NEW DELHI: Markets regulator Sebi has barred leading stock exchange NSE from securities market for a period of six months in co-location case.The regulator has also asked the exchange to disgorge an amount of Rs 624.89 crore along with interest calculated at the rate of 12 per cent per annum to the Investor Protection and Education Fund (IPEF).NSE has also been directed to audit its systems at frequent intervals.Sebi has also issued orders against 16 individuals including former managing directors and CEOs Ravi Narain and Chitra Ramkrishna.The co-location case dates back to 2015, when a whistle-blower wrote a letter to Sebi alleging that the NSE gave preferential access to a few high-frequency traders and brokers to the exchange’s trading platform. Finding Narain guilty in the case, Sebi has asked him to disgorge 25 per cent of the salary drawn for FY11 to FY13 to the IPEF.In case of Ramkrishna, she has been asked to disgorge a quarter of her salary drawn for FY14. She has also been prohibited from associating with a listed company or a market infrastructure institution for a period of five years.More to come…