SGX Pre-Open And Pre-Close Routines
The Pre-Open and Pre-Close Routines
As an extension to the regular trading session (9.00 am – 5.00 pm) for the stock market, the Singapore Exchange Securities Trading Limited (SGX-ST) introduced a Pre-Open and a Pre-Close Routine on 21st August 2000. It is aimed at increasing efficiency and transparency of the marketplace, so as to facilitate smooth price movements during the opening and closing sessions of trading.
The Pre-Open Routine is a 30 minutes auction session (consisting of a Pre-Open Period and a Non-Cancel Period), which is conducted prior to the commencement of the regular trading session at 9.00 am. As for the Pre-Close Routine, it runs for 6 minutes. Likewise, it will also have a Pre-Close Period and a Non-Cancel Period.
Pre-Open Routine
Pre-Open Period (8.30 am – 8.59 am):
Buy and sell orders are keyed into the SGX trading terminals, and the orders can be amended or withdrawn. However the orders placed are not matched yet.
Non-Cancel Period (8.59 am – 9.00 am):
No further entries, amendments or withdrawal of orders are allowed. Orders that can be matched are executed based on a single “opening” price computed by the SGX trading system. All unmatched orders will flow into the regular trading session.
Adjust Phase
Lunch Break Hours (12.30 pm – 1.59 pm):
Orders can be entered, reduced in quantity or withdrawn. No matching of orders is carried out.
Adjust Phase Non-Cancel Period (1.59 pm – 2.00 pm):
Orders cannot be entered, amended nor withdrawn. Orders that can be matched will be matched at a single price computed based on an algorithm set by SGX-ST. Unmatched orders are carried forward into the afternoon trading session.
Pre-Close Routine
Pre-Close Period (5.00 pm – 5.05 pm):
Buy and sell orders are keyed into the SGX trading terminals, and the orders can be amended or withdrawn. However the orders placed are not matched yet.
Non-Cancel Period (5.05 pm – 5.06 pm):
No further entries, amendments or withdrawal of orders are allowed. Orders that can be matched are executed based on a single “closing” price computed by the SGX trading system (similar to the formulae used for the Pre-Open Routine). All unmatched orders are discarded.
~ Source: SIAS
