NSE has announced the applicability of Short-Term Additional Surveillance Measure (ST-ASM) for select securities effective May 19-20, 2026. Three securities — De Neers Tools Limited (DENEERS), Noida Toll Bridge Company Limited (NOIDATOLL), and Sakar Healthcare Limited (SAKAR) — have been included under ST-ASM Stage I. No securities have been added to ST-ASM Stage II. Two securities have been excluded from the ASM framework.

Key Points

• 3 securities added to ST-ASM Stage I: DENEERS, NOIDATOLL, SAKAR
• ST-ASM Stage I margin: 50% or existing margin, whichever is higher (capped at 100%)
• ST-ASM Stage II margin: 100% or existing margin, whichever is higher (capped at 100%) — no new additions this cycle
• No securities moved between Stage I and Stage II
• 2 securities excluded from ASM framework: APCOTEXIND (Apcotex Industries Limited) and ASPIRE
• Shortlisting is purely for market surveillance purposes and should not be construed as adverse action against the companies

Regulatory Changes

This circular is issued further to prior ASM circulars: NSE/SURV/39265 (Oct 27, 2018), NSE/SURV/46557 (Dec 4, 2020), NSE/SURV/52144 (Apr 28, 2022), NSE/SURV/58558 (Sep 25, 2023), and NSE/SURV/64066 (Sep 20, 2024). The ST-ASM framework operates in conjunction with all other prevailing surveillance measures imposed by the exchanges.

Compliance Requirements

• NSE members must apply the enhanced margin requirements for ST-ASM Stage I securities (minimum 50%, capped at 100%) on all open positions as on May 19, 2026 and new positions created from May 20, 2026
• Members must ensure compliance with ST-ASM Stage II margin of 100% for any applicable securities
• ASM framework applies alongside all other existing surveillance measures
• For queries, members may contact surveillance@nse.co.in

Important Dates

• May 18, 2026: Circular issued
• May 19, 2026: Effective date for inclusion/exclusion of securities in ASM lists; reference date for open positions
• May 20, 2026: Enhanced margin requirements become applicable on open positions (as of May 19) and all new positions

Impact Assessment

Traders and investors holding or planning to take positions in DENEERS, NOIDATOLL, and SAKAR will face increased margin requirements of at least 50% from May 20, 2026, significantly raising the cost of trading these securities. This is likely to reduce liquidity and may cause volatility in these counters. Conversely, traders in APCOTEXIND and ASPIRE benefit from their exclusion from the ASM framework, potentially improving liquidity and reducing margin burden for those stocks.