025, the Company and the Human Capital and Compensation Committee of the Board of Directors (the "Committee") applied the compensation policies and principles described in this Compensation Discussion and Analysis in determining the compensation for the individuals named in the Summary Compensation Table. Those individuals are referred to herein as the named executive officers ("NEOs"). The NEOs for 2025 were:

Significant Developments in 2025

Company Performance

Key Developments Impacting Executive Compensation

¹ Adjusted net income is a financial measure that has not been calculated pursuant to U.S. generally accepted accounting principles ("GAAP"). See Appendix A for further discussion and a reconciliation of this non-GAAPfinancial measure to net income, the most directly comparable GAAP financial measure.

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2025 Key Executive Transitions

Effective July 15, 2025, Mr. Velasquez joined the Company as its Vice President and Chief Financial Officer.

Mr. Hinrichsen served as Vice President and Interim Chief Financial Officer from October 30, 2024 to July 14, 2025, and Global Vice President, Finance and Investor Relations until October 31, 2025.

Executive Compensation Best Practices the Company Follows

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Compensation Philosophy

The basic premise of the Company's executive compensation philosophy is to pay for performance. The Company's intention is to foster a performance-driven culturewith competitive total compensation as a key driver for all employees. Compensation levels commensurate with Company performance are designed to align the interests of our employees with the interests of our stockholders. To better align our NEOs' compensation with the interests of our stockholders, a substantial portion of compensation is at-riskand performance-based.

The Company's guiding philosophy in setting executive compensation is that the compensation of executive officers should reflect the scope of their job responsibilitiesand the level of individual and corporate performance achieved. Executive compensation should be competitive internally and externally with like or comparable positions based on job descriptions and responsibilities at similarly sized companies within the Company's industry, Peer Group (as defined below) and other appropriate related industry data or survey information. The Company's compensation philosophy is reviewed at least annually by the Committee.

The effectiveness of the executive compensation program is primarily measured by Company performance, stock price appreciation, the ability of the Company to attract and retain executive officers, and comparison against other relevant, external benchmarks as needed.

The Committee generally does not consider the impact of previously awarded compensation in determining current executive total compensation. The Committee does, however, use both a chemical industry peer group as well as aggregate executive compensation survey data to annually assess executive compensation as described below under "Compensation Peer Group and Survey Data." Except for the limits regarding incentive compensation as described below, the Committee does not use specific policies to allocate between cash and non-cashcompensation or between short-term and long-term compensation.

Compensation Objectives

The overall objectives of the Company's compensation program (in which each NEO participates) are as follows:

Role of the Human Capital and Compensation Committee

The Committee is responsible for overseeing the establishment and administration of the Company's policies, programs and procedures for compensating the Company's executive management, as further described below. The Committee is also responsible for providing advice to the Company regarding executive development and succession planning. The Committee may, in its discretion, delegate all or a portion of its duties and responsibilities to a subcommittee or, to the extent permitted by applicable law, to any other body or individual.

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Role of the Compensation Consultant

The Committee engaged Exequity LLP ("Exequity") as its independent compensation consultant for 2025. Exequity advises the Committee on a range of executive compensation matters. The scope of Exequity's services to the Committee includes, but is not limited to, the following:

Exequity reports directly to the Committee. The Committee conducted its annual assessment of Exequity's independence pursuant to SEC rules and determined that no conflict of interest exists that would prevent Exequity from independently advising the Committee. Exequity does not provide any other services to management or the Company.

Role of the Committee and Executives in Establishing Executive Compensation

The Committee determines the compensation of the Chief Executive Officer. The Chief Executive Officer and Vice President and Chief Human Resources Officer make recommendations to the Committee regarding compensation for all other executive officers, including the NEOs, other than with respect to their own compensation. The Committee then reviews these recommendations and approves the final compensation for all executive officers. All recommendations made to the Committee and all determinations made by the Committee are based upon the Company's policies and guidelines and other relevant factors outlined in the "Compensation Peer Group and Survey Data" and "Elements of Compensation" sections below.

