BSE has updated the Long Term Additional Surveillance Measure (LT-ASM) framework, imposing 100% margins on newly added securities effective April 29, 2026. Additionally, securities moving to higher LT-ASM stages will face a Lower Price Band from April 27, 2026, and certain securities will be transferred to T/XT/MT/TS trading groups. The framework is referenced under the original notice 20180321-46 and subsequent revisions through 2024.

Key Points

• 100% margins applicable from April 29, 2026 on all open positions as on April 28, 2026 and any new positions created thereafter
• Securities moving to higher stages of LT-ASM Framework effective April 27, 2026 (Annexure I, Part B)
• Lower Price Band imposed on stage-escalated securities effective April 27, 2026
• Certain securities to continue in LT-ASM but transferred to T/XT/MT/TS Group effective April 29, 2026 (Annexure I, Part D)
• Securities moving out of LT-ASM Framework effective April 27, 2026 listed in Annexure II
• Consolidated list of all securities under the framework available in Annexure III
• Shortlisting of securities is based on XBRL submissions by listed companies
• LT-ASM framework operates in conjunction with all other prevailing surveillance measures

Regulatory Changes

The circular references the revised LT-ASM framework per notices: 20180321-46 (March 21, 2018), 20181027-1 (October 27, 2018), 20201204-56 (December 4, 2020), 20240809-46 (August 9, 2024), and 20240920-63 (September 20, 2024). The current update applies the revised framework to add new securities, escalate existing ones to higher stages, and graduate certain securities out of the framework.

Compliance Requirements

• Brokers/Members: Must ensure 100% margins are collected on LT-ASM securities for open positions as of April 28, 2026 and all new positions from April 29, 2026 onwards
• Members: Must adhere to lower price bands on securities elevated to higher LT-ASM stages from April 27, 2026
• Investors/Traders: Must maintain sufficient margin to hold or create positions in affected securities
• For clarifications, members may write to bse.surv@bseindia.com

Important Dates

Impact Assessment

High impact on affected securities. The 100% margin requirement significantly increases the cost of holding or trading LT-ASM-listed securities, effectively reducing leverage and potentially dampening liquidity. The lower price band restricts downside volatility for stage-escalated securities, which may also limit price discovery. Transfer to T/XT/MT/TS groups may affect settlement cycles and trading conditions. Market participants should review the attached annexures to identify specific securities affected. The notice emphasizes that shortlisting is purely a surveillance action and should not be construed as an adverse action against the listed company.