SCHEDULE 13G/A 0001193125-24-026674 0001032282 XXXXXXXX LIVE 12 Common Stock, par value $0.01 per share 12/31/2025 0001402436 SS&C Technologies Holdings, Inc. 78467J100 80 Lamberton Road Windsor CT 06095 Rule 13d-1(d) William C. Stone X1 35202277 0 35202277 0 35202277 N 14.3 IN SS&C Technologies Holdings, Inc. 80 Lamberton Road, Windsor, Connecticut 06095 William C. Stone c/o SS&C Technologies Holdings, Inc., 80 Lamberton Road, Windsor, Connecticut 06095 United States of America Y 35,202,277 shares of Common Stock (consisting of 32,447,241 shares outstanding and an additional 2,775,036 shares representing RSUs and options to purchase shares vested as of December 31, 2025 and within 60 days thereafter). 14.3 35,202,277 shares of Common Stock 0 shares 35,202,277 shares of Common Stock 0 shares Y Y Y Y Y Y William C. Stone /William C. Stone/ 02/09/2026