The Securities and Exchange Board of India on Tuesday barred the National Stock Exchange from the securities market for six months. The market regulator also directed to disgorge, or give up, interest worth Rs 625 crore in the co-location case along with 12% interest, Moneycontrol reported.

Under the NSE co-location facility, those trading on the exchange can place their servers in the exchange’s data centre, gaining faster access to stock prices.

In July 2016, SEBI had ordered the NSE to allow an independent agency to investigate allegations that it had given some traders preferential access to its co-location facility. The accused brokers in the case allegedly carried out high-frequency transactions from 2010 to 2014.

The market regulator initiated enforcement action against several entities trading on the NSE in June 2018.

On Tuesday, SEBI found former NSE Managing Directors Ravi Narain and Chitra Ramkrishna guilty in the case. It ordered Narain to disgorge 25% of his salary drawn between 2011 and 2013 and told Ramkrishna to do the same for the 2013-’14 financial year. The market regulator also prohibited both from associating with any listed company for five years, CNBC TV18 reported.

SEBI said that the disgorgement amount must be deposited in the Investor Protection and Education Fund within 45 days by demand draft.