Order Types

1. At-the-Opening Order (ATO)

• An order to buy or sell securities at the opening price. ATO orders have priority over limit orders when matching trades.
• The periodic matching session to determine the opening price will not determine the matching price if there are only ATO orders in the order book.
• ATO orders are entered into the trading system during the periodic matching session to determine the opening price and will be automatically canceled after the opening price is determined if the orders are not executed or not fully executed.

2. Limit Order (LO)

• A buy or sell order for securities at a specified price or better. The order is valid from the time it is entered into the trading system until the end of the trading day or until the order is canceled.

3.  Market Price Order (MP) on HSX

• A buy/sell order for securities at the lowest available selling price/highest available buying price on the market.
• When entered into the trading system, an MP buy order will be executed immediately at the lowest available selling price, and an MP sell order will be executed immediately at the highest available buying price on the market. If the volume of the MP order is not fully executed, the remaining volume will be treated as a buy order at the next higher selling price or a sell order at the next lower buying price available on the market and will continue to match.
• If the volume of the MP order remains after following this principle and cannot be further matched, the MP order will be converted into a limit buy order at a price one tick higher than the last executed price or a limit sell order at a price one tick lower than the last executed price.
• If the last executed price is the ceiling price for an MP buy order or the floor price for an MP sell order, the market order will be converted into a limit buy order at the ceiling price or a limit sell order at the floor price.
• The MP order is valid during the continuous matching session.
• The MP order will be automatically canceled if there is no opposing limit order at the time of order entry into the trading system. – An MP buy order from a foreign investor, after partial execution, will have the remaining portion automatically canceled if the securities reach the ownership limit.

4. Market Price Order on the HNX

• A buy order at the lowest available selling price or a sell order at the highest available buying price on the market during the continuous matching session. There are 03 types of orders:
• MAK order: An order that can be executed in full or in part, with the remaining portion of the order being canceled immediately after matching.
• MOK order: An order that will be canceled immediately if not fully executed upon entry into the system.
• MTL order: An order that can be executed in full or in part, with the remaining portion of the order being converted into a limit order (LO).

5. Closing Price Order (ATC)

• An ATC order is a buy or sell order for securities at the closing price. The ATC order takes priority over limit orders when matching. The periodic closing price matching session will not determine the matching price if there are only ATC orders in the order book.
• The order will automatically be canceled at the end of the session if it is not executed or not fully executed.

6. After-Hours Matching Order (PLO)

• A PLO order is a buy or sell order for securities at the closing price after the end of the periodic closing price matching session.
• PLO orders can only be entered into the system during the after-hours trading session.
• A PLO order is matched immediately upon entry into the system if there is a corresponding order waiting. The execution price is the closing price of the trading day.
• PLO orders cannot be modified or canceled.
• If the continuous matching session and the periodic closing price matching session do not determine an execution price, PLO orders will not be entered into the system.