SCHEDULE 13G 0001409751 XXXXXXXX LIVE Common Stock, par value $0.01 per share 08/11/2025 0001941365 MasterBrand, Inc. 57638P104 3300 Enterprise Parkway Suite 300 Beachwood OH 44122 Rule 13d-1(c) Coliseum Capital Management, LLC b DE 0 6960829 0 6960829 6960829 N 5.5 IA Coliseum Capital, LLC b DE 0 5700896 0 5700896 5700896 N 4.5 OO Coliseum Capital Partners, L.P. b DE 0 5700896 0 5700896 5700896 N 4.5 PN Adam Gray b X1 0 6960829 0 6960829 6960829 N 5.5 IN Christopher Shackelton b X1 0 6960829 0 6960829 6960829 N 5.5 IN MasterBrand, Inc. 3300 Enterprise Parkway, Suite 300Beachwood, Ohio 44122 This Schedule 13G is being filed on behalf of Coliseum Capital Management, LLC ("CCM"), Coliseum Capital LLC ("CC"), Coliseum Capital Partners, L.P. ("CCP"), Adam Gray ("Gray") and Christopher Shackelton ("Shackelton" and together with CCM, CC, CCP and Gray, the "Reporting Persons"). The business address of the Reporting Persons is 105 Rowayton Avenue, Rowayton, CT 06853. (i) CCM is a Delaware limited liability company; (ii) CC is a Delaware limited liability company; (iii) CCP is a Delaware limited partnership; (iv) Gray is a United States citizen; and (v) Shackelton is a United States citizen. Y (i) CCM is the beneficial owner of 6,960,829 shares of common stock, $0.01 par value per share ("Common Stock"); (ii) CC is the beneficial owner of 5,700,896 shares of Common Stock; (iii) CCP is the beneficial owner of 5,700,896 shares of Common Stock; (iv) Gray is the beneficial owner of 6,960,829 shares of Common Stock; and (v) Shackelton is the beneficial owner of 6,960,829 shares of Common Stock. (i) CCM - 5.5%; (ii) CC - 4.5%; (iii) CCP - 4.5%; (iv) Gray - 5.5%; and (v) Shackelton - 5.5%. The ownership percentage of each Reporting Person has been calculated based on an assumed total of 126,730,924 shares of Common Stock issued and outstanding as of August 1, 2025, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 6, 2025. (i) 0 shares of Common Stock for CCM; (ii) 0 shares of Common Stock for CC; (iii) 0 shares of Common Stock for CCP; (iv) 0 shares of Common Stock for Gray; and (v) 0 shares of Common Stock for Shackelton. (i) 6,960,829 shares of Common Stock for CCM; (ii) 5,700,896 shares of Common Stock for CC; (iii) 5,700,896 shares of Common Stock for CCP; (iv) 6,960,829 shares of Common Stock for Gray; and (v) 6,960,829 shares of Common Stock for Shackelton. (i) 0 shares of Common Stock for CCM; (ii) 0 shares of Common Stock for CC; (iii) 0 shares of Common Stock for CCP; (iv) 0 shares of Common Stock for Gray; and (v) 0 shares of Common Stock for Shackelton. (i) 6,960,829 shares of Common Stock for CCM; (ii) 5,700,896 shares of Common Stock for CC; (iii) 5,700,896 shares of Common Stock for CCP; (iv) 6,960,829 shares of Common Stock for Gray; and (v) 6,960,829 shares of Common Stock for Shackelton. Y Y Y N CCM is the investment adviser to CCP, which is an investment limited partnership. CC is the General Partner of CCP. Gray and Shackelton are the managers of CC and CCM. The Reporting Persons may be deemed to be members of a group with respect to the Common Stock owned of record by CCP and a separate account managed by CCM (the "Separate Account"). CCP is the record owner of 5,700,896 shares of Common Stock and the Separate Account is the record owner of 1,259,933 shares of Common Stock. Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. Coliseum Capital Management, LLC Adam Cina 08/18/2025 Coliseum Capital, LLC Adam Cina 08/18/2025 Coliseum Capital Partners, L.P. Adam Cina 08/18/2025 Adam Gray Adam Cina 08/18/2025 Christopher Shackelton Adam Cina 08/18/2025