Description

BSE introduces pre-open session in equity derivatives with technical specifications for order management and market data communication.

Summary

BSE has issued technical specifications for the implementation of pre-open session in the equity derivatives segment. The circular provides detailed messaging format requirements for ETI API and market data communication streams (EOBI, EMDI, MDI, NFCAST) during pre-open sessions.

Key Points

  • ETI messaging format for order management remains unchanged during pre-open session
  • All existing order-related actions (addition, modification, deletion) can be performed using current ETI messages
  • No auction-exclusive messages required for equity derivatives pre-open session
  • Market data dissemination continues through four distinct streams with specific field values for auction sessions
  • Different SecurityTradingStatus values for various pre-open phases: 4 (order entry), 5 (freeze), 1 (matching end), 3 (continuous)

Regulatory Changes

  • Introduction of pre-open session in equity derivatives segment
  • Specific template IDs and field values defined for different market data streams
  • New auction clearing price message (Template ID: 13501) during pre-open session
  • Enhanced market data communication with auction-specific enum values

Compliance Requirements

  • Members must review complete messaging format documents to identify all auction-related specifications
  • Trading systems need to handle new SecurityTradingStatus and SecurityMassTradingStatus field values
  • Market data consumers must accommodate auction clearing price messages and new MDEntryType enum values (6, 12, 13)
  • Applications may require updates to process pre-open session states correctly

Important Dates

No specific implementation dates mentioned in the circular.

Impact Assessment

Medium impact on equity derivatives trading infrastructure. While existing order management remains unchanged, market data systems and trading applications will need updates to handle pre-open session states and auction-related messages. The change primarily affects technical systems rather than trading procedures.

Impact Justification

Technical implementation affecting equity derivatives trading operations and market data systems