The Bombay Stock Exchange (BSE) has imposed special margins on 33 scrips, including four media shares.

The media firms included in the list of companies on which the margins were imposed are Padmalaya Telefilms, Pritish Nandy Communications, Sri Adhikari Brothers Television Network Ltd and Tips Industries Ltd. The trading margins imposed on the four scrips are at 25 per cent.

Similar trading margins had been imposed on 11 February on three of the scrips in this list - Padmalaya, PNC and Sri Adhikari.

The rates of special margins have been revised keeping in view the closing price of the scrip on the last day of the settlement, a BSE release says.

Margin money is like a security deposit that is paid - which is held until a deal is complete and all monies are settled. The aim of margin money is to minimise the risk of default by either counter-party (buyer or seller). The payment of margin ensures that the risk is limited to the previous day's price movement on each outstanding position. Such measures are normally taken by the exchange to check excessive speculative trading.