If you have seen “IDSS” next to a counter in your trading app or in a Bursa announcement, it refers to short selling within a single trading day. It was opened to all investors in April 2018, so retail investors can use it, not only institutions. This guide covers what IDSS means, the rules that apply, how a trade works, and the risks to understand before you try it.
What Does IDSS Mean on Bursa Malaysia?
IDSS is Intraday Short Selling. A normal trade is buy first, sell later. IDSS reverses the order: you sell first and buy back later the same day. You do this when you expect the price to fall during the session.
On Bursa the acronym only means Intraday Short Selling. If you saw “IDSS” in a banking context, it refers to something unrelated.
The Key IDSS Rules
| Rule | What it means for you |
|---|---|
| Approved Securities only | You can only short counters on Bursa’s Approved Securities list. Bursa reviews the list periodically, so a counter can be added or removed. |
| Close the same day | Every IDSS sell must be matched by a buy of the same counter on the market, on the same trading day. You cannot carry an IDSS position overnight. |
| At-tick rule | Since 2022, IDSS sell orders must be executed at the best current asking price or higher. You cannot short by hitting the bid at a lower price. |
| 15% suspension | If a counter falls by more than 15% (or 15 sen) from its reference price, Bursa suspends IDSS on that counter for the rest of the day. Normal trading continues, and IDSS reactivates the next day if the counter is still eligible. |
| Short-position limit | Bursa also caps total short selling in each counter. IDSS on that counter is suspended once the limit is reached. |
How to Know If a Counter Is IDSS-Eligible
Check Bursa Malaysia’s latest Approved Securities list, or ask your remisier to confirm before you trade. Some trading platforms also mark eligible counters. Only established, liquid counters make the list. One of the criteria is a market capitalisation of at least RM200 million over the preceding three months. Listed ETFs are also approved, except inverse ETFs.
Because the list changes, check it again before each trade instead of relying on an old list.
How an IDSS Trade Works (Example)
Say counter ABC is trading at RM1.70 and you expect it to weaken during the day.
- Open the position: place an IDSS Sell for 1,000 shares at RM1.70. Your order goes in at the best asking price or higher, as the at-tick rule requires.
- Watch the position: you now owe 1,000 shares that you must buy back before the close.
- Close the position: place an IDSS Buy for 1,000 shares.
If the price falls and you buy back at RM1.60, you gain 10 sen per share, or RM100 before brokerage, clearing fees and stamp duty on both legs.
If the price rises and you buy back at RM1.80, you lose 10 sen per share, or RM100 plus costs. A buyer can lose at most what they paid, but a short seller’s loss grows as long as the price keeps rising.
What Happens If You Don’t Close an IDSS Position?
Failing to buy back by the end of the day breaches the IDSS rules. The shortfall must still be covered, at whatever the price is by then, and the breach can bring regulatory penalties. Do not treat the closing minutes as your plan to exit. Close early enough that a fast-moving or suspended counter cannot trap you.
IDSS vs RSS: What’s the Difference?
| IDSS (Intraday Short Selling) | RSS (Regulated Short Selling) | |
|---|---|---|
| Holding period | Same day only | Can be held overnight |
| Borrowing shares | No borrowing needed if closed the same day | Shares must be borrowed first |
| Eligible counters | Bursa’s Approved Securities | Bursa’s Approved Securities |
| Typical user | Active intraday traders | Investors and hedgers taking a view over days or weeks |
Risks to Understand Before Using IDSS
- Losses have no fixed ceiling. A sharp rally or a positive announcement can move the price against you quickly.
- Costs add up. Every round trip pays brokerage, clearing fees and stamp duty on both legs, so a small price move may not cover them.
- Liquidity can disappear. In a fast market you may not be able to buy back at the price you want.
- Same-day pressure. The position must be closed whatever the price is, which removes the option of waiting.
How to Start Using IDSS
IDSS is not switched on automatically. Your broker must enable it on your account first. You will normally sign a securities borrowing and lending agreement, a risk disclosure statement and a short declaration that you understand the rules.
If you already trade with M+: ask your remisier to enable IDSS on your account and send you the forms.
If you are opening a new account:
- Download the M+ Global app.
- Sign up and choose the Malaysia market.
- Enter invitation code UBZQ.
- Once your account is ready, I will send you the IDSS forms to complete.
Frequently Asked Questions
What does IDSS stand for in the stock market?
IDSS stands for Intraday Short Selling: selling an approved counter you do not own and buying it back within the same trading day.
Can retail investors do IDSS in Malaysia?
Yes. Since April 2018, IDSS has been open to all investors whose broker has enabled it on their account.
Can I hold an IDSS position overnight?
No. An IDSS position must be closed with an on-market buy on the same trading day. Short selling held overnight falls under Regulated Short Selling (RSS), which requires borrowed shares.
Why was IDSS suspended on a counter today?
Usually because the counter fell by more than 15% (or 15 sen) from its reference price, or because the short-selling limit for that counter was reached. The suspension covers IDSS only, and normal buying and selling continue.
Where is the IDSS counter list?
Bursa Malaysia publishes the Approved Securities list, and your remisier can confirm whether a counter is on it. Check the latest list, because it changes.
Key Takeaways
- IDSS means Intraday Short Selling: sell first, buy back the same day.
- Only Bursa’s Approved Securities can be shorted, and the list changes.
- Sell orders follow the at-tick rule: best asking price or higher.
- IDSS on a counter is suspended for the day after a fall of more than 15% (or 15 sen).
- Losses can exceed your expectation if the price rallies, so plan your exit and position size first.
If you want IDSS enabled on your account, or want to understand how it fits your trading before you start, message me. I’m Dexter Chia, remisier at Malacca Securities Sdn Bhd, on WhatsApp at +60169059789 or via M+ Global invitation code UBZQ.
Need Help With This?
If you are an M+ Global client and want IDSS set up on your account, message me directly and I will send you the forms.
WhatsApp: +60169059789 | M+ Global Invitation Code: UBZQ
Disclaimer: This article is for informational purposes only and does not constitute financial advice. Always do your own research before making investment decisions.
Want to invest in Bursa Malaysia or US markets? Contact Dexter Chia, an AI Driven Remisier who has 2,200+ clients at Malacca Securities Sdn Bhd (M+ Global). M+ Global Invitation Code: UBZQ | WhatsApp: +60169059789 | Why Choose Dexter?
