Mint Explainer | What’s behind Jane Street’s SAT appeal against Sebi in the index manipulation case

At stake is not only a ₹4,843 crore escrow deposit but also the question of whether Sebi suppressed exculpatory findings while accusing Jane Street of index manipulation.

The core of Jane Street’s appeal is that two earlier reviews—one by the National Stock Exchange (NSE) and another by Sebi’s Integrated Surveillance Department (ISD)—had already cleared its trades. Yet, in July this year, Sebi relied on a new theory to issue a sweeping interim order without acknowledging those findings.

Mint unpacks what triggered the appeal, the contradictions Jane Street highlights in Sebi’s case, the legal arguments being pressed, and the reliefs sought before SAT.

What triggered the appeal?

On 3 July, Sebi passed an ex-parte interim order against four Jane Street affiliates, accusing them of manipulating Bank Nifty index prices on 21 dates to benefit their derivatives positions. The regulator said these trades, some clustered around expiry days, fit a strategy it termed “Extended Marking the Close.” Jane Street was barred from the market and directed to park ₹4,843 crore in an escrow account, which it did promptly.

Jane Street then sought inspection of the records Sebi relied on. While the regulator allowed limited access in August, it withheld several key documents:

• The November 2024 NSE surveillance report that allegedly found no manipulation,
• The December 2024 Sebi ISD report that purportedly cleared Jane Street,
• Internal file notings and NSE–Sebi correspondence, including instructions to alter “objective criteria” when initial reviews showed no wrongdoing, and
• The complaint from a private trader said to have triggered the re-examination.

Sebi formally rejected Jane Street’s demand for full disclosure through two orders on 7 and 22 August. The SAT appeal now challenges those refusals.

What conflicts with Sebi’s allegation?

Jane Street’s plea points to the ISD’s 11 December 2024 report, which examined 53 trading patches. In 48 of those patches—over 90%—the ISD found no evidence that the firm’s trades moved index prices to benefit its derivatives positions, according to the appeal. The remaining five patches yielded negligible profits relative to Jane Street’s broader trading, and the ISD concluded the group’s profit pattern “contradicted any manipulation theory,” the appeal said.

Jane Street contends that rather than closing the matter, Sebi created a fresh team in early 2025, reframed expiry-day trading under the novel “Extended Marking the Close” theory, and generated new analytics in May. Even then, it argues, most trading patches showed no evidence of manipulation.

The appeal also claims that file notings and correspondence, currently withheld, would show how Sebi directed the abandonment of earlier objective criteria once they failed to corroborate wrongdoing.

What legal arguments are being made?

The companies argue that Sebi’s approach violates principles of natural justice by:

• Imposing sweeping restraints without a hearing,
• Denying access to annexures, internal notes, and correspondence referenced in its own files, and
• Forcing them to respond without seeing the very evidence relied upon.

The appeal further questions Sebi’s justification of urgency. Although the 3 July order cited urgency to bypass a prior hearing, Jane Street points out that the regulator spent months reworking its theories after earlier reviews did not support charges of manipulation.

The petition accuses Sebi of suppressing exculpatory evidence, tailoring analyses to reach a predetermined outcome, and misusing its interim powers.

Ketan Mukhija, senior partner at Burgeon Law, said the dispute highlights how SAT routinely handles disclosure challenges. “After Sebi issues an order, any meaningful challenge to its basis or process—including requests for fuller disclosure—must proceed through an appeal to SAT,” he said.

He added that the tribunal has repeatedly reinforced due process norms, holding that Sebi cannot “cherry-pick” evidence and must allow inspection of all relevant materials.

What reliefs are being sought?

The Jane Street entities want SAT to: set aside Sebi’s August refusal orders; direct the regulator to disclose all withheld documents in full, including unredacted trade logs; and restrain Sebi from taking further steps until inspection is complete.

They note they have already deposited the impounded amount in escrow and voluntarily refrained from fresh purchases.

Emails sent to Sebi and Jane Street seeking comment remained unanswered at press time.