As I mentioned in my previous post, NRIs from US cannot open online trading accounts (I am not sure about DEMAT account) because under US laws the trader needs to be registered in US and be subject to US laws, I guess no traders want this.
As regards registering with Indian address, its illegal/unlawful. If you are a NRI but declaring yourself as a resident you are making false declaration and breaking FEMA regulations, SEBI/RBI/etc.., guidelines. The Tax department/Govt can easily check through PAN number about your transactions and query source of funds, tax returns, etc.., My understanding is that most US NRIs trade in the name of resident relatives. The RBI is even looking at this practice.
The Indian Govt is making it further difficult by insisting on PAN number for all sort of things and introduced the KYC requirement for Mutual Funds (above Rs 50000/-), in the KYC one has to declare resident status.
As regards registering with Indian address, its illegal/unlawful. If you are a NRI but declaring yourself as a resident you are making false declaration and breaking FEMA regulations, SEBI/RBI/etc.., guidelines. The Tax department/Govt can easily check through PAN number about your transactions and query source of funds, tax returns, etc.., My understanding is that most US NRIs trade in the name of resident relatives. The RBI is even looking at this practice.
The Indian Govt is making it further difficult by insisting on PAN number for all sort of things and introduced the KYC requirement for Mutual Funds (above Rs 50000/-), in the KYC one has to declare resident status.