CStone Pharmaceuticals (CStone Pharma) disclosed a series of on-market share buybacks carried out between 15 June and 25 June 2026. A total of 4.18 million ordinary shares have been repurchased for cancellation but were still pending cancellation as at 25 June 2026. The transactions represent 0.26 % of the company’s 1.60 billion issued shares.

The volume-weighted average repurchase price across the seven trading sessions was HKD 4.67, implying an aggregate cash outlay of HKD 19.50 million. Daily volumes and prices were as follows: • 15 Jun: 6,000 shares at HKD 4.66 • 16 Jun: 1.33 million shares at HKD 4.68 • 17 Jun: 1.00 million shares at HKD 4.62 • 18 Jun: 500,000 shares at HKD 4.63 • 22 Jun: 500,000 shares at HKD 4.70 • 24 Jun: 500,000 shares at HKD 4.80 • 25 Jun: 340,000 shares at HKD 4.59

On 25 June 2026 alone, 340,000 shares were bought back at prices ranging from HKD 4.53 to HKD 4.60, costing HKD 1.56 million.

The buybacks were executed under a mandate approved on 23 June 2026, which authorises the company to repurchase up to 159.74 million shares. As of the latest trading day disclosed, 840,000 shares (0.05 % of the company’s issued share base on the mandate date) have been repurchased under this authorisation.

In accordance with Hong Kong listing rules, CStone Pharma is subject to a moratorium on issuing new shares until 25 July 2026 following the latest repurchase.