Ok thanks. I also asked AMPFutures broker and they said it's legal. Futures is regulated. I checked NSE site and we can trade US Dow Jones, S&P 500, FTSE 100 Futures, But they haven't listed Mini-Dow tho. So if NSE allows US DJIA, S&P500 then it's should be possible to open a account with Chicago broker, because they provide both.