SCHEDULE 13D/A 0002037164 XXXXXXXX LIVE 3 Class A Common Stock, $0.0001 Par Value per share 08/21/2025 false 0001823144 20459V105 CompoSecure, Inc.

309 Pierce Street Somerset NJ 08873

Thomas R. Knott (212) 256-8405 c/o Resolute Compo Holdings LLC 445 Park Avenue, Suite 5B New York NY 10022 0002037164 N Resolute Compo Holdings LLC PF OO N DE 0.00 49290409.00 0.00 49290409.00 49290409.00 N 44.3 OO Consists of 49,290,409 shares of Class A Common Stock, $0.0001 par value per share, issued by CompoSecure, Inc. (the "Class A Common Stock"), held of record by Resolute Compo Holdings LLC ("Resolute Compo Holdings"). Row (13) is based upon 111,388,134 shares of Class A Common Stock that were outstanding as of August 22, 2025. Y Tungsten 2024 LLC PF N DE 0.00 49937302.00 0.00 49937302.00 49937302.00 N 44.8 OO Consists of (i) 646,893 shares of Class A Common Stock held of record by Tungsten 2024 LLC ("Tungsten"), and (ii) 49,290,409 shares of Class A Common Stock held of record by Resolute Compo Holdings. Tungsten is the managing member of Resolute Compo Holdings, John Cote is the manager of Tungsten and Thomas Knott is a member of Resolute Compo Holdings. Tungsten, as managing member, has the right to vote and dispose of the shares of Class A Common Stock reported herein, subject to certain consultation rights held by Mr. Knott. Accordingly, Tungsten, Resolute Holdings, Mr. John Cote and Mr. Knott may each be deemed to share beneficial ownership of the shares of Class A Common Stock held of record by Resolute Compo Holdings, and Tungsten, Mr. John Cote and Mr. Knott may each be deemed to share beneficial ownership of the shares of Class A Common Stock held of record by Tungsten. Row (13) is based upon 111,388,134 shares of Class A Common Stock that were outstanding as of August 22, 2025. Y Thomas R. Knott OO N X1 0.00 49937302.00 0.00 49937302.00 49937302.00 N 44.8 IN Consists of (i) 646,893 shares of Class A Common Stock held of record by Tungsten, and (ii) 49,290,409 shares of Class A Common Stock held of record by Resolute Compo Holdings. Tungsten is the managing member of Resolute Compo Holdings, John Cote is the manager of Tungsten and Thomas Knott is a member of Resolute Compo Holdings. Tungsten, as managing member, has the right to vote and dispose of the shares of Class A Common Stock reported herein, subject to certain consultation rights held by Mr. Knott. Accordingly, Tungsten, Resolute Holdings, Mr. John Cote and Mr. Knott may each be deemed to share beneficial ownership of the shares of Class A Common Stock held of record by Resolute Compo Holdings, and Tungsten, Mr. John Cote and Mr. Knott may each be deemed to share beneficial ownership of the shares of Class A Common Stock held of record by Tungsten. Row (13) is based upon 111,388,134 shares of Class A Common Stock that were outstanding as of August 22, 2025. Y John D. Cote OO N X1 1500000.00 49937302.00 1500000.00 49937302.00 51437302.00 N 46.2 IN Consists of (i) 646,893 shares of Class A Common Stock held of record by Tungsten, (ii) 49,290,409 shares of Class A Common Stock held of record by Resolute Compo Holdings and (iii) 1,500,000 shares of Class A Common Stock held by Ridge Valley LLC. Tungsten is the managing member of Resolute Compo Holdings, John Cote is the manager of Tungsten and Thomas Knott is a member of Resolute Compo Holdings. Tungsten, as managing member, has the right to vote and dispose of the shares of Class A Common Stock reported herein, subject to certain consultation rights held by Mr. Knott. Accordingly, Tungsten, Resolute Holdings, Mr. John Cote and Mr. Knott may each be deemed to share beneficial ownership of the shares of Class A Common Stock held of record by Resolute Compo Holdings, and Tungsten, Mr. John Cote and Mr. Knott may each be deemed to share beneficial ownership of the shares of Class A Common Stock held of record by Tungsten. Row (13) is based upon 111,388,134 shares of Class A Common Stock that were outstanding as of August 22, 2025. Class A Common Stock, $0.0001 Par Value per share CompoSecure, Inc. 309 Pierce Street Somerset NJ 08873 This Amendment No. 3 to Schedule 13D (this "Amendment No. 3") relates to the Class A Common Stock, par value $0.0001 per share (the "Class A Common Stock") of CompoSecure, Inc., a Delaware corporation (the "Issuer") and amends the initial statement on Schedule 13D filed by the Reporting Persons on September 19, 2024 (the "Initial Statement" and, as amended by that certain Amendment No. 1 filed on November 29, 2024, Amendment No. 2 filed on February 14, 2025 and this Amendment No. 3, the "Schedule 13D"). Capitalized terms used but not defined herein shall have the meanings ascribed to them in the Initial Statement. This Amendment No. 3 is being filed to amend the Schedule 13D solely due to a change in the aggregate number of Class A Common Stock outstanding and not due to any transaction by the Reporting Persons. See Row (1) of each Reporting Person's cover page. The principal business office of the Reporting Persons is 445 Park Avenue, Suite 5B, New York, NY 10022. No change. No change. No change. No change. Item 3 is hereby amended and supplemented as specified in Appendix A. Item 5(a) is hereby amended and restated to read in its entirety as found in Appendix A. Item 5(b) is hereby amended and restated to read in its entirety as found in Appendix A. None. None. Not applicable. Resolute Compo Holdings LLC /s/ John D. Cote 08/22/2025 Tungsten 2024 LLC /s/ John D. Cote 08/22/2025 Thomas R. Knott /s/ Thomas R. Knott 08/22/2025 John D. Cote /s/ John D. Cote 08/22/2025