Jane Street has told staff it will contest a ban by India's financial regulator which has accused the U.S. high-frequency trading giant of market manipulation, adding that its practices in question were "basic index arbitrage trading".

India’s securities regulator plans to boost its surveillance systems to better detect complex trading strategies after taking action against high-speed trading giant Jane Street Group for alleged market manipulation.

At the heart of the controversy is Jane Street’s aggressive trading in the derivatives (futures) segment, where the firm executed trades designed not just to profit, but to sway the market itself. Here's how.