X0202 SCHEDULE 13G/A 0001293451 XXXXXXXX LIVE 1 Class A Ordinary Shares 06/30/2026 0002088256 Horizon Quantum Holdings Ltd. Y4000A102 29 MEDIA CIRCLE #05-22 SINGAPORE U0 138565 Rule 13d-1(c) Tencent Holdings Ltd E9 3800438.00 0.00 3800438.00 0.00 3800438.00 N 11.1 CO THL A12 Limited D8 3800438.00 0.00 3800438.00 0.00 3800438.00 N 11.1 CO Horizon Quantum Holdings Ltd. 29 Media Cir. #05-22, Singapore, 138565 Tencent Holdings Limited THL A12 Limited For both Tencent Holdings Limited and THL A12 Limited: 29/F, Three Pacific Place No. 1 Queen's Road East Wanchai, Hong Kong Tencent Holdings Limited - Cayman Islands THL A12 Limited - British Virgin Islands Y THL A12 Limited beneficially owns 3,800,438 Class A Ordinary Shares. Tencent Holdings Limited may be deemed to have beneficial ownership of 3,800,438 Class A Ordinary Shares beneficially owned by THL A12 Limited, which is a direct wholly-owned subsidiary of Tencent Holdings Limited. See row 11 of the cover page of each reporting person. The foregoing calculation is based on an aggregate of 34,227,495 Class A Ordinary Shares outstanding as of June 30, 2026, as reported in the unaudited condensed consolidated interim financial statements of the Issuer filed as Exhibit 99.1 to the Issuer's current report on Form 6-K furnished to the U.S. Securities and Exchange Commission on August 4, 2026. See row 5 of the cover page for each reporting person. See row 6 of the cover page of each reporting person. See row 7 of the cover page of each reporting person. See row 8 of the cover page of each reporting person. 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. 99.1 Joint Filing Agreement (previously filed as Exhibit 99.1 to Schedule 13G filed by the reporting persons with the Securities and Exchange Commission on March 25, 2026). Tencent Holdings Ltd /s/ Ma Huateng 08/14/2026 THL A12 Limited /s/ Li Qingjie 08/14/2026