The Central Bureau of Investigation (CBI) on Sunday night arrested former managing director (MD) and chief executive officer (CEO) of National Stock Exchange Chita Subramanian in Delhi in the co-location case after her anticipatory bail plea was rejected by a Special CBI court on Saturday.

“She will be presented before a Delhi court on Monday morning,” a CBI official said under condition of anonymity.

CBI had arrested former group operating officer of NSE Anand Subramanian last week. 

CBI may also seek extension of Subramanian’s custody on Monday whose 10-day custody ended on Sunday.

The arrests were made in the case related to the co-location scam, the FIR for which was registered in May 2018, amid fresh revelations about irregularities at the country’s largest stock exchange. 

The CBI had last month questioned Ramkrishna, Subramanian and Ravi Narain, also former CEO of the NSE.

A report of the Securities and Exchange Board of India last month showed that Ramkrishna took key decisions at the NSE from 2013 to 2016 on the advice of a “Himalayan yogi”, whom she had never met and who instructed her to appoint Subramanian group operating officer.

The four-year-old FIR of the CBI was primarily against Sanjay Gupta, MD of OPG Securities. 

It also named his brother-in-law Aman Kokrady and Ajay Shah, a data specialist and researcher employed by the NSE, along with unknown officials of the NSE and Sebi for their role in the controversy.

Between June 2010 and March 2014, the NSE had deployed the so-called tick-by-tick (TBT) architecture at its colo facility. TBT disseminated data feed sequentially, giving preference to trading members (TM) that had connected first to the colo server.

Transcripts of mail correspondence between Chitra and Himalayan saint going viral in social media

Taking advantage of the system, OPG Securities frequently obtained first access to the exchange system in connivance with certain NSE staffers. 

The issue was brought to light by a whistleblower, Ken Fong, who sent three complaint letters to Sebi in January, August, and October 2015, following which the regulator initiated multiple investigations and forensic audits into the matter.

In April 2019, Sebi directed the exchange to disgorge Rs 625 crore, along with an interest of 12 per cent annum since 2014, for lapses at its colo facility, which allowed unfair access to certain brokers. Sebi also told Narain and Ramkrishna, who were at the helm when the exchange servers were exploited, to disgorge a fourth of their salary for a specific period.

The market regulator directed OPG Securities, Gupta, and three others to disgorge Rs 15.6 crore, with an interest of 12 per cent per annum since April 2014. 

All of them have moved the Securities Appellate Tribunal against the order, where the matter is currently being heard.