Viet Nam Securities Depository and Clearing Corporation (VSDC) would like to announce the record date of corporate action processing for the Securities registering institution as follows:

+ Right code: MIRDSH251
+ ISIN code: VNMIRDSH2512
(Effective date of code allocation: 24/10/2025; effective date of code cancellation: 20/11/2025)       
+ Planned quantity of issued shares: 25,000,000 shares
+ Issue price: 10,000 VND/share
+ Execution rate: 1:2.5 (shareholders are entitled to 1 right for each share that they own and to buy 250 new shares for every 100 rights).
- Principle of rounding, handling fractional shares: The number of shares each shareholder is entitled to buy will be rounded down to the whole number. The fractional will be aggregated and handled according to the plan on handling fractional shares and remaining unsold shares.
For example: Shareholder A owns 255 shares on the record date to exercise the right to buy shares. With the right allocation ratio of 1:2.5, the number of shares that shareholder A can buy is 255 * 2.5/1 = 637.5 shares. According to the rounding principle, shareholder A will be entitled to buy 637 new shares. The fractional 0.5 shares arising from the rounding down of the shareholder will be included in the remaining undistributed shares and the Board of Directors (BoD) will decide the handling plan.
+Principle for handling the remaining shares that have not been fully distributed: The remaining shares that have not been fully distributed  include:
(i) The remaining shares that the shareholders and/or transferees of the right  do not exercise their right to purchase in full or only exercise their right in part, or do not make payment within the prescribed time limit and/or due to other reasons;
(ii) The fractional number of shares (if any) arising from rounding down when calculating the shares to be purchased by existing shareholders.
+ The BoD decides to distribute all remaining shares to other investors at a price of VND 10,000/share. The remaining shares, if distributed further, will be restricted from transfer within 01 year from the end date of the offering.
+ The distribution of the remaining undistributed shares to other investors has to meet the following conditions:
*    Comply with the regulations on cross-ownership in Article 195 of the Enterprise Law.
*    Comply with the regulations on handling shares that investors do not register to buy, do not pay for, and odd shares in Article 42 of Decree 155/2020/ND-CP.
+ Criteria for selecting investors to distribute the remaining shares:
*      Investors with sufficient financial capacity, making timely payments to purchase shares, ensuring the progress of the offering.
*     Prioritize investors who are existing shareholders and can contribute to the development of Dong Son Infrastructure Investment JSC in the future.
*      Accept the condition of restricting the transfer of shares within one year from the end date of the offering.
+ After implementing the above plan to handle remaining shares, if there are still remaining shares, these shares will be purchased by the Underwriter according to the commitment in the Underwriting Contract/Underwriting Commitment at the distribution price of VND 10,000/share. These shares will not be subject to transfer restrictions.
- Regulations on rights transfer:
+ Time for transfer of right issue: From 24/10/2025 to 12/11/2025.
+ Shareholders owning right issues can transfer their  rights to others within the prescribed time and only transfer once, the transferee of rights will not be allowed to transfer to a third party.
+ Existing shareholders can only transfer their  rights to domestic institutions and individuals.
- Regulations on subscribed securities:
+ Time for subscription and payment: From 24/10/2025 to 17/11/2025.
+ Subscribed securities are freely transferable.
- Place for implementation:
+ The holders whose shares have been deposited have to make transfer of purchase right, subscription and payment at the depository member where they opened depository account.
+ The holders whose shares have not been deposited will make right transfer, subscription and payment at Dong Son Infrastructure Investment Joint Stock Company (11th Floor, No. 02 Nguyen Thi Due Street, Yen Hoa Ward, Hanoi City - Phone number: 024 3556 7799) on working days of the week, starting from October 24, 2025. ID card, Certificate of Share Ownership have to be presented. 
- Information on blockade account for subscription:
+ Account holder: Dong Son Infrastructure Investment Joint Stock Company
+ Account number: 119003017291
+ Account opening place: Vietinbank – Dong Da Branch.
- Information on VSDC's account for cash transferring:
+ Account name: Viet Nam Securities Depository and Clearing Corporation
+ Account number: 1220173177
+ At the bank: Bank for Investment and Development of Vietnam – Ha  Thanh Branch.
Coordination details and procedures for corporate action processing for holders of the above securities between VSDC, the Securities registering institution and depository members are specified in the Guideline on corporate action processing for securities holders at VSDC