The Securities and Exchange Board of India (SEBI) has reverted to using the final 30 minutes of trading for settling derivatives on expiry days. This decision follows concerns about sharp price swings caused by the new closing auction system. The revised approach will use a volume-weighted average during the final trading period, as outlined in a circular issued late Thursday. The changes will be implemented starting December 7. This move aims to stabilize market conditions and reduce uncertainty for traders.