Advisory Vote to Approve Executive Compensation

The advisory vote in 2025 was the fifteenth consecutive year that the Company's Say-on-Payvote was supported by its stockholders with the approval of more than 96% of shares present and entitled to vote (counting abstentions as votes against) at the annual meeting of stockholders. As stated above, the Company's advisory Say-on-Payvote was supported by 96% of shares present and entitled to vote at the Company's 2025 Annual Meeting. The Committee acknowledges and values the feedback from the Company's stockholders on the annual Say-on-Payvote and believes that these results demonstrate stockholder support of the Company's executive compensation programs. As a result of the strong stockholder support for the 2025 Say-on-Payvote, the Committee determined that the

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Company's compensation practices and processes did not require any significant modifications to achieve the desired results of the Company's compensation program or to address stockholder concerns and therefore did not make any changes as a direct result of such vote results. The Committee will continue to consider the outcome of these advisory votes when determining future executive compensation arrangements.

Executive Pay Mix

The Company targets a total compensation mix where fixed pay, consisting of base salary, is less than half of the total compensation that any NEO or executive officer may earn in any given year. The combined mix of both short-term and long-term incentives for executive officer compensation is structured to encourage the necessary focus and motivation to achieve outstanding results on an ongoing basis, both in the short term and long term. In addition, the combined focus on both short-term and long-term objectives is designed to align executive officers' and stockholders' interests. Short-term incentives for executive officers are based on individual and Company performance. Long-term incentives for executive officers are based on Company performance (performance shares) or are time-vested (RSUs and SARs). The Company's total compensation targets assume above-average Company performance, and potential compensation can vary considerably depending on overall Company performance. The graphics below illustrate the pay mix for our Chief Executive Officer and other NEOs on an average basis using target level of performance for all incentive awards.

Compensation Peer Group and Survey Data

To better understand the compensation practices of similar companies, the Committee reviews data gathered from a custom peer group ("Peer Group") and general market survey data from Mercer LLC ("Mercer"). Information gathered from the Peer Group serves as the primary reference point for the Committee, with Mercer survey data used as a secondary reference.

The Peer Group consists of companies selected on the basis of chemical industry affiliation and size as compared to the Company (e.g., total revenues and market capitalization). The following companies comprised the Peer Group that the Committee referenced when setting 2025 compensation:

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The Committee undertakes annual evaluations of the Peer Group in order to ensure the Company is comparing itself with companies that have the characteristics to appropriately match the Company. Exequity performed a review of the Peer Group listed above in July 2024, and the Committee did not make changes to the Peer Group as a result of such review. The Committee and its independent compensation consultant will continue to monitor the Peer Group going forward as appropriate.

When assessing the competitiveness of Company compensation programs, the Committee, in part, uses median compensation levels in the Peer Group as a reference point to provide a framework for and on which to base individual compensation decisions. The Committee generally references median total compensation for executive officers, but the Committee retains discretion to determine appropriate compensation levels. The Committee believes that all NEOs' and executive officers' total compensation amounts are within appropriate and reasonable levels as compared to the Peer Group data considering performance, experience level, time in position and both external and internal equity evaluations.

Elements of Compensation

For the fiscal year ended December 31, 2025, the principal elements of compensation for the executive officers, including the NEOs, were as follows:

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Base Salary

The Company has established salary grades and ranges for all global employees, including the NEOs. Salary grades reflect the responsibility level of the position (i.e., positions with a greater level of responsibility have a higher salary grade). The salary range for each grade is primarily based on survey data. The salary grade structure enables the Company to ensure that pay is both market competitive and internally equitable.

The Committee, taking into consideration the performance of the Company, the Company's compensation philosophy, the Peer Group data, and the executive's performance, reviews and determines the Chief Executive Officer's salary on an annual basis. The Chief Executive Officer and the Vice President and Chief Human Resources Officer make recommendations to the Committee regarding compensation for all other NEOs. The Committee has the discretion to approve such recommendations or revise the recommended amounts, higher or lower, based upon each executive officer's individual performance. The Chief Executive Officer's salary range is determined based on the same factors and criteria as those for the other NEOs and executive officers.

The NEOs' base salaries for 2025, as of December 31, 2025, are shown below (as well as a comparison against the salaries in effect on December 31, 2024 for each NEO, as applicable).

