The Jane Street-Sebi saga is more than a legal dispute — it’s a litmus test for India’s ambitions as a global financial hub.
Illustrations: Dominic Xavier/Rediff
A legal battle is looming — one that could reshape India’s derivatives market, the world’s largest by trading volume, and set a precedent for how regulators worldwide draw the line between clever trading and market abuse.
The genesis of this battle lies in the sweeping crackdown the Securities and Exchange Board of India has launched against Jane Street, a US-based high-frequency trading (HFT) firm.
Sebi has impounded Rs 4,843 crore in alleged ‘unlawful gains’, accusing Jane Street of orchestrating a sophisticated ‘sinister’ scheme to manipulate the popular Bank Nifty index through aggressive derivative trading strategies.
Jane Street, a global titan in algorithmic trading, has fired back, calling Sebi’s allegations ‘fundamentally mistaken’. The firm is preparing to challenge the ban, likely at the Securities Appellate Tribunal.
The case, which could reach the Supreme Court, has ignited a fierce debate over what constitutes legitimate trading and what crosses into the realm of market manipulation.
With Indian retail investors suffering over Rs 1 trillion in losses in 2024-2025, the stakes are monumental — not just for Jane Street and Sebi, but also for the credibility and future of India’s capital market ecosystem.
The Anatomy of the Allegations
Sebi has laid out its case against Jane Street in a detailed, 105-page interim order, dated July 3, with voluminous annexures.
According to the regulator, the firm executed a two-pronged strategy: It aggressively bought Bank Nifty constituent stocks in both the cash and futures segments, artificially inflating the index.
Later in the day, it offloaded those positions, while holding large short positions in index options, profiting from the index’s decline.
This strategy, Sebi alleges, allowed Jane Street to rake in thousands of crores in profit.
The regulator also hinted that the illicit gains could be even higher since investigations into other expiry days and indices are ongoing.
Jane Street, however, maintains that its trades were part of a standard ‘index arbitrage’ strategy — exploiting price differences between related instruments to provide liquidity and maintain market efficiency.
In internal communications, the firm described Sebi’s order as ‘extremely inflammatory’ and argued that the order disregards the legitimate role of arbitrageurs in modern markets.
Legal Faultlines
The core of the legal dispute hinges on intent and market impact.
Sebi’s case rests on proving that Jane Street violated Sections 3 and 4 of the Sebi (Prohibition of Fraudulent and Unfair Trade Practices relating to Securities Market) Regulations, 2003, and Section 12A of the Sebi Act, 1992.
These regulations prohibit knowingly indulging in an act that creates a false or misleading appearance of trading.
Further, they prohibit indulging in unfair trade practices or employing a scheme to defraud through dealings in the securities market.
The regulator has also pointed to warnings ignored from the National Stock Exchange as evidence of deliberate misconduct.
Smrithi Nair, partner at the law firm Juris Corp, notes that Jane Street’s systematic losses in stock futures and cash segments — Rs 7,208 crore and Rs 289 crore, respectively — could be interpreted as a deliberate cost to execute a manipulative scheme.
“This ‘loss’ may be viewed as a malafide cost incurred to perpetrate their prima facie manipulative and fraudulent scheme,” she said.
Neerav Merchant, partner at Aquilaw, a Kolkata-headquartered law firm, agrees that Sebi’s case appears strong on paper, especially given the detailed trading pattern analysis.
However, the regulator must prove illegality ‘beyond reasonable doubt’.
He adds that the trades will be tested on the grounds whether Jane Street “simply exploited a systemic loophole” and if they “were within the systemic boundaries”.
Doing so might not be easy. “Establishing intent to manipulate — particularly in the context of proprietary trading — is notoriously difficult,” says Diviay Chadha, partner at the law firm Singhania & Co.
Besides, Jane Street may invoke international regulatory precedents, where similar strategies are not penalised.
Tushar Kumar, a Supreme Court advocate, is of the view that the case raises broader questions about balancing competitive advantage with market fairness in a tech-driven trading environment.
The Fallout
The Jane Street case unfolds against a backdrop of massive retail investor losses.
Sebi data shows that retail traders lost trillions in equity derivatives over the past few years.
A staggering 90 per cent — much higher than the global average — of retail traders incurred losses, highlighting the vulnerability of domestic individual investors in a market increasingly dominated by algorithmic players.
The worry is that if proven, Jane Street’s actions would not only distort the market but also erode trust among retail investors, who trade with limited capital and high expectations.
The political dimension adds further pressure to the situation. The Opposition Congress has accused Sebi and the government of delayed action, with spokesperson Supriya Shrinate calling it ‘not a failure, but a sin’.
Such rhetoric could intensify public demand for regulatory reform and greater investor protection.
Regulatory Ripple Effect
Regardless of the outcome, the Jane Street case could trigger regulatory changes.
Jidesh Kumar, managing partner at the legal firm King Stubb & Kasiva, Advocates and Attorneys, believes that if Jane Street succeeds at the tribunal, then it may lead to greater scrutiny of HFTs.
“It may prompt Sebi to revisit its enforcement tools and regulatory framework concerning algorithmic and proprietary trading, particularly by foreign portfolio investors. We may see increased emphasis on surveillance mechanisms, audit trails, and regulatory disclosures to enhance market transparency,” Kumar says.
Sebi Chairman Tuhin Kanta Pandey has already signalled a ramp-up in surveillance, with plans to expand investigations to other indices like the Nifty 50 and Sensex.
Market experts anticipate further measures such as longer-dated expiries and stricter position limits to curb excessive influence by single entities.
While these changes could raise compliance costs for trading firms and potentially reduce liquidity in the short term, they may help restore confidence among retail investors and ensure a level playing field.
Precedent or Pandora’s Box?
If Sebi prevails, it could pave the way for further impounding of gains and stricter enforcement against algorithmic trading strategies.
While a final investigation report may take six to nine months, the market watchdog’s resolve appears firm.
However, if Jane Street wins, it could embolden other HFT firms to push the boundaries of acceptable trading, forcing Sebi to fast-track reforms.
Either way, the case is likely to reach the Supreme Court, where the interpretation of ‘manipulation’ versus ‘arbitrage’ will be tested under Indian securities law.
Shiju P V, managing partner at IndiaLaw, believes the case could shape India’s approach to regulating global trading firms.
“It’s about balancing market integrity with the participation of sophisticated international players,” he says.
The Jane Street-Sebi saga is more than a legal dispute — it’s a litmus test for India’s ambitions as a global financial hub.
With retail investors reeling from its impact and foreign firms watching closely, Sebi must walk a tightrope between fostering innovation and protecting market integrity.
New regulations aimed at curbing manipulative trading practices might inadvertently raise entry barriers for legitimate firms.
The outcome of the legal battle could well be a key test of whether or not the country can effectively oversee high-frequency trading without undermining market liquidity.
Already, the overhaul of the derivatives trading rules — prompted, in part, by the aggressive nature of HFT firms like Jane Street — is beginning to impact market dynamics.
Between December 2024 and May 2025, the number of unique traders in the derivatives segment fell by 20 per cent compared to the same period a year earlier.
Meanwhile, the average daily trading volume in futures and options (F&O) dropped to a four-month low of Rs 346 trillion in June — down 35 per cent from the peak in September, before the new rules took effect. Further declines may be on the horizon.
The trajectory of this legal dispute will ultimately shape the future of India’s derivatives market.
It will determine whether the market can evolve into a fair, transparent, and globally respected platform — or remain a domain where only the most sophisticated players gain at the expense of smaller investors.
Feature Presentation: Aslam Hunani/Rediff