What happened

Yesterday the market spent almost the whole day between 24,550 and 24,600. A quiet, narrow day. Then it closed far above that range.

Today it opened at 24,703 — the highest point it would reach — and sold from the first minute. It broke below yesterday's range. By 3:15 it stood at 24,463, near the day's low.

Then trading stopped.

Twenty minutes later a closing price appeared: 24,614.90.

One hundred and fifty-one points higher than where the market had stopped.

Two days in a row now, the same thing. Monday it added 201 points. Today it added 151.

Why that mattered more today

Today was an expiry. Contracts had to be settled — and settlement uses that closing number.

Two contracts tell the whole story.

A call option at 24,500. At 3:15, with the market at 24,463, it was below the level and heading for nothing. It had fallen most of the day, down to around 25. Then the closing price arrived at 24,614.90 — above 24,500 — and it settled at about 115.

A put option at 24,600. It had risen all day and was worth around 126 at 3:15. Then the closing price came in above 24,600, and it settled at five paise. A loss of 99.93%.

Both were decided in a window when nothing was trading.

Had the closing price been calculated the old way — an average of the last half hour — the results would have been reversed. The call worthless, the put worth about 135.

Same day. Same market. Opposite outcome, decided by which method was used to work out one number.

Now read that again, slowly

Six hours of trading. Every chart, every level, every opinion.

Then twenty minutes with the market shut, and both contracts finished at the opposite of where they had been heading.

This is not a complaint. The new method exists for good reasons and every large market in the world uses one. But it is two days old here, and nobody — including the people who trade this for a living — yet knows how it behaves.

The thing worth saying plainly

Somebody will show you today's numbers as an opportunity. From 25 to 115 in fifteen minutes.

That is not an opportunity. That is a coin toss that landed.

Nobody sitting at 3:15 knew the closing price would print 151 points higher. Not one person. The market was shut. The same toss on Monday would have flipped the other way for anyone positioned the other side.

Weekly options on expiry day, in a mechanism two days old, with a settlement window nobody can see into — that is the single most expensive way for a small account to learn this lesson.

If you take one thing from tonight: do not go looking for that trade.

And it changes again next month

From 7 September, the morning session gets rebuilt the same way. The opening price will also come from an auction, with a random close nobody can time.

So from September, three separate things will need thinking about rather than one: how the day opens, how it trades, and how it closes. They will no longer be the same kind of number.

What you know by tonight

That the closing price is now made in a room you cannot see into.

That on expiry day it decides who was right, and six hours of trading may not.

And that when the rules of a market change, the honest position for a while is I don't know yet. Anyone claiming otherwise, two days in, is guessing with confidence.

Markets were never for everyone. Days like today are simply more honest about it.

This is commentary only. Nothing here is a buy/sell call or a recommendation — no derivatives, no positions suggested. For any personal investment decision, please consult a SEBI-registered adviser.

THE CHAIN
The market froze at 24,463 at 3:15 → twenty minutes later the auction printed 24,614.90, 151 points higher → expiry settlement uses that closing number → so a call that was worthless became worth 115, and a put that was worth 126 became worth nothing → decided entirely in a window when nothing was trading.

TOPICS
Open vs Close · Risk Before Return