Mumbai, Oct. 16 -- The Securities and Exchange Board of India (SEBI) has revised the closing auction session (CAS) framework, modifying auction timings, order-entry rules and the settlement methodology for expiring stock and index derivatives contracts. Most of the changes will take effect from 7 December 2026, while provisions governing the transition of unexecuted limit and iceberg orders into the auction session will come into force on 8 February 2027.

Under the revised framework, CAS will operate from 3:30 p.m. to 3:40 p.m. on all trading days. The transition from continuous trading to the auction will take place between 3:30 p.m. and 3:31 p.m. Both market and limit orders will be permitted from 3:31 p.m. to 3:36 p.m. Thereafter, onl...