Jacobio Pharmaceuticals Group Co., Ltd. (Jacobio-B) disclosed a share buy-back executed on 15 June 2026 under its existing repurchase mandate:

• Transaction details: 111,600 ordinary shares were repurchased on the Hong Kong Stock Exchange at prices between HK$4.44 and HK$4.49, with a volume-weighted average cost of HK$4.4545 per share. Aggregate consideration amounted to HK$0.50 million.

• Capital impact: – Issued shares (excluding treasury) fell by 0.01424 % to 783.52 million. – Treasury shares increased to 8.24 million. – Total issued shares remained unchanged at 791.76 million, as the repurchased shares are being held in treasury and have not been cancelled.

• Repurchase mandate utilisation: – The current mandate, approved on 5 June 2026, authorises buy-backs of up to 78.37 million shares. – Cumulative repurchases under this mandate now total 207,300 shares, equivalent to 0.03 % of the company’s issued shares at the mandate date, leaving a balance of roughly 78.17 million shares available.

• Moratorium: In accordance with Hong Kong Listing Rules, Jacobio-B is restricted from issuing new shares or disposing of treasury shares until 15 July 2026.

The company confirms that all repurchases complied with the Hong Kong Stock Exchange’s Main Board Rules and that there have been no material changes to the previously published explanatory statement regarding the share buy-back programme.