Comment on Basics on Options Shorting/Writing
Gurmeet, don’t know how ICICI works, but at Zerodha it doesn’t really work the way you have mentioned. If you use our SPAN calculator, you will see that the margins required doesn’t go up incrementally the way you have mentioned. A 8800 Put requires 15100 in margin and a 8900 PE requires 16200, when Nifty is around 8886. So the margin requirement goes up by only Rs 1000 for a put that is 100 points more in the money.
The thing I have seen with most brokers is that they don’t really have a tool like SPAN calculator, so most of the support staff end up telling some random rule to convince the client. Exchanges use SPAN by Comex to determine margin requirement, our SPAN calculator mirrors that.