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Market Surveillance
SET is responsible for monitoring and supervising securities and derivatives trading to
enhance market transparency and market integrity. SET has enforced measures to prevent
irregular or unfair trading transactions, including insider trading, market manipulation and
misstatements.
To enhance its effectiveness and efficiency, SET uses a
real-time securities trading supervision system, the Warning
Abnormal Trading & Catching Hostile System (WATCHs).
Should there be any irregular trading transaction which
can be considered as an offence, SET may:
1. Contact the listed company in question, asking it to
disclose the material information which may have resulted
an irregular trading transaction.
2. Notify member companies likely to submit a trading
transaction which is possibly related to stock price
manipulation.
3. Implement trading alert and turnover list measures
as follows:
Investors are required to use Cash Balance
accounts in trading only.
Investors are required to use Cash Balance
accounts in trading only and the value of
securities traded is excluded from credit
line calculation.
Investors are required to use Cash Balance
accounts in trading only and the value of
securities traded is excluded from credit
line calculation. Also, the investors are
prohibited from offsetting the trading value
of buy amount and sell amount of a certain
security on a given day (Net settlement).
If a security’s trading pattern has changed significantly from its normal pattern or become highly concentrated in a
particular individual or group of individuals without apparent reason, SET may consider to temporarily halt (H) its trade.
Trading alert
Levels
of measures
Measures
Cash balance
Level 3
(TA3)
Prohibited from
Net settlement
Excluded
from credit limit
Level 2
(TA2)
Level 1
(TA1)