SEBI has opened a consultation on how expiry-day settlement prices for index and single-stock derivatives should interact with the Closing Auction Session, or CAS. The important point for traders is that SEBI has proposed alternatives; it has not yet made either proposed methodology the final operative rule.
The consultation follows SEBI’s earlier review of how CAS could affect derivatives whose final settlement depends on underlying cash-market prices. It now puts specific settlement methodologies, market-timing configurations and auction-related operating changes before market participants for comment.
What the SEBI CAS consultation changes right now
The immediate change is the information state, not the operative settlement rule. Earlier, market participants knew that SEBI intended to review the interaction between CAS and derivative settlement. The September 12 consultation now sets out concrete alternatives and asks stakeholders which approach should be adopted.
That distinction matters because a consultation paper is not the same as a final circular. Traders should not assume that a proposed formula, trading schedule or order-handling rule is already effective merely because it appears in the consultation.
Option 1: Blended VWAP
Under the first consultation option, SEBI proposes a Blended VWAP approach for expiry-day settlement. The methodology would combine pricing information from the final 30 minutes of continuous trading with the 10-minute Closing Auction Session.
The purpose is to reduce the risk that the final settlement value of an expiring derivative depends too heavily on one short pricing window while still incorporating the price-discovery process created by CAS.
Option 2: retain CTS VWAP initially
The second option would retain the continuous-trading-session VWAP approach initially rather than immediately moving to the blended methodology. The consultation also contemplates a possible later transition toward the blended approach.
This means the consultation is not simply asking whether CAS should exist. It is asking how the cash-market closing process should interact with the price used to settle expiring derivatives.
Other CAS changes SEBI is consulting on
The settlement formula is only one part of the consultation. SEBI is also seeking feedback on alternative market-timing configurations and on how information and orders should be handled during the closing process.
Among the areas under consultation are whether an indicative index value derived from the Indicative Equilibrium Price should be disseminated during CAS, restrictions on certain order cancellations or modifications, and the treatment of pending iceberg orders. These points affect how the auction operates and how market participants manage orders near the close.
Has SEBI already changed F&O expiry settlement rules?
No final replacement methodology has been established by this consultation alone. The current controlling rules remain relevant until SEBI completes the consultation process and issues any final regulatory instrument, followed where necessary by exchange implementation instructions.
Readers should therefore separate three states: what applies today, what SEBI is proposing, and what SEBI eventually adopts. Treating those states as interchangeable could lead to an incorrect assumption about how an expiring position will actually be settled.
Who is affected
The consultation is directly relevant to participants in index and single-stock futures and options, particularly on expiry days. Brokers, exchanges, clearing participants, institutional desks and sophisticated retail traders may also need to track any eventual operational changes because settlement methodology and closing-session timings can affect expiry-day workflows and price risk.
What traders should do now
There is no evidence-backed reason to treat either consultation option as the new final rule today. Traders should continue to follow the currently applicable exchange and SEBI framework while monitoring the consultation and any later circulars.
Market participants who want to submit views can use SEBI’s official public-comment process. The consultation’s comment deadline is October 3, 2026.
What remains unknown
SEBI has not yet established which settlement option will be adopted, whether the proposals will be modified after consultation, what the final market-timing arrangement will be, or the effective date of any final change. Those are future lifecycle states rather than confirmed facts today.
What happens next
The next verified material checkpoint is the October 3 public-comment deadline. After considering feedback, SEBI may issue a final circular or other regulatory decision. Any exchange-specific implementation schedule, effective date or operational transition should be treated as a later update to this same article rather than as proof that the consultation proposals were already final.
Verification note
ThePulseSignal reviewed SEBI’s consultation listing, SEBI’s official public-comment interface, SEBI’s earlier September review announcement and current corroborating reporting. The consultation itself is confirmed; the final methodology and effective date remain unresolved.
