The SET is currently reviewing trading supervision measures to ensure their implementation effectively boosts confidence among capital market participants.
This is in line with the SET’s strategic plan to create opportunities, enhance liquidity, and increase confidence under the vision of “The Trusted Gateway to Inclusive Opportunities”.
Therefore, the SET is open to hearing opinions from investors and related parties on the topic of “Improving Measures to Enhance Confidence”. From May 13-29, 2026, the essence of the measures reviewed this time can be summarized as follows
Group 1: Additional measures to improve market quality. Strengthen fairness and market efficiency in terms of structure and cost
.1. Reduce the tick size for securities priced from 5-50 baht per share to reduce the price differential. This will result in a reduction in trading costs for all groups of investors and increase liquidity in the market.2
. In the event that an account has more than 100 times OTR and more than 50 orders per minute (active minute), such account will be charged an additional fee at the rate of 0.15 baht per transaction (15 satang) only for the amount exceeding 30,000 transactions/day
.Group 2 Measures to reduce abnormal fluctuations in securities prices
3. Uptick Rule for Short Selling In the event that the price of a security decreases by 10% or more from the closing price of the previous day, the uptick criteria will be applied for that security on the next business day. This is to help slow down the selling force during market volatility and maintain balance while reducing the impact on liquidity and trading costs. If it is a normal condition, the criteria will be used.
4 Review securities that can be shorted by limiting short selling to highly liquid stocks.
5 Abolish the Dynamic Price Band (DPB) trading price bracket for each securities to reduce trading barriers, especially in low-liquidity stocks.
Group 3 Measures to Govern Inappropriate Trading Behavior
6. Register a high-speed trader (HFT) by switching to a post-trade trading behavior such as frequency/speed of order submission. Or there is a channel for sending orders for specific investors (Dedicated API) so that supervision is based on facts and can monitor trading behavior appropriately.
7. Lifting restrictions on securities that HFT can trade This is due to the revision of the rules of securities that can beShort selling can only cover highly liquid securities. In addition, HFT will be supervised based on the actual trading behavior.
8. Cancel Minimum Resting Time (MRT) is because it was found that the number of transactions triggered under this measure is very small, which does not effectively supervise trading behavior and will reduce the systemic burden and is not in line with the guidelines of foreign stock exchanges. In addition, The SET already has other mechanisms to supervise inappropriate behavior, such as the use of AI to help analyze and detect abnormal trading behavior, and measures to collect extra charges on accounts with high OTR behavior, etc
The SET has published a detailed public opinion document on the SET website https://www.set.or.th/th/rules-regulations/market-consultation entitled “Improvement of Measures to Enhance Confidence”. Those involved can submit their comments at https://forms.microsoft.com/r/EFQF82bt4c from 13-29 May 2026.
Source : Stock Exchange Open to listening to opinions on improving measures to raise confidence.
