India has barred one of the world's largest quant trading firms, Jane Street, from accessing its securities market after an investigation found it made "unlawful gains", taking the most stringent action ever against a foreign trading firm.

SEBI has temporarily barred Jane Street from the Indian stock market and impounded ₹4,840 crore for alleged index manipulation, raising concerns about retail traders' vulnerabilities in derivatives trading.

Following its ₹4,843 crore order against Jane Street Group for alleged index manipulation, Sebi Chairman Tuhin Kanta Pandey issued a stern warning that market misconduct — from domestic or foreign entities — will face zero tolerance.