1. Stamp duty depends neither on place of Board meeting nor registered office of the company. It depends upon place of issue of share certificates. If Board meeting is held in Dubai, but share certificates are issued from Mumbai, duty will be payable as per Bombay Stamp Act. (Some companies hold Board meetings in other States where duly is lower, just to have an additional proof to the effect that the share certificates were issued from that State only.)
2. As per Article 17 of Schedule to Bombay Stamp Act, stamp duty in the State is Re.1 for every Rs.1000 or part thereof of the value of shares.