Mumbai, July 4 || In one of the biggest market manipulation cases India has witnessed in recent years, US-based trading firm Jane Street is under the scanner for allegedly using sophisticated strategies to rig Indian stock indices and pocket over Rs 43,000 crore in options profits.
According to the Securities and Exchange Board of India (SEBI), Jane Street and its related entities devised an elaborate intra-day trading strategy to artificially inflate and deflate the Bank Nifty index -- mainly on expiry days -- to gain from massive options positions.
The regulator found that between January 1, 2023, and March 31, 2025, Jane Street entities booked staggering profits of Rs 43,289 crore, largely from Bank Nifty options.
This was allegedly achieved by manipulating prices in the cash and futures market -- with precision, scale, and timing that pointed to deliberate intent.
According to SEBI, the strategy involved aggressive buying of Bank Nifty component stocks and futures during morning trading hours, which caused the index to rise.
As the day progressed, Jane Street would then aggressively sell those very positions, dragging the index down.
This timing was not random. The trades were deliberately made around monthly expiry dates -- when options contracts are settled based on the index’s closing value -- allowing Jane Street to benefit massively from the swings they themselves created.