New stock market pre-open session rules from today: What changes for you?

After making changes to the closing session methodology, the National Stock Exchange (NSE) is now set to revise its order-entry rules for the equity market’s pre-open session from September 7. While the overall 15-minute pre-open period will remain unchanged, the rules governing when traders can place markets and limit orders will change.The revised arrangement makes the pre-open process more similar to the auction mechanism followed during the Closing Auction Session (CAS). NSE said the objective is to bring the mechanism used for determining the market opening closer to the framework already followed for the closing auction.The pre-open session will continue to operate between 9 AM and 9:15 AM. However, the order-entry period from 9 AM to 9:10 AM will now be divided into two five-minute windows.Between 9 AM and 9:05 AM, traders will be allowed to submit, modify or cancel both market and limit orders.