Short-Term Incentive Compensation

NEOs and certain other employees are eligible for short-term incentive compensation as set forth in the Management Incentive Plan. The purpose of the Company's short-term incentive compensation program is to promote improvement in year-over-year financial performance; to motivate, attract and retain executive, managerial and key employees of outstanding ability; and to align participants' interests directly with the Company's financial targets. The target amount of short-term incentive compensation for each NEO is expressed as a percentage of the executive's actual base salary earned during the respective calendar year. Because senior managers have a greater ability to impact Company results, a significant percentage of their total target compensation is at-risk.The Chief Executive Officer position has the highest level of responsibility, and therefore, the target percentage exceeds the other NEOs' target percentages.

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The extent, if any, to which an incentive award will be payable to an NEO will be based primarily upon the degree of achievement of pre-establishedperformance goals over the specified calendar year. In years when Company performance is exceptional and above the Target level, it is possible for NEOs to receive annual incentive payments above Target, while in years when Company or individual performance is below the Threshold level for a particular metric, no annual incentive will be paid based upon performance on that metric. In addition, the Committee may, in its sole discretion, increase, reduce or eliminate the amount that would otherwise be payable to the NEO with respect to a calendar year.

The following chart reflects the Target Annual Incentive Award and Maximum Annual Incentive Award for each NEO for 2025 under the terms of the Management Incentive Plan (which target amounts were not increased from the targets in effect at the end of 2024 for any NEO):

Each NEO's annual incentive payment is determined based on the Company's achievement of overall performance objectives ("Corporate Performance Objectives") and the achievement of individual performance objectives ("Individual Performance Objectives"), as described below. For 2025, a multiplier is applied to increase each NEO's Annual Incentive Award if Corporate Net Income (as defined below) met or exceeded the Target objective.

Corporate Performance Objectives

The Committee establishes the Corporate Performance Objectives at the beginning of each calendar year. For 2025, the Committee established targets for the four Corporate Performance Objectives for all NEOs: Corporate Net Income, Corporate EBITDA, Corporate Free Cash Flow, and Corporate Safety.² The Committee added Corporate Free Cash Flow and Corporate Safety to the Corporate Performance Objectives in 2025 in order to better align with market practice.

For 2025, the following performance levels were established for the Corporate Net Income objective:

For 2025, the following performance levels were established for the Corporate EBITDA objective:

For 2025, the following performance levels were established for the Corporate Free Cash Flow objective:

² Corporate EBITDA and Corporate Free Cash Flow are non-GAAPmeasures. See Appendix A for definitions. For purposes of the annual incentive awards, Corporate Net Income is a non-GAAP measure defined as Adjusted Net Income (as defined in Appendix A), but adjusted to exclude the impact of certain projects that were not indicative of the Company's core operating results.

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The Corporate Safety metric evaluates achievement of certain personal and process safety goals and consists of the total recordable injury rate (TRIR), which is the number of work-related recordable injuries per 100 full-time workers during a one-year period, and Tier 1 and Tier 2 process safety events, as defined under API RP 754, the benchmarking standard used by the American Chemistry Council.

The Corporate Performance Objectives set forth above constituted 100% of the corporate performance goals for the annual incentive awards for all NEOs (other than Messrs. Moriarty and Stepan). The Corporate Performance Objectives of the annual incentive awards for each of Messrs. Moriarty and Stepan were based 70% on the company-wide Corporate Performance Objectives set forth above and 30% on operating income of the business segment for which he is responsible.

The following table shows the Company's performance against the Corporate Net Income, Corporate EBITDA, and Corporate Free Cash Flow (as well as the relative weighting of each metric) for 2025. With respect to the Corporate Safety objective, the Committee determined a payout at 50% of target was appropriate as a result of record safety performance that fell slightly below the Company's rigorous safety goal:

Based on the results above, the overall payout percentage for the company-wide Corporate Performance Objectives was 24.5%. The combined Corporate Performance Objective payout percentage based on the company-wide objectives set forth above (subject to different weighting) and the relevant business segment's operating income was 19.8% for Mr. Moriarty and 29.8% for Mr. Stepan.

