Jane Street Fights $503 Million Market Manipulation Case

Jane Street is facing an increasingly intense legal battle with India’s securities regulator, SEBI, over allegations that the trading firm manipulated the Bank Nifty index to generate unlawful profits.

The dispute dates back to July 2025, when SEBI accused Jane Street and related entities of using coordinated trades across Bank Nifty constituent stocks, futures, and options. According to the regulator, Jane Street allegedly bought large quantities of bank stocks and futures while simultaneously building bearish positions in Bank Nifty derivatives. SEBI said the subsequent reversal of those stock positions helped move the index in a direction that benefited its derivatives trades. The regulator estimated alleged unlawful gains at approximately ₹4,843 crore, or around $503 million.

Jane Street has consistently denied the allegations, arguing that its trading represented legitimate index arbitrage rather than market manipulation. The firm has also challenged SEBI’s handling of the investigation and requested access to additional documents, including communications between SEBI and the National Stock Exchange.

The case has become particularly contentious because Jane Street says earlier surveillance reviews did not establish evidence of manipulation. The firm has pointed to previous NSE and SEBI surveillance work covering 53 trading windows, arguing that the Bank Nifty moved against the alleged manipulation strategy in most of those periods.

The latest hearing has added another layer to the dispute. SEBI told the Securities Appellate Tribunal that Jane Street has already received more than 10 GB of data and should focus on explaining its trading conduct rather than seeking additional investigative material. Jane Street, meanwhile, continues to argue that critical information remains unavailable.

The outcome could have implications well beyond Jane Street. The case is testing how aggressively regulators can scrutinize sophisticated trading strategies in one of the world’s largest derivatives markets.