SCHEDULE 13G 0001626317 XXXXXXXX LIVE Common Stock, $0.001 par value 12/31/2025 0002071288 Lumexa Imaging Holdings, Inc. 550249106 4200 Six Forks Road Suite 1000 Raleigh NC 27609 Rule 13d-1(d) Welsh, Carson, Anderson & Stowe XII, L.P. DE 0 70217616 0 70217616 70217616 N 74.3 PN WCAS XII Associates LLC DE 0 70217616 0 70217616 70217616 N 74.3 OO WCAS Management Corporation DE 0 70217616 0 70217616 70217616 N 74.3 CO Lumexa Imaging Holdings, Inc. 4200 Six Forks Road, Suite 1000, Raleigh, NC 27609 This Schedule 13G is filed by (i) Welsh, Carson, Anderson & Stowe XII, L.P. ("WCAS XII"); (ii) WCAS XII Associates LLC ("XII Associates"), as the general partner of WCAS XII; and (iii) WCAS Management Corporation ("WCAS Management"), as the investment adviser to WCAS XII (each, a "Reporting Person" and collectively, the "Reporting Persons"). The agreement among the Reporting Persons to file the Schedule 13G jointly (the "Joint Filing Agreement") is filed herewith as Exhibit A. 599 Lexington Avenue, Suite 1800, New York, NY 10022 WCAS XII is a Delaware limited partnership. XII Associates is a Delaware limited liability company. WCAS Management is a Delaware corporation. Y The information required by this paragraph is set forth in the cover pages to this Schedule 13G and is incorporated herein by reference. The shares reported herein as beneficially owned by the Reporting Persons are held by Lumexa Imaging Holdings, LLC ("Holdings LLC"). WCAS XII has the right under the LLC Agreement of Holdings LLC to designate a majority of the members of the Board of Managers of Holdings LLC and, as a result, shares beneficial ownership over the shares held by Holdings LLC. After the expiration of a 180-day lock-up period following the closing of the Issuer's initial public offering on December 12, 2025, Holdings LLC may distribute all or a portion of the shares of Common Stock it holds to its equity holders on a pro rata basis (a "Distribution"). The shares reported herein include up to 28,595,386 shares that could be received by affiliates of Welsh, Carson, Anderson & Stowe in connection with a full Distribution, as follows: (i) 17,995,515 shares that represent WCAS XII's maximum pro-rata interest in Holdings LLC; (ii) 49,981 shares that represent WCAS Management's maximum pro-rata interest in Holdings LLC; (iii) 3,282,597 shares that represent Welsh, Carson, Anderson & Stowe XII Cayman, L.P.'s maximum pro-rata interest in Holdings LLC; (iv) 526,810 shares that represent Welsh, Carson, Anderson & Stowe XII Delaware II, L.P.'s maximum pro-rata interest in Holdings LLC; (v) 3,171,591 shares that represent Welsh, Carson, Anderson & Stowe XII Delaware, L.P.'s maximum pro-rata interest in Holdings LLC; (vi) 236,854 shares that represent WCAS XII Co-Investors LLC's maximum pro-rata interest in Holdings LLC; and (vii) 3,332,038 shares that represent WCAS-Co-Invest Holdco, L.P.'s maximum pro-rata interest in Holdings LLC. Upon a full Distribution, the remaining shares set forth in the cover pages to this Schedule 13G would be distributed to persons unaffiliated with the Reporting Persons and the Reporting Persons will cease to share beneficial ownership over such shares. The information required by this paragraph is set forth in the cover pages to this Schedule 13G and is incorporated herein by reference. Percentage ownership is based on 94,565,652 shares of Common Stock outstanding after the completion of the Issuer's initial public offering, as reported in the Issuer's final prospectus on Form 424B4 dated December 10, 2025 and filed with the Securities and Exchange Commission on December 12, 2025. The information required by this paragraph is set forth in the cover pages to this Schedule 13G and is incorporated herein by reference. The information required by this paragraph is set forth in the cover pages to this Schedule 13G and is incorporated herein by reference. The information required by this paragraph is set forth in the cover pages to this Schedule 13G and is incorporated herein by reference. The information required by this paragraph is set forth in the cover pages to this Schedule 13G and is incorporated herein by reference. Y Y Y Y Y Y Exhibit A - Joint Filing Agreement Welsh, Carson, Anderson & Stowe XII, L.P. /s/ Jennifer Martin 02/13/2026 WCAS XII Associates LLC /s/ Jennifer Martin 02/13/2026 WCAS Management Corporation /s/ Jennifer Martin 02/13/2026