Individual Performance Objectives

Each NEO's annual incentive pool is determined based on the Company's achievement of Corporate Performance Objectives. Each NEO's annual incentive payout may be increased or decreased based on the NEO's achievement of Individual Performance Objectives. The President and Chief Executive Officer and the Committee agreed upon the Individual Performance Objectives for the President and Chief Executive Officer at the beginning of 2025. For executives other than the Chief Executive Officer, the Chief Executive Officer and the executive agree upon Individual Performance Objectives at the beginning of each calendar year. These Individual Performance Objectives may either be financial objectives for a particular business segment or function, or achievement of certain strategic objectives specific to their function and responsibility. Mr. Rojo's Individual Performance Objectives as Chief Executive Officer include specific financial targets, expressed as threshold, target, and maximum levels and enhancing long-term Company performance by championing core culture and values, including safety, compliance, employee engagement, leadership development, and accountability, as well as specific operational objectives in areas such as volume production targets and reduction of unplanned downtime, growth objectives such as volume growth targets, and specific customer-focused objectives. For each business segment leader, the financial performance of the executive's segment comprises a significant portion of the executive's Individual Performance Objectives.

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Based on each NEO's individual performance in 2025, the following modifiers were applied:

The following chart reflects the annual incentive award for each NEO for 2025.

Long-Term Incentive Compensation

The Committee typically grants equity awards annually to the NEOs under the Company's long-term incentive plan. In 2025, the Committee reviewed and approved an allocation of long-term incentives for Mr. Rojo at approximately 25% of the total grant value as SARs, approximately 25% of the total grant value as RSUs and approximately 50% of the total grant value as performance shares. In 2025, the Committee reviewed and approved an allocation of long-term incentives for the remaining NEOs at approximately 25% of the total grant value as SARs, approximately 50% of the total grant value as RSUs and approximately 25% of the total grant value as performance shares to promote retention of executives, to reward outstanding Company performance and to encourage a focus on the Company's long-term financial results.

The chart below shows the number of each type of equity award that the Committee granted to the NEOs as part of the annual 2025 equity grant. The number of SARs granted was calculated by dividing the amounts in the table above by the Black-Scholes value of a SAR on the date of the grant. The number of RSUs and the target number of performance shares granted were calculated by dividing the amounts in the table above by the average of the opening price and closing price of the Company's common stock on the date of the grant.

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The grants of SARs, RSUs and performance share awards to the NEOs are shown in the Grants of Plan-Based Awards Table. The Committee believes that the mix of such awards provides long-term incentive compensation that is market competitive to attract and retain executives who drive the long-term growth of the Company and further align the interests of those executives with the interests of the Company's stockholders.

Stock Appreciation Rights

SARs are granted annually at the average of the opening price and closing price of Common Stock on the date of the grant and have a ten-yearterm. SARs vest ratably over a three-year period and are settled in stock.

Restricted Stock Units

RSUs are granted annually based on the average of the opening price and closing price of Common Stock on the date of the grant. RSUs vest ratably over a three-year period and are settled in stock.

Performance Shares

Performance shares are contingently awarded at a target number of shares and subject to certain performance conditions established by the Committee. The Committee chose Corporate Net Income as a performance measure because the Company uses net income as an important indicator of business performance. The Company uses an adjusted measure, rather than reported net income, because the adjusted measure excludes items that may not be indicative of the Company's core operating results. For purposes of the performance shares, Corporate Net Income is a non-GAAP measure defined as set forth above for purposes of the annual incentive awards; an additional adjustment was made with respect to performance share awards to include a portion of the proceeds from the sale of the Lake Providence, Louisiana plant. The Committee determined it was appropriate to include a portion of such sale proceeds in measuring performance under the 2025 long-term incentive program (performance shares) in order to recognize the plant sale's contribution to the Company's long-term performance.

The initial target number of shares may increase or decrease by up to 50% based on the Company's Corporate Net Income results for the calendar year in which the grant is made versus Threshold, Target and Maximum Corporate Net Income objectives. If the Company's Corporate Net Income result for such year is below the Threshold objective, then the performance shares are forfeited entirely. If the Company's Corporate Net Income result for such year exceeds the Maximum objective, then the target number of shares will be increased by 50%. Following completion of the three-year performance period, the number of shares may further increase or decrease by up to 30%, based on a modifier determined by the Company's Corporate Return on Invested Capital ("ROIC") for the third year of the three-year performance period.³ For performance shares granted prior to 2024, the modifier is based on the Company's three-year average Corporate ROIC for the applicable three-year performance period.

