A US-based investment firm is under investigation for allegedly manipulating the Bank Nifty index to make illegal gains through aggressive stock buying and selling.

US-based investment firm Jane Street barred from India’s securities markets for allegedly manipulating the stock index and unlawfully earning ₹4,843 crore.

• Jane Street Group, including JSI Investments, JSI2 Investments, Jane Street Singapore, and Jane Street Asia Trading, manipulated Bank Nifty, the index with 12 bank stocks, and unlawfully gained ₹4,843.6 crore.

• SEBI found Jane Street Group aggressively buying ₹4,370.03 crore of Bank Nifty stocks and futures, escalating the prices of Bank Nifty stocks and the index.

• Jane Street built trades of ₹32,114.96 crore of bearish positions in the more-liquid Bank Nifty index options, buying cheap put options and selling expensive call options.

• The group reversed and sold all future positions it had taken, booking losses, which pushed prices down.

• SEBI ordered the group to open an escrow account in a scheduled commercial bank to transfer the unlawfully earned money and directed banks, depositories, and other market institutions not to make debits in Jane Street’s accounts without its permission.