Description

NSE updates block trading parameters with minimum order size increased to Rs. 25 Crores and price range expanded to ±3%, effective December 08, 2025.

Summary

NSE has revised the block trading session parameters following SEBI circular SEBI/HO/MRD/POD-III/CIR/P/2025/134 dated October 08, 2025. The changes include a substantial increase in minimum order size from Rs. 10 Crores to Rs. 25 Crores and expansion of price range from ±1% to ±3% of reference price. These modifications will be effective from December 08, 2025.

Key Points

  • Minimum order size increased from Rs. 10 Crores to Rs. 25 Crores (150% increase)
  • Price range expanded from ±1% to ±3% of applicable reference price
  • Price range subject to surveillance measures and applicable price bands in normal market
  • Price range cannot exceed the day’s applicable price range for the security
  • For securities with 2% day price band, block deal range remains at ±2% (not increased to ±3%)
  • For T0 parent series with dynamic ±1% band, TL series block deal range remains at ±1%
  • Changes applicable to Capital Market Segment block trading window

Regulatory Changes

Order Size Parameter

Previous: Minimum order size of Rs. 10 Crores Revised: Minimum order size of Rs. 25 Crores

Price Range Parameter

Previous: ±1% of applicable reference price Revised: ±3% of applicable reference price, with important caveats:

  • Subject to surveillance measures applicable in normal market
  • Cannot exceed the day’s applicable price range
  • If normal market price band is 2%, block deal range remains at ±2%
  • For T0 parent series with ±1% dynamic band, TL series block deal range remains at ±1%

These changes are in partial modification to Chapter 1.7 Block Trading Session in Capital Market Consolidated Circular number 67774 dated April 30, 2025.

Compliance Requirements

For All NSE Members:

  • Update trading systems to accommodate new parameters before December 08, 2025
  • Load updated security files in trading application before effective date
  • Download security.gz/nnf_security.gz/NSE_CM_security_ddmmyyyy.csv.gz from common/NTNEAT directory on Extranet server
  • Alternatively, download CM-MII-Security File (.gz) from NSE website at https://www.nseindia.com/all-reports
  • Ensure block deal orders meet the new Rs. 25 Crores minimum threshold
  • Configure systems to apply appropriate price range limits based on security-specific bands
  • Participate in mock trading session to test updated parameters

Testing Requirements:

  • Mock trading session scheduled for December 06, 2025
  • Members should test the updated parameters during this session

Important Dates

  • November 20, 2025: Circular issued (Ref. No: 160/2025)
  • December 06, 2025: Mock trading session for testing updated parameters
  • December 08, 2025: Changes go live and become effective in production environment

Impact Assessment

Market Impact:

High Impact on Block Trading Activity:

  • 150% increase in minimum order size may reduce the number of eligible block trades
  • Higher threshold may consolidate block trading to larger institutional participants
  • Smaller institutional trades (Rs. 10-25 Crores) will need to use regular market windows

Operational Impact:

Moderate to High:

  • Trading members must update systems and security files
  • Price range expansion from ±1% to ±3% provides more flexibility for price discovery
  • Complex price band logic requires careful system configuration (security-specific bands)
  • Systems must handle conditional price ranges based on normal market bands

Liquidity Impact:

Mixed:

  • Wider price range (±3%) may improve execution probability for large orders
  • Higher minimum size may reduce overall block trading volume
  • May push some trades back to normal market hours

Compliance Impact:

Moderate:

  • Members need to ensure proper testing during mock session
  • Security file updates are mandatory for smooth operations
  • Failure to update could result in order rejections

Strategic Considerations:

  • Institutional investors planning block trades between Rs. 10-25 Crores need alternative execution strategies
  • Larger price bands may reduce market impact for trades above Rs. 25 Crores
  • Trading desks should review block trading strategies and thresholds

Impact Justification

Significant changes to block trading framework affecting minimum order size (2.5x increase) and price range flexibility, impacting institutional and large-value traders