After the Nifty index surged 300 points in seconds during Tuesday's closing session, regulators are considering changes to how derivatives are settled. The volatility, linked to weekly expiry, has led to discussions on shifting away from the current auction-based pricing to a 30-minute average price. Investors may track these updates as they aim to reduce sudden price distortions and stabilize trading in the final minutes of the day.
The National Stock Exchange saw extreme volatility during the closing auction session on Tuesday, October 6, 2026. During the final minutes of trade, the Nifty index jumped over 300 points in just 30 seconds, only to shed 240 points shortly after. This sudden movement disrupted the normal price discovery process and drew immediate attention from the Securities and Exchange Board of India. The Sensex also faced similar, though less intense, instability during this window.
Proposed Changes to Settlement Rules
The closing auction mechanism for stocks eligible for Futures and Options was introduced on August 3, 2026, to help determine a fair final price. However, recent events have highlighted risks, especially on days when derivative contracts expire. Because the current system can lead to sharp price jumps, regulators are reportedly considering a partial reversal of these rules.
The proposed change involves moving back to a 30-minute Volume Weighted Average Price for the settlement of derivative contracts. This approach is intended to prevent the market from being affected by a single, sudden trade or a brief auction window, providing a more stable reference price for traders and investors. The regulator is currently reviewing approximately 20,000 suggestions from various stakeholders and may implement these adjustments by the end of October 2026.
Market Sentiment and Institutional Flows
Despite the technical turbulence at the end of the day, the broader market remained positive. The Nifty settled 1% higher at 22,776, while the Sensex gained 685 points. This resilience was supported by a decline in global Brent crude oil prices, which dropped below the $100-per-barrel mark after international efforts to release oil stockpiles eased supply worries.
Institutional activity played a key role in supporting the indices during the session. Domestic investors bought shares worth Rs 5,089 crore, which helped offset the selling pressure from foreign institutional investors, who net sold Rs 2,961 crore of Indian equities.
What Investors Should Monitor
For investors, the primary takeaway is that the mechanism for determining end-of-day prices is under active review. The risk of sudden price distortions during expiry days remains a factor until official changes are confirmed. Traders and investors should watch for any formal circulars or announcements from the exchange or the regulator regarding the transition to a 30-minute average price model. These updates will be important for understanding how closing prices and derivative settlements will function in the coming months.