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".

A study by the Securities and Exchange Board of India found that retail investors lost more than $20 billion on option trades over three years. On July 4, SEBI announced it would seize 48.4 billion rupees ($570 million) from trading giant Jane Street Group,

Jane Street categorically denied any wrongdoing. "We reject the premise and the substance of the Order in the strongest possible terms," the firm told employees in an email