Jane Street Group, founded in 2000, is a global proprietary trading firm headquartered in the U.S., renowned for its advanced quantitative models, high-frequency trading, and algorithm-driven strategies. Unlike hedge funds, Jane Street trades exclusively using its own capital rather than managing outside investors’ money. The firm operates in multiple regions including the U.S., Europe, and Asia, and employs over 2,600 professionals worldwide.
In India, Jane Street conducted business through four entities: JSI Investments Pvt Ltd, JSI2 Investments Pvt Ltd, Jane Street Singapore Pte Ltd, and Jane Street Asia Trading Ltd. These firms collectively handled its trading operations in Indian financial markets, especially derivatives trading involving index options.

How Did Jane Street Make Rs 36,500 Crore — Allegedly?

Between January 2023 and March 2025, Jane Street’s Indian entities reportedly generated massive profits exceeding Rs 43,289 crore from trading index derivatives, primarily Bank Nifty options. After accounting for losses in other areas such as stock futures and cash equity, their net gain stood at around Rs 36,502 crore.
SEBI’s 105-page investigation highlighted two principal manipulation tactics:
•    Intraday Index Manipulation Strategy: On January 17, 2024, Jane Street executed its largest single-day profit of Rs 734.93 crore by aggressively buying stocks like ICICI Bank, Axis Bank, and HDFC Bank in the morning, artificially inflating the Bank Nifty index. Simultaneously, it took large short positions in Bank Nifty call options at high premiums and long positions in put options at low prices. By selling the stocks later in the day, the index fell, making their put options highly valuable while call options expired worthless — guaranteeing huge profits.
•    Extended Marking the Close Strategy: On options expiry days, Jane Street allegedly manipulated prices near the market close, a critical window for settling contracts. This strategy alone reportedly contributed Rs 17,319 crore in profits from Bank Nifty options. Trades were timed in concentrated bursts aligned with expiry timings, further intensifying price movements.

SEBI’s Response and Broader Market Implications

In response to these findings, SEBI invoked powers under various sections of the SEBI Act, banning all Jane Street entities from Indian securities markets and freezing Rs 4,843 crore in assets. The firm has been given 21 days to reply or seek a hearing. SEBI accused Jane Street of violating the Prohibition of Fraudulent and Unfair Trade Practices (PFUTP) regulations, misleading retail investors, and colluding across multiple entities to distort market dynamics. Notably, the company disregarded cautionary notices issued by the NSE in early 2025.

Jane Street has yet to publicly admit wrongdoing and is expected to defend its trading activities as legitimate arbitrage and hedging strategies.

This case is among SEBI’s most significant crackdowns on a foreign trading firm, spotlighting vulnerabilities in India’s futures and options market, especially during expiry sessions when prices can be more easily influenced. It is expected to prompt stricter regulatory oversight, tighter rules on algorithmic and high-frequency trading, and enhanced protections for retail investors.

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