SCHEDULE 13G/A 0001104659-18-059730 0001232258 XXXXXXXX LIVE 7 Common Stock, $0.0001 par value 09/30/2025 0001722964 Y-mAbs Therapeutics, Inc. 984241109 202 Carnegie Center Suite 301 Princeton NJ 08540 Rule 13d-1(c) HBM Healthcare Investments (Cayman) Ltd. E9 0.00 0.00 0.00 0.00 0.00 N 0 CO Voting and investment power over the shares held by HBM Healthcare Investments (Cayman) Ltd. is exercised by the board of directors of HBM Healthcare Investments (Cayman) Ltd. (the "Board"). The Board consists of Jean-Marc LeSieur, Richard H. Coles, Sophia Harris, Dr. Andreas Wicki, Mark Kronenfeld, M.D., and Richard Paul Woodhouse, none of whom has individual voting or investment power with respect to the shares. Y-mAbs Therapeutics, Inc. 202 Carnegie Center, Suite 301, Princeton, NJ, 08540 HBM Healthcare Investments (Cayman) Ltd. (the "Reporting Person") Governors Square, 23 Lime Tree Bay Avenue, PO Box 30852, Grand Cayman, KY1-1204, Cayman Islands Cayman Islands, British West Indies Y As of September 30, 2025, the Reporting Person may be deemed the beneficial owner of 0 shares of Common Stock. 0% 0 0 0 0 N Y Y Y Y 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. HBM Healthcare Investments (Cayman) Ltd. /s/ Jean-Marc LeSieur 11/14/2025