What is the difference between ASM and ESM?

ESM applies to companies with a market capitalisation under ₹1,000 crore whose price has varied far more than usual, in two stages with trade-for-trade settlement and a tight price band. ASM looks at price and volume variation together with how concentrated the trading is, in a long-term framework (four stages) and a short-term one (two stages), mainly through higher margins and, in the long term, lower price bands.

The Graded Surveillance Measure applies to securities whose price is not in line with the company's financial health and fundamentals, such as earnings, book value, net worth and P/E. Its graded stages add measures such as trade-for-trade settlement with a price band of 5% or lower, an additional surveillance deposit and, in later stages, trading only once a week.

Can a stock be under more than one surveillance measure?

Yes. ASM works in addition to the other actions on a stock, and where several apply the exchanges apply the stricter one. Securities already under GSM are left out of ASM shortlisting.

ASM vs ESM vs GSM: how the surveillance measures differ

Last reviewed 13 October 2026 · by Rachid Asen

NSE and BSE run several surveillance frameworks side by side. ESM, ASM and GSM look at different signals and use different measures, and a stock can be under more than one. This page compares them at a high level; the exchange pages linked under Sources have the full rules.

Side by side

Measure	What puts a stock there	Stages	Typical measures	Review
ESM (Enhanced Surveillance Measure)	Unusual price variation in companies with a market capitalisation under ₹1,000 crore; no F&O stocks	Stage 1, Stage 2	Trade-for-trade settlement, a tight price band and 100% margin; Stage 2 trades only in periodic call auctions	Weekly; at least 90 calendar days in the framework
ASM (Additional Surveillance Measure)	Price and volume variation together with concentrated trading, and for some criteria market capitalisation, delivery or P/E	Long-term I–IV; short-term I–II	Higher margins; long-term Stages II–IV lower the price band, and Stage IV adds gross settlement with a 5% band	Long-term: weekly, after 90 calendar days, one stage at a time. Short-term: after 5 or 15 trading days
GSM (Graded Surveillance Measure)	A price not in line with the company's financial health and fundamentals (earnings, book value, fixed assets, net worth, P/E, market capitalisation)	Graded stages (see NSE's GSM page)	Trade-for-trade settlement with a price band of 5% or lower, an additional surveillance deposit, and in later stages trading only once a week	Periodic (quarterly, per NSE's GSM page)

Measures as published in NSE's FAQ on ASM (last updated 20 September 2024), checked on 13 October 2026. The exchanges change them by circular; the current circular applies.

When measures overlap

ASM works in addition to the other actions on a stock: where a stock attracts several, the exchanges apply the stricter action. Securities already under GSM or in trade-for-trade settlement are left out of ASM shortlisting. None of these measures is an adverse action against the company.

ESM: What is ESM?, Stage 1, Stage 2, exit rules and the ESM stocks list.
ASM: What is ASM?, long-term ASM and short-term ASM.

Frequently asked questions

What is the difference between ASM and ESM?: ESM applies to companies with a market capitalisation under ₹1,000 crore whose price has varied far more than usual, in two stages with trade-for-trade settlement and a tight price band. ASM looks at price and volume variation together with how concentrated the trading is, in a long-term framework (four stages) and a short-term one (two stages), mainly through higher margins and, in the long term, lower price bands.
What is GSM?: The Graded Surveillance Measure applies to securities whose price is not in line with the company's financial health and fundamentals, such as earnings, book value, net worth and P/E. Its graded stages add measures such as trade-for-trade settlement with a price band of 5% or lower, an additional surveillance deposit and, in later stages, trading only once a week.
Can a stock be under more than one surveillance measure?: Yes. ASM works in addition to the other actions on a stock, and where several apply the exchanges apply the stricter one. Securities already under GSM are left out of ASM shortlisting.

Sources

NSE: FAQs – Additional Surveillance Measure (ASM), last updated 20 September 2024: shortlisting criteria, long-term stages I–IV, short-term stages I–II, review and exit. It cites circulars NSE/SURV/52090 (22 April 2022, long-term ASM) and NSE/SURV/52144 (28 April 2022, short-term ASM).
NSE: Additional Surveillance Measure (ASM): the framework's parameters and NSE's list of shortlisted securities.
BSE: Additional Surveillance Measure (ASM) and BSE: FAQs on ASM: BSE's circulars, its long-term and short-term ASM lists, and its daily “Applicability of Additional Surveillance Measure” notices.
NSE: Graded Surveillance Measure (GSM): what GSM covers, its stages and review.
NSE: FAQs – Enhanced Surveillance Measure (ESM), version 1.1, 25 July 2025 (circular NSE/SURV/69315): ESM eligibility, stages and exit.

Exchange circulars change. Where this page and the current circular differ, the circular applies.

More ESM and ASM guides

What is ESM?Who can be put under ESM on NSE and BSE, what changes for the stock, and who decides.
ESM Stage 1The price-variation tests that put a stock in Stage 1 and the trading limits that follow.
ESM Stage 2When a Stage 1 stock moves to the stricter Stage 2, and when it can move back.
ESM exit rulesThe weekly review, the 90-day minimum and why a Stage 2 stock exits in two steps.
What is ASM?What ASM is, its long-term and short-term frameworks, the typical measures and who decides.
Long-term ASM (LT-ASM)The four long-term stages, what each one changes, and the 90-day stage-wise exit.
Short-term ASM (ST-ASM)The two short-term stages, their margins and the 5 or 15 trading-day review.

Not investment advice. This page explains the exchanges' published rules for education only. It does not recommend buying, selling or holding any security. Inclusion, stage changes and exit are decided solely by NSE and BSE.

Rachid Asen's personal research and personal thoughts. It is not investment advice.