The Additional Surveillance Measure (ASM) and Graded Surveillance Measure (GSM) are both surveillance measures used by the Indian stock exchanges to monitor and regulate the trading of certain securities. However, there are some differences between the two:

  1. Scope: The GSM framework is applicable to all listed securities, whereas the ASM framework is only applicable to specific securities that are identified as being at risk of price manipulation or other irregularities.
  2. Surveillance Levels: Under the GSM framework, securities are placed under different levels of surveillance based on their trading behavior. Under the ASM framework, specific securities are placed under more stringent surveillance and monitoring requirements.
  3. Applicable Restrictions: The GSM framework is primarily used for monitoring and surveillance purposes, while the ASM framework is used to impose additional restrictions on the trading of specific securities. For example, stock exchanges may restrict trading or increase margin requirements for securities placed under the ASM framework.

In summary, while both surveillance measures are used to maintain market integrity and ensure fair trading practices, the GSM framework is a general surveillance system applicable to all listed securities, while the ASM framework is a more specific system applicable to identified high-risk securities. Additionally, the ASM framework allows for the imposition of additional restrictions on the trading of specific securities.