Description

NSE revises strike scheme parameters including step values and number of strikes for stock options, effective December 31, 2025.

Summary

NSE has revised the strike scheme for stock options, updating step values and number of strikes available for trading. The changes reference Chapter 1.10 of the F&O Consolidated Circular (NSE/FAOP/67775 dated April 30, 2025) and will be implemented from December 31, 2025. Members must load updated contract files before trading commences on the effective date.

Key Points

  • Revised strike schemes apply to multiple stock options including narrow and wide range categories
  • Strike schemes differentiate between Near, Mid, and Far month contracts
  • Step values vary by stock and range from 2.5 to 200 points depending on the underlying security
  • Number of strikes available varies by contract month (Near typically has most strikes, Far has least)
  • Reserve strikes are also specified for each stock across different contract months
  • Updated contract.gz file must be loaded from /faoftp/faocommon directory on extranet server

Regulatory Changes

Revision of strike scheme parameters including:

  • Step values for narrow range: Different values for Near, Mid, and Far months
  • Step values for wide range: Typically double the narrow range values
  • Strike scheme counts: Number of strikes available for trading varies by month
  • Reserve strikes: Additional strikes kept in reserve for each contract month

Examples from Annexure 1:

  • 360ONE: Narrow range step values 20/20/40, Wide range 40/40/80
  • APOLLOHOSP: Narrow range step values 50/50/100, Wide range 100/100/200
  • ASHOKLEY: Narrow range step values 2.5/2.5/5, Wide range 5/5/10

Compliance Requirements

  • Trading members must load the updated contract.gz file in their trading applications before December 31, 2025
  • File to be obtained from /faoftp/faocommon directory on NSE extranet server
  • Members must ensure systems are updated to reflect new strike schemes for affected stocks
  • Reference to master circular NSE/FAOP/67775 dated April 30, 2025 for detailed framework

Important Dates

  • Circular Date: December 17, 2025
  • Effective Date: December 31, 2025 (new strike schemes become applicable for trading)
  • System Update Deadline: Before trading on December 31, 2025

Impact Assessment

This revision affects F&O market participants trading stock options in the listed securities. The changes impact:

Trading Strategy: Modified strike intervals may require adjustments to options strategies and hedge positions

Liquidity: Changes in number of available strikes could affect liquidity distribution across different strike prices

Risk Management: Updated strike schemes require recalibration of risk management systems and position monitoring tools

Market Participants: Primary impact on options traders, market makers, proprietary trading desks, and institutional participants using stock options for hedging or speculation

Operational Impact: Members need to ensure technical systems are updated before the effective date to avoid trading disruptions

Impact Justification

Technical update affecting F&O traders dealing with stock options. Changes strike intervals and availability which impacts trading strategies but doesn't fundamentally alter market structure.