Squaring off by last buyer

Simple question guys

There is a call option say nifty 10800 which is written by seller1 and bought by buyer1

After writing his option seller1 collected premium and went on tour. Now buyer1 bought this option but later sold to buyer2

Buyer2 was the last buyer and it is expiry day and the nifty closed by 10820 which is ITM .

Now people say square off square off but buyer2 could not find buyer3 to sell. Now this will be the same scenario with every option right? There has to be a final buyer with no facility to square off? What will he do? Should he click do not exercises? Or should he calculate STT and if profit is above STT deduction he has to exercise?

Someone please explain from last buyer perspective.

Hi @ksksat,

This link should give you the answer

Cheers,
Lindo

Lindo thanks . this is the usual STT story and using the do not exercise option

My question is let us say it is 3 25 pm and my nifty call @ 10800 and spot is around 10850.

I am not able to square off the buy option.

Now my case is in ITM . I don’t want to leave possible profit by clicking do not exercise

But i am afraid of huge STT by letting the option exercised. But it is not borderline ITM. Even after STT it may result in profit. How to be sure about the exact ITM point above which i start getting profit even after STT?