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The Stock Exchange of Thailand (SET) has revamped its securities trading rules to suit current business conditions and support new trading systems that will be launched in the first quarter of this year.
SET president Pakorn Peetathawatchai said the revised rules would be more consistent with international practices while also boosting convenience and expanding investment opportunities for investors.
For example, the criteria for determining opening and closing prices (equilibrium price) will be adjusted to be in accordance with international practice. After the adjustment, the opening and closing prices may be outside the highest price range (ceiling) and the lowest price range (floor), previously defined to be within the price range not exceeding ceiling and floor.
The regulator will also put a P (pause) sign in the case of trading regulation measures applied to securities whose trading conditions deviate from normal market conditions, instead of currently using the SP (suspension) mark to make it clear to investors.
The SET has also added an "overnight order" type, said Mr Pakorn. Investors can now place good till cancel (GTC) or good till date (GTD) orders, and those will remain in the trading system of the SET until cancelled or until the date specified by the sender of the order. But this will not exceed 30 days.
The criteria for the floor and ceiling of foreign stocks has been adjusted to be no more than 60% above or below the reference price for all trading methods. Nowadays, foreign stocks are traded using the trade report method for large transactions which are 1 million units or have a trading value of 3 million baht or more. The previous criteria of the price not being 30% above or below the reference price was inconsistent with foreign stock trading by other trading methods, Mr Pakorn explained.
Furthermore, the SET has cancelled the trading of derivatives warrants (DW), also known as the "odd lot", which trade DWs below 100 units, he said, noting that the current DW trading value is very small.
To support emergencies or prevent possible damage to trade as a whole, orders can also be cancelled when there is a system failure. The revised rules will take effect with the launch of the new trading system by the first quarter of this year, Mr Pakorn added.