Description
BSE applies Short Term Additional Surveillance Measure (ST-ASM) to select securities under Stage I (50% margin) and Stage II (100% margin), effective April 20, 2026, for open positions as on April 17, 2026 and new positions thereafter.
Summary
BSE has notified the applicability of the Short Term Additional Surveillance Measure (ST-ASM) framework to a set of securities listed in Annexure I, effective April 20, 2026. Securities have been categorised under Stage I and Stage II based on their satisfaction of prescribed surveillance criteria. Both stages involve heightened margin requirements, with Stage II mandating the maximum permissible margin of 100%.
Key Points
- Securities identified under ST-ASM Stage I will attract a margin of 50% or the existing applicable margin, whichever is higher, subject to a maximum cap of 100%.
- Securities identified under ST-ASM Stage II will attract a margin of 100% or the existing applicable margin, whichever is higher, subject to a maximum cap of 100%.
- Both stages are effective from April 20, 2026 and apply to all open positions as on April 17, 2026 and all new positions created from April 20, 2026.
- The ASM framework operates in conjunction with all other prevailing surveillance measures imposed by the Exchanges.
- Shortlisting under ASM is purely a market surveillance action and should not be construed as an adverse action against the concerned company or entity.
- Upon exit from the ASM framework, the price band of the scrip will be reinstated to the level applicable before its inclusion, unless the scrip is part of another surveillance measure.
Regulatory Changes
This notice is issued further to prior Exchange notices revising the ASM framework:
- Notice 20240920-71 dated September 20, 2024
- Notice 20181027-1 dated October 27, 2018
- Notice 20190719-33 dated July 19, 2019
- Notice 20201204-56 dated December 04, 2020
- Notice 20230925-49 dated September 25, 2023
- Notice 20240920-63 dated September 20, 2024
The current notice applies the revised ASM framework provisions to a fresh set of securities as per the attached Annexure I.
Compliance Requirements
- Trading Members / Brokers: Must ensure that the revised margin requirements (Stage I: ≥50%, Stage II: 100%) are applied to all client positions in affected securities from April 20, 2026, including existing open positions as of April 17, 2026.
- Market Participants: Must note that ASM applies alongside any other existing surveillance measures; the more restrictive price band/margin will prevail.
- Members with clarifications may contact BSE Surveillance at bse.surv@bseindia.com.
Important Dates
| Event | Date |
|---|---|
| Notice Date | April 16, 2026 |
| Reference Date for Open Positions | April 17, 2026 |
| Effective Date for Revised Margins | April 20, 2026 |
Impact Assessment
The imposition of ST-ASM Stage I and Stage II significantly increases the cost of trading in affected securities by mandating higher margins. Stage II securities, subject to 100% margin, face near-complete restriction on leveraged trading, substantially reducing liquidity. This is a targeted surveillance action to curb abnormal price movements in identified scrips. Market participants holding or planning positions in the listed securities must ensure adequate funds are available to meet the enhanced margin obligations. The price band reinstatement provision upon exit provides a defined path back to normal trading conditions, subject to no other overlapping surveillance measure.
Impact Justification
Imposition of elevated margin requirements (up to 100%) on identified securities under ST-ASM directly restricts trading activity and liquidity, with immediate market-wide implications for affected scrips from April 20, 2026.