I don't think you answered my question. I know that stamp duty is charged as per client's state. most of the informed traders know that I guess. Every broker charges stamp duty as per state it's not only you who is doing something special. You are here to help and answer what people ask. If you are not allowed say I am not allowed to answer this, or you can say right now I do not have the details, as get I will post, like this hope you understand.
Stamp Duty is supposed be a fix std per state, there should be clear computation on that.
I also used to think that way but one broker charged me too much more than the brokerage.
We are charging Stamp duty as per the ANMI (Association of National Exchange members of India) guidelines. You can check it further here :- http://www.anmi.in/index.php/information
regards