The National Stock Exchange (NSE) on June 19, 2026, issued Mock trading on Saturday, June 20, 2026 – Testing of Trading modalities related to Introduction of Closing Auction Session (CAS).
The Exchange will conduct a mock trading session in the Capital Market (CM) segment on June 20, 2026, to test the implementation of the Closing Auction Session (CAS) and revised trading modalities. The mock will be conducted across three trading sessions spanning DR and primary sites, covering various market segments such as normal market, block deals, T+0, auction market, and CAS.
A new NEATPlus version (7.8.9) will be used exclusively for Trading Session-1 to enable CAS-related testing. For Trading Sessions 2 and 3, and live trading from June 22, 2026, members must revert to NEATPlus version (7.8.8). Members are also required to load updated master files prior to Session-1 for accurate testing.
Additionally, members must note the discontinuation of order book snapshot recovery via Solace API and migrate to TCP/IP-based recovery. The circular also mandates implementation of a new CA certificate and updated NEAT Adapter versions by July 6, 2026, with enhanced encryption features and revised network parameters. Active participation and timely system readiness are strongly advised.
[Circular No: 87/2026]
