IPOs and Re-listed scrips are traded in the Special Pre-open session only on the first day of their trading (in case of IPOs) and recommencement of trading (in case of re-listed scrips). One hour special Pre-Open session has been introduced only for IPOs & Re-listed scrips through the call auction trading mechanism on the first day of their trading (in case of IPOs) and recommencement of trading (in case of re-listed scrip). The special pre-open session will run parallel to the existing cycle of pre-open session for SENSEX/NIFTY & BSE exclusively traded stocks followed by subsequent continuous trading session.