BIG: Change in shareholding of principal shareholder (Tran Sinh Vuong)

- Name of issuer: Big Invest Group Joint Stock Company
- Stock code: BIG
- Securities type: common stock
- Name of principal shareholder: Tran Sinh Vuong
- Number of shares held by the principal shareholder before transaction: 2,695,994 shares (16.86%)
- Number of shares disposed: 147,994 shares
- Total holding following transaction and total percentage following transaction: 2,548,000 shares (15.94%)
- Purpose of transaction: Sell ​​shares
- Date of transaction: 12/09/2025.