MASCO CORP DE

APPENDIX C — AMENDMENTS TO THE COMPANY’S CERTIFICATE OF INCORPORATION TOPHASE-OUT THE CLASSIFICATION OF THE BOARD OF DIRECTORS OVER A THREE-YEAR PERIOD AND PROVIDE FOR THE ANNUAL ELECTION OF DIRECTORS

SEVENTH: (a)Until the 2028 annual meeting of stockholders, the directors of the Corporation (other than those directors elected by the holders of any series of Preferred Stock provided for or fixed pursuant to the provisions of Article Fourth B hereof (the “Preferred Stock Directors”)) shall be divided into three classes. Commencing with the 2026 annual meeting of stockholders, directors of the Corporation (other than any Preferred Stock Director) shall be elected as follows: (i) directors elected at the 2026 annual meeting of stockholders to succeed those whose term expires at such meeting shall hold office for a term expiring at the annual meeting of stockholders to be held in 2027; (ii) directors elected at the 2027 annual meeting of stockholders to succeed those whose term expires at such meeting shall hold office for a term expiring at the annual meeting of stockholders to be held in 2028; and (iii) beginning with the 2028 annual meeting of stockholders, all directors elected at an annual meeting of stockholders to succeed those whose term expires at such meeting shall hold office for a term expiring at the next annual meeting of stockholders.

Each director shall hold office until the annual meeting of the stockholders for the year in which his or her term expires and until such director’s successor is duly elected and qualified, or until such director’s earlier death, resignation, disqualification or removal. A director may resign at any time upon notice to the Corporation as provided in the Corporation’s Bylaws.

Except for any Preferred Stock Director, any director or the entire Board of Directors may be removed from office at any time, (i) in the event such removal is prior to the 2028 annual meeting of stockholders, only for cause, and (ii) in the event such removal is after to the 2028 annual meeting of stockholders, with or without cause.

Subject to the terms of any one or more series of Preferred Stock then outstanding, any vacancy on the Board of Directors, by reason of death, resignation, retirement, disqualification or removal or otherwise, and any newly created directorship that results from an increase in the number of directors, shall be filled only by a majority of the Board of Directors then in office, even if less than a quorum, or by a sole remaining director. Any director elected to the Board of Directors in accordance with this Paragraph (a) Seventh shall hold office (i) in the event of a new directorship created or vacancy occurring prior to the 2028 annual meeting of stockholders, for a term that shall coincide with the remaining term of the class of directors in which the new directorship was created or the vacancy occurs, and (ii) in the event of a new directorship created or vacancy occurring after the 2028 annual meeting of stockholders, until the next annual meeting of stockholders.

The business and affairs of the Corporation shall be managed by or under the direction of a Board of Directors consisting of not less than five nor more than twelve directors, the exact number of directors to be determined from time to time by resolution adopted by affirmative vote of a majority of the entire Board of Directors. The directors shall be divided into three classes, designated Class I, Class II and Class III. Each class shall consist, as nearly as may be possible, of one-third of the total number of directors constituting the entire Board of Directors. At the 1988 Annual Meeting of stockholders, Class I directors shall be elected for a one-year term, Class II directors for atwo-year term and Class III directors for a three-year term. At each succeeding Annual Meeting of stockholders beginning in 1989, successors to the class of directors whose term expires at that annual meeting shall be elected for a three-year term. If the number of directors is changed, any increase or decrease shall be apportioned among the classes so as to maintain the number of directors in each class as nearly equal as possible, and any additional director of any class elected to fill a vacancy resulting from an increase in such class shall hold office for a term that shall coincide with the remaining termof that class, but in no case will a decrease in the number of directors shorten the term of any incumbent director. A director shall hold office until the annual meeting for the year in which his term expires and until his successor shall be elected and shall qualify, subject, however, to prior death, resignation, retirement or removal from office. Except as otherwise required by law, any vacancy on the Board of Directors that results from an increase in the number of directors shall be filled only by a majority of the Board of Directors then in office, provided that a quorum is present, and any other vacancy occurring in the Board of Directors shall be filled only by a majority of the directors then in office, even if less than a quorum, or by a sole remaining director. Any director elected to fill a vacancy not resulting from an increase in the number of directors shall serve for the remaining term of his predecessor.

Notwithstanding the foregoing, whenever the holders of any one or more classes or series of preferred stock or any other class of stock issued by the Corporation shall have the right, voting separately by class or series, to elect directors at an annual or special meeting of stockholders, the election, term of office, filling of vacancies and other features of such directorships shall be governed by the terms of the Certificate of Designation with respect to such stock, such directors so elected shall not be divided into classes pursuant to this Article SEVENTH, and the number of such directors shall not be counted in determining the maximum number of directors permitted under the foregoing provisions of this Article SEVENTH, in each case unless expressly provided by such terms.

17450 COLLEGE PARKWAY

LIVONIA, MI 48152

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V65753-P24985 KEEP THIS PORTION FOR YOUR RECORDS

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V65754-P24985

MASCO CORPORATION THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS FOR THE ANNUAL MEETING OF STOCKHOLDERS MAY 9, 2025 The undersigned stockholder(s) hereby appoint(s) Keith J. Allman and Kenneth G. Cole, or either of them, as proxy holders, each with the power to appoint his substitute, and hereby authorize(s) them to represent and to vote, as designated on the reverse side of this proxy, all of the shares of Common Stock of MASCO CORPORATION that the stockholder(s) is/are entitled to vote at the Annual Meeting of Stockholders (the “Meeting”) to be held at 8:30 A.M. Eastern Time on Friday, May 9, 2025, virtually at www.virtualshareholdermeeting.com/MAS2025, and any adjournment or postponement thereof, and to vote in their discretion on any other matters that may come before the meeting or any adjournment or postponement thereof. THIS PROXY, WHEN PROPERLY EXECUTED, WILL BE VOTED AS DIRECTED BY THE STOCKHOLDER(S). IF NO SUCH DIRECTIONS ARE MADE, THIS PROXY WILL BE VOTED “FOR” THE ELECTION OF THE NOMINEES LISTED IN PROPOSAL 1 AND “FOR” PROPOSALS 2, 3, 4, 5 AND 6. The undersigned hereby acknowledge(s) prior receipt of a Notice of Annual Meeting of Stockholders of the Company called for May 9, 2025, the Proxy Statement for the Annual Meeting and the 2024 Annual Report to Stockholders. PLEASE MARK, SIGN, DATE AND RETURN THIS PROXY CARD PROMPTLY USING THE ENCLOSED REPLY ENVELOPE. Continued and to be signed on reverse side