<p>The new mechanism, known as pre-open session call auction, will last for a duration of 15 minutes and will be introduced on a pilot basis by the BSE and NSE, Sebi said in a circular.<br />In the first 15 minutes, investors can place orders for eight minutes on the basis of which exchanges will determine the rates at which trading will happen.<br /><br />In the next seven minutes, the exchanges will execute the orders at identified rates. A total of 50 companies are listed on the Nifty, while 30 are on the Sensex.<br /><br />In a call auction, participants indicate their willingness to buy or sell units of a security by placing an order for a number of units at the prevailing price.<br /><br />At some point in time, the orders collected are matched to form contracts.</p>
<p>The new mechanism, known as pre-open session call auction, will last for a duration of 15 minutes and will be introduced on a pilot basis by the BSE and NSE, Sebi said in a circular.<br />In the first 15 minutes, investors can place orders for eight minutes on the basis of which exchanges will determine the rates at which trading will happen.<br /><br />In the next seven minutes, the exchanges will execute the orders at identified rates. A total of 50 companies are listed on the Nifty, while 30 are on the Sensex.<br /><br />In a call auction, participants indicate their willingness to buy or sell units of a security by placing an order for a number of units at the prevailing price.<br /><br />At some point in time, the orders collected are matched to form contracts.</p>