India's securities regulator is preparing to rewrite the rules that determine how derivatives contracts are settled, just days after the launch of its most ambitious market-structure reform in years ran into turbulence. The Securities and Exchange Board of India (SEBI) said it will review the methodology used to price settlement of futures and options trades, with a consultation paper expected within a week, according to people familiar with the deliberations and media reports in Outlook Money, Mint and Analytics Insight.
The review follows a bruising debut for the Closing Auction Session (CAS), a new mechanism for setting the closing price of stocks that SEBI has positioned as a landmark overhaul of how Dalal Street's trading day ends.
A Rocky First Week for 'Dalal Street's Biggest Reform'
The CAS was designed to replace the long-standing practice of deriving a stock's closing price from the volume-weighted average price of the final half hour of trading. Instead, it consolidates end-of-day demand and supply into a single call auction, a structure regulators argue is harder to manipulate and more transparent.
In practice, the transition has been anything but smooth. The new mechanism produced sharp price swings, thin order books and acute concentration in derivatives activity around the closing window, unnerving market participants and prompting urgent exchanges between brokers and the regulator. One report described the rollout as "Dalal Street's biggest stock reform in years" — and one that "endures rocky first week."
Liquidity was the central complaint. Because closing prices feed directly into the settlement of equity derivatives, any distortion in the auction ripples through the country's enormous — and retail-heavy — futures and options market.
Regulator Moves to Loosen the Logjam
SEBI has moved on two fronts. First, it asked brokers to continue accepting client orders throughout the closing auction transition, a measure aimed squarely at deepening the liquidity pool during the new session. Brokers confirmed the directive, which effectively prevents members from withdrawing from the auction window while the system beds in.
Second, the regulator signalled it is willing to revisit the mathematical plumbing of derivatives settlement itself. Bloomberg reported that SEBI will review options settlement pricing after the closing auction chaos, while Mint and MSN both reported that the regulator will propose changes to derivatives settlement prices following the hurdles encountered by CAS.
"The initial liquidity issues with CAS are seen across global markets."
That framing came from the SEBI chair, who used the episode to argue that teething problems with closing auctions are a well-documented international phenomenon rather than a uniquely Indian failure — a defence that also touched on the regulator's expanding use of artificial intelligence in market oversight, according to Rediff and Business Standard.
'Could Have Been Better Prepared'
Not everyone is convinced. U.K. Sinha, a former SEBI chairman, offered a notably blunt assessment: the regulator could have been better prepared for the closing auction's introduction, The Hindu BusinessLine reported.
The critique cuts at a recurring theme in Indian market reform — the tension between the speed of regulatory change and the operational readiness of brokers, exchanges and clearing corporations. Vendors must upgrade order-management systems, exchanges must recalibrate matching engines, and retail investors must relearn when and how their orders execute. When those pieces move at different speeds, the cost shows up as volatility.
Why the Stakes Are So High
- Settlement linkage: Derivative contracts settle against underlying closing prices, so any auction anomaly transmits directly into payouts across the F&O segment.
- Retail exposure: India's retail derivatives participation has exploded in recent years, magnifying the impact of any pricing dislocation.
- Global benchmark: Closing auctions are standard in London, Tokyo and other major markets, giving SEBI both a template and a shield.
- Precedent: The reform is being watched as a test case for future market-microstructure changes in India.
Markets and Brokers Rally on the News
Paradoxically, the prospect of softer settlement rules lifted the very stocks most exposed to the change. BSE shares jumped about 5% on reports that SEBI would review derivative settlement rules, while a subsequent circular on CAS sent Groww, Angel One and BSE shares up as much as 8%, according to Newsbytes and MSN.
The rally reflects a simple calculus: brokers and exchanges benefit when the F&O ecosystem functions smoothly, and a regulatory rethink reduces the risk of client attrition or operational penalties stemming from chaotic closes.
What Comes Next
The consultation paper, expected within seven days, is likely to canvass alternatives for computing derivative settlement prices — including whether to decouple settlement from the auction entirely, extend the observation window, or introduce safeguards for illiquid strikes. Market participants will have a window to respond before SEBI finalises the framework.
For now, the regulator's message is one of calibrated retreat rather than reversal. SEBI is not abandoning the closing auction; it is buying time and flexibility to fix the edges. Whether that proves enough to restore confidence in a mechanism meant to define the end of every Indian trading day will be determined in the weeks ahead — and in the consultation responses now being drafted by every major broker in Mumbai.
