Alphamab Oncology filed a Next Day Disclosure Return with the Hong Kong Stock Exchange on 21 May 2026, detailing a minor expansion of its issued share base following employee option exercises under the Post-IPO Share Option Scheme adopted on 25 May 2020 and amended on 12 June 2024.

• New shares issued: 88,000 ordinary shares (0.09 million), representing 0.0091 % of the company’s pre-event issued share capital (excluding treasury shares).

• Issue price: HKD 4.7895 per share (volume-weighted average).

• Share capital movement: – Opening balance as at 30 April 2026: 968.57 million issued shares (excluding 5.72 million treasury shares), total 974.29 million shares outstanding. – Closing balance as at 21 May 2026: 968.66 million issued shares (excluding 5.72 million treasury shares), total 974.38 million shares outstanding.

• Treasury shares: No changes; no shares were repurchased, redeemed, or sold from treasury during the period.

The board of directors confirmed that the share issuance complied with all applicable listing rules, legal requirements, and internal authorisations, and that all proceeds have been duly received.