Season 2, Episode 97 | 2026-08-06

The First Sensex Auction Expiry. Why The Vol Is Rising, Not Crushing

Here is a correction to the textbook, and it is the whole story of today. Yesterday the RBI held, repo unchanged at 5.25 percent, a neutral stance.

Verdict: 4/5 | 4 HIT, 1 MISS | graded next morning against NSE settlement data.

Cold Open | Forget The Textbook Today

Yesterday the governor did exactly what everyone expected, held at 5.25 percent, neutral stance. And here is where the textbook gets corrected, because after a boring hold volatility is supposed to collapse. Look at the screen. It did not. The volatility on the Sensex is rising, the expiry straddle staying fat, the vol gauge popping. The reason is the whole story of today. This is the first ever Sensex weekly expiry that settles under the new single auction close, the same auction that misfired twice on the Nifty this week. Nobody knows how it will behave, and when the market does not know how…

The Tape | Fade The Event, Buy The Dip

Nifty closed 24,624, basically flat, but the path told the story. It gapped up to 24,700 at the open, sold off through the ten o'clock decision to a 24,497 low by midday, then bought all of it back in the last two hours to close right on the 24,600 line. Sensex 78,581, up 152, same pattern. One tell worth noting, even on the calmest day the Nifty auction still settled about 50 points above where it was trading. That was the Nifty on an ordinary day. Today is the Sensex, on its first expiry under the new rule. Different animal.

The Hero Block | Settlement Itself Is The Risk

Every Thursday the Sensex weeklies settle on the closing price. Until now that close was a thirty minute average, smooth, hard to move. From this week it is a single auction price discovered in one short window at the bell, and on the Nifty that window misfired twice, printing the index nearly 190 points away from where it traded. Think about a Sensex options seller today. Sell the 78,500 straddle expecting a quiet pin, and if the auction prints a couple of hundred points away from where the market traded all day, the short is settled against a number that never really existed. The desks know …

Positioning And Overnight | Coiled Under A Foreign Wall

On the Nifty the foreign funds turned aggressive on the ceiling, adding 63,594 short calls stacked into 24,600 and 24,700, betting the top is 24,700. But the pros bought 1,47,214 calls, the domestics bought nearly 2900 crore of stock and absorbed the foreign selling whole, and the crowd stayed long. A coil, a foreign wall against a bullish everyone else. Overnight the lead is soft and we open up anyway. The Nasdaq slipped nearly a percent, Asia is red across the board, Japan down over 1 and Korea down almost 4, and still GIFT sits at 24,704, opening the Nifty right at the 24,700 wall. Gold pus…

The Edu | Why Vol Rises Into An Untested Expiry

Normally volatility falls into an expiry. The decay of time and the pinning to max pain crush the premium on the last day, and the smart trade is usually to sell it. But that only holds when the settlement is predictable. The moment the way the market closes becomes uncertain, the settlement stops being a formality and becomes a fresh source of risk, and vol rises instead. Two glitchy auctions taught everyone the closing print can jump, and now the same untested mechanism runs on a Sensex expiry for the first time. The option is not just pricing where the index goes, it is pricing whether the …

The Plan | Three Rules, Then The Levels

Rule one, do not sell options into this close, and not just today, until the auction earns trust, which could take weeks. Selling a straddle into a first ever Sensex auction expiry is picking up pennies in front of an unknown machine. Rule two, if you want a position, the safer side is to buy, owning the straddle or a cheap wing means an auction shock pays you. Rule three, the simplest, do not trade the last fifteen minutes at all. Stand aside from about 3:14 and let the auction get absorbed. On levels, the Sensex sits near 78,600 with max pain 78,500, a flat pin is what should happen, but the…

Highlights

RBI held 5.25 percent neutral exactly as consensus expected
The textbook IV crush did not come vol is rising into the untested expiry
First ever Sensex weekly expiry under the single auction close
The Nifty auction misfired twice this week printing nearly 190 points away
Nifty closed 24,624 flat after 24,700 open 24,497 midday low dip bought
Sensex 78,581 up 152 the same fade and recover pattern
Even the calm day auction settled the Nifty about 50 points high
FII added 63,594 short calls stacked into 24,600 and 24,700 betting the top
Pros bought 1,47,214 calls the other side of the foreign wall
DII bought nearly 2900 crore absorbing the foreign cash selling whole
Asia red Japan down 1 Korea down almost 4 and GIFT still 24,704
Gold near a record 4279 the safe haven bid alive under the calm
Sensex max pain 78,500 day priced wide roughly 77,600 to 79,200
Rule one do not sell options into this close until the auction earns trust
Rule two the safer side is buying the straddle an auction shock pays you
Rule three stand aside from 3:14 let the auction get absorbed
Nifty buy dips toward 24,500 stop 24,400 break of 24,700 opens 25,200

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Verdict: 4/54 HIT, 1 MISSGraded next morning against NSE settlementFull track record →

How the grade landed

Graded Thu 6 Aug EOD. The first Sensex auction expiry settled clean, basis minus 1.16, but the INDICATIVE price spiked hard inside the uncrossing window before settling, so the vol bid thesis paid inside the auction rather than in the settlement. The do not sell into the close and stand aside rules were exactly right. Roughly a four.