The lawsuit alleged that the traders had stolen a “ highly valuable, unique, and proprietary ” trading strategy, which was quickly revealed to revolve around India’s booming options market. Jane Street and Millennium settled the lawsuit in December, but judging from SEBI’s report it has cast a long (and expensive) shadow.

India has barred Jane Street from the country’s financial markets and said it would seize around $570 million that the U.S. securities firm made from allegedly fraudulent trades.

Shares of some Indian stockbrokers and market intermediaries fell on Friday after the country's securities regulator barred U.S. trading firm Jane Street from the local market over alleged manipulation in derivatives trading.