Trading regulations at HNX (Hanoi Stock Exchange)

1. Trading hours for listed securities
Trading occurs Monday through Friday each week, except on public holidays as defined by the Labor Law or decisions by the State Securities Commission of Vietnam.
1.1. For trading of listed stocks and ETF fund certificates

Trading Session	Time	Trading Method
Morning session	9h00 – 11h30	Continuous Matching Orders Applicable order types*: LO, MTL, MOK, MAK Negotiated Deals
Lunch Break	11h30 – 13h00
Afternoon session	13h00 – 14h30	Continuous Matching Orders Applicable order types*: LO, MTL, MOK, MAK Negotiated Deals
	14h30 – 14h45	Closing Period Regular Matching Orders Applicable order types*: LO, ATC Negotiated Deals
	14h45 – 15h00	After-Hours auction Applicable order types*: PLO Negotiated Deals

1.2. For bond trading:

Trading Session	Trading Method	Trading hour	Trading Orders
Morning session	Continuous auction I	09h00 – 11h30	Limit Orders (LO)
	Negotiated Deals	09h00 – 11h30
Lunch break between two sessions		11h30 – 13h00
Afternoon session	Continuous auction II	13h00 – 14h30
	Closing Period Regular Matching Orders	14h30-14h45
	Negotiated Deals	13h00 – 15h00

1.3. For trading on UpCom:

Trading Method	Trading hour
Continuous auction I	09h00 – 11h30
Continuous auction II	13h00 – 15h00
Negotiation auction	09h00 – 15h00

2. Matching Methods:

A. Types of trading orders:

i. Limit Orders (LO)

• A buy or sell order for securities at a specified or better price, effective from the time of entry into the trading system until the end of the trading day or until canceled.

ii. Market Orders on HNX Exchange

A buy order at the lowest selling price or a sell order at the highest buying price currently available in the market during the continuous matching session. There are three types of orders:

• Market All-or-None (MAK) order: The order can be fully or partially executed, and the remaining part of the order will be canceled immediately after matching.
• Market On Close (MOK) order: The order, if not fully executed, will be canceled immediately after entry.
• Market To Limit (MTL) order: The order can be fully or partially executed, and the remaining part of the order will be converted into a limit order.

iii. At-the-Close (ATC) Order:

• An order to buy or sell securities at the closing price. ATC orders are given priority over limit orders when matching trades.
• During the regular closing price matching session, the trade price cannot be determined if there are only ATC orders in the order book.
• The order will be automatically canceled at the end of the session if the order is not executed or not fully executed.

iv. After-Hours Matching/Puclic Limit Orders (PLO)

• A PLO order is a buy or sell order for securities at the closing price after the regular market trading session ends.
• PLO orders can only be entered into the system during the after-market trading session.
• PLO orders are matched immediately upon entry into the system if there is a corresponding pending order. The execution price is the closing price of the trading day.
• PLO orders are not allowed to be modified or cancelled.
• In cases where the execution price cannot be determined during the continuous trading session and the closing auction, PLO orders will not be accepted into the system.

B. Trading Methods:

– Periodic call auction: being performed on the basis of securities matching buy and sell orders at a specified time.

+ The price determination principle is based on achieving the highest trading volume. If multiple prices meet this condition, the price closest to the execution price of the last matching order will be selected.

+ In periodic call auction sessions, orders cannot be modified or canceled.

– Continuous auction: a trading method made on the basis of matching buy and sell orders as soon as they are entered into the trading system.

– Negotiation auction: Buyers and sellers can negotiate one-on-one deals and then notify a securities company to record the transaction results in the trading system. Alternatively, buyers or sellers can engage a securities company to find a counterparty for a reciprocal agreement.

* Note: On the first trading day of newly listed/registered securities or the first trading day after a stock has not been traded for 25 consecutive sessions, negotiated trading orders are not executed until a reference price is established based on the results of continuous matching.

3. Matching Principles:

– Price Priority: Orders with better prices (higher buy orders, lower sell orders) are given priority for execution.

– Time Priority:

• Buy or sell orders with the same price are executed in the order of their entry into the system.
• In the continuous matching session, if buy and sell orders meet the price condition (Buy Price ≥ Sell Price), the matching price is the price of the order entered into the system first.

4. Trading Units and Price Quotations

A. Trading Units:

– The trading unit (even lot) for matched trading is 100 shares, fund certificates.
– Negotiated trading volume: from 5,000 shares for HNX, ETF fund certificates; no trading unit specified.

