The Additional Surveillance Measures (ASM) initiative is part of SEBI and the Exchanges' efforts to enhance market integrity and protect investors' interests. This initiative introduces extra monitoring and margin requirements for certain securities that exhibit high volatility or risk.

Types of Additional Surveillance Measures:

1. Long-Term Additional Surveillance Measures: Applied to securities that require prolonged monitoring due to consistent volatility or risk factors.
2. Short-Term Additional Surveillance Measures: Applied to securities that show short-term spikes in volatility or risk, requiring immediate but temporary additional surveillance.

Surveillance Actions:

Securities under ASM are monitored based on pre-determined criteria. If these criteria are met, the securities may be moved to the Trade for Trade segment, where 100% of the traded value is required as margin, and no intraday leverage is provided.

Key Points to Note:

1. Margin Requirements:
   • 100% Margin Blocked: No intraday leverage is provided for securities under ASM. This means MIS, CO, and NRML product types are not allowed.
   • Full Margin Orders: Orders can only be placed under the CNC (Cash and Carry) product type, requiring full margin upfront.
2. Pledging Restrictions:  Stocks under ASM cannot be pledged. If a stock that you have pledged moves under ASM, you will no longer receive collateral margins for that stock.
3. Corporate Actions:  Corporate actions such as bonuses, dividends, and stock splits are not impacted by a stock being under ASM. Shareholders will still receive these benefits.
4. Impact on Collateral:  If a pledged stock is moved to ASM, the collateral value will decrease by the value of collateral received against that stock. You can choose to un-pledge the stock or keep it pledged without receiving collateral until it is moved out of ASM.

For more details, refer to the NSE FAQ on ASM.