Former MP Kirit Somaiya has urged SEBI to investigate the 2,200-point swing in the BSE Sensex during the Closing Auction Session on August 27. The request highlights concerns that structural gaps in the newly introduced mechanism could make the market vulnerable to price manipulation.
Former Member of Parliament Kirit Somaiya has formally requested that the Securities and Exchange Board of India (SEBI) conduct a thorough inquiry into the market volatility observed on the Bombay Stock Exchange (BSE) on August 27, 2026. During the newly introduced Closing Auction Session, which takes place between 3:20 PM and 3:30 PM, the Sensex experienced a sharp 2,200-point decline before recovering, causing significant concern among traders and investors.
The Closing Auction Session was implemented on August 3, 2026, with the goal of setting a fair final price for the day. However, Somaiya has argued in his letter to SEBI Chairman Tuhin Kanta Pandey that the current design may have structural flaws. A primary concern is the gap in liquidity and timing; standard cash market trading concludes at 3:15 PM, leaving the auction window without the support of continuous market activity. This disconnect, combined with lower participation during the auction, can allow smaller trade volumes to cause disproportionately large price swings, potentially creating an environment open to misuse.
This is not the first time the integrity of the closing price has come under regulatory scrutiny. SEBI recently initiated enforcement actions following suspected price manipulation on August 13, where investigators identified artificial spikes in the equilibrium price and impounded illicit gains. Somaiya contends that the confluence of thin liquidity and high-stakes events, such as monthly derivatives expiry days, necessitates a closer look at whether the current mechanism is functioning as intended.
Despite these concerns and the request for a suspension or redesign of the framework, SEBI leadership has maintained a firm stance. Chairman Tuhin Kanta Pandey has indicated that the regulator does not intend to roll back or change the Closing Auction Session policy, signaling a commitment to the ongoing modernization of market closing procedures.
For investors, the debate centers on market stability and transparency. The closing price serves as a critical benchmark for portfolio valuations, index tracking, and derivatives contracts. As the market adjusts to this new system, the primary monitorable for investors will be how the regulator balances the push for modernization with the need to ensure that the auction mechanism remains resilient against volatility and potential manipulation.