For the performance shares granted in 2025, the Committee set the following Corporate Net Income objectives:

³ Return on Invested Capital is a non-GAAPmeasure. See Appendix A for a definition.

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Human Capital and Compensation Committee Report

The Human Capital and Compensation Committee has reviewed and discussed the Compensation Discussion and Analysis with the management of the Company. Based on this review and discussion, we have recommended to the Board of Directors that the Compensation Discussion and Analysis be included in the proxy statement and in the Company's Annual Report on Form 10-Kfor the year ended December 31, 2025.

   HUMAN CAPITAL AND COMPENSATION COMMITTEE

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2025 Summary Compensation Table

The table below summarizes the total compensation paid to or earned by each of the NEOs for the fiscal year ended on December 31, 2025 (and, to the extent applicable, December 31, 2024, and December 31, 2023). Additional information related to each component of compensation for the NEOs is provided above in the Compensation Discussion and Analysis.

(1) Mr. Velasquez was appointed Vice President and Chief Financial Officer effective July 15, 2025. Mr. Hinrichsen was promoted to Vice President and Interim Chief Financial Officer on October 29, 2024. Mr. Hinrichsen served as the Interim Chief Financial Officer until July 14, 2025, and Global Vice President, Finance and Investor Relations until his resignation on October 31, 2025.

(2) No information is provided with respect to the 2024 and 2023 fiscal years for Mr. Velasquez because he was not an NEO prior to the 2025 fiscal year. No information is provided with respect to 2024 and 2023 fiscal years for Mr. Stepan because he was not an NEO prior to the 2025 fiscal year.

(3) Amounts for 2025 include (a) the grant date fair value of RSUs granted during the fiscal year ended December 31, 2025, calculated in accordance with FASB ASC Topic 718, and (b) performance share awards that are subject to performance-based vesting conditions and reflect the probable outcome award value (target) at the date of the grant in accordance with FASB ASC Topic 718, excluding the effect of estimated forfeitures. See Note 11, Stock-based Compensation, to the consolidated financial statements included in the Company's Annual Report on Form 10-Kfor the year ended December 31, 2025, for a discussion of relevant assumptions used in calculating the fair values pursuant to FASB ASC Topic 718. These performance share awards are subject to achievement of the performance conditions as described in the section above entitled "Compensation

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Discussion and Analysis-Elements of Compensation-Long-Term Incentive Compensation." The maximum grant date values, assuming achievement of the highest level of performance conditions, would be:

(4) Amounts for 2025 include the grant date fair value of SARs granted during the fiscal year ended December 31, 2025, calculated in accordance with FASB ASC Topic 718. See Note 11, Stock-based Compensation, to the consolidated financial statements included in the Company's Annual Report on Form 10-Kfor the year ended December 31, 2025, for a discussion of relevant assumptions used in calculating the fair values pursuant to FASB ASC Topic 718.

(5) Amounts for 2025 include Company contributions (including profit-sharing contributions) to each NEO's defined contribution accounts as follows: Mr. Rojo: $76,993; Mr. Velasquez: $63,443; Mr. Haire: $33,939; Mr. Moriarty: $49,965; Mr. Stepan: $42,147; and Mr. Hinrichsen: $17,491. Amounts for 2025 for NEOs (other than Messrs. Velasquez and Hinrichsen) also include long-term disability insurance premiums. Amounts for 2025 include the following perquisites and other personal benefits: for all NEOs other than Mr. Hinrichsen, airline club memberships; for all NEOs (other than Messrs. Velasquez and Hinrichsen), personal use of Company-leased vehicles; for Messrs. Haire and Moriarty, spousal travel; for Mr. Stepan and Mr. Hinrichsen, personal and family use of the Company-owned condominium; and for Mr. Velasquez, relocation ($10,000) and moving expenses ($39,622).

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2025 Grants of Plan-Based Awards

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Outstanding Equity Awards at 2025 Fiscal Year-End

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2025 Option Exercises and Stock Vested