– Odd lot trading (from 1 to 99 shares, fund certificates or covered warrants) can be executed through continuous matching or negotiated trading.
Odd lot trading of shares, fund certificates, and covered warrants newly listed or resumed trading after being suspended for more than 25 consecutive trading days cannot be entered into the trading system until a closing price is established.
– The trading unit for bonds is 1.

B. Price Quotations:

Trading Method	Stock (Listed)	Exchange-traded Funds (Listed)	UpCom Exchange
Matched trading	100 VND	1 VND	100 VND
Negotiated Deals	1 VND	1 VND	100 VND

– The tick size for corporate bonds trading is 1 VND.
5. Reference Price and Price Fluctuation Range

A. Reference Price:
i. For listed securities:

– The reference price for stocks and ETF fund certificates is the closing price of the most recent trading day (the last matched price in the previous trading day).

– The determination of the reference price for newly listed stocks and ETF fund certificates on the first trading day is proposed by the listing organization, fund management company, and listing advisory organization (if applicable). If, within 3 consecutive trading days from the first trading day, the price for the next trading day cannot be determined as the reference price, the listing organization, fund management company, and listing advisory organization (if applicable) must reassess the reference price.

– In the case of stocks and ETF fund certificates entitled to dividends and/or accompanying rights, the reference price on ex-dividend trading day is determined by taking the closing price of the most recent trading day adjusted for the received dividend value or the value of the accompanying rights.

– The reference price will not be adjusted in cases where a company issues convertible bonds or additional shares at a higher issuance price than the average price of the consecutive trading days prior to the ex-dividend date (after adjusting for other rights if applicable).

– In the case of securities suspended from trading for 25 consecutive sessions, upon resumption of trading, the reference price will be decided by HNX after approval by SSC.

ii. For securities on the Upcom exchange: the weighted average price of even-lot trading executed through continuous matching on the most recent continuous matching trading day.

B. Price Fluctuation Range:

– The price fluctuation range for stocks/ETF fund certificates during a trading day for listed securities is ± 10%, and on the Upcom exchange it is ± 15% (compared to the reference price).

– The price fluctuation range is ± 30% compared to the reference price, applied on the first trading day of newly listed stocks/ETF fund certificates, the first trading day after suspension for stocks that were suspended from trading for 25 days, and for cases of dividend payment or bonus issuance in fund certificates for existing shareholders, business separation in listed companies.
– For the Upcom exchange: the price fluctuation range is ± 40% compared to the reference price, applied on the first trading day after suspension for stocks that were suspended from trading for 25 days, and for cases of dividend payment or bonus issuance in fund certificates for existing shareholders, or dividend payment in cash at a value higher than or equal to the weighted average price of the shares on the trading day preceding the ex-dividend date.

– Ceiling/Floor Price:

• Ceiling Price = Reference Price x (100% + Fluctuation Range)
• Floor Price = Reference Price x (100% – Fluctuation Range)

For stocks with a ceiling/floor price after adjusting the price fluctuation range by ± 10% (or ± 15% for Upcom), but the ceiling/floor price remains equal to the reference price, the adjustment will be as follows:

• Adjusted Ceiling Price = Reference Price + Minimum Price Increment
• Adjusted Floor Price = Reference Price – Minimum Price Increment

In the case where the reference price is 100 VND:

• Adjusted Ceiling Price = Reference Price + Minimum Price Increment
• Adjusted Floor Price = Reference Price

6. Placing Trading Orders:

– It is allowed to simultaneously place both buy and sell orders for the same type of security during continuous matching sessions. (Note: Buy and sell orders of the same type do not cross-match automatically)
– It is not permitted to place buy and sell orders for the same type of security simultaneously within the same regular matching session, except for orders that have been entered into the securities trading system in the previous trading session, remain unmatched but are still valid.

7. Canceling and modifying matched trading orders:

– Only unmatched orders or partially unmatched orders during continuous matching trading can be canceled or modified.

– The priority order of the order on the exchange will be maintained if the modification only reduces the order quantity.

– The priority order is calculated from the time the modification order is entered into the system for cases of increasing order quantity and/or modifying the price.

8. Canceling and modifying negotiated trading orders:

– Orders can only be canceled or modified if they have not been confirmed.

– In case of incorrect order entry by the Securities Company’s representative, the order can only be modified with the approval of HNX and the investor.

9. Special transactions:

– Transactions involving the purchase and sale of mutual fund shares, market-making transactions by market makers must adhere to the specific regulations outlined in Circular 120/2020/TT-BTC issued by the Ministry of Finance.

– Transactions carried out by major shareholders, internal shareholders, and related persons must comply with the specific provisions of the Securities Law and Circular 96/2020/TT-BTC issued by the Ministry of Finance.