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 plans to contest a finding by India's financial regulator that the U.S. trading firm engaged to manipulate the country's markets, the Financial Times reported on Monday.

India has temporarily barred Jane Street Group LLC from accessing the local securities market for alleged index manipulation, dealing a severe hit to the US firm that made $4.3 billion in trading gains there in more than two years.