Term of patent

The term of a patent is the maximum period during which it can be maintained into force. It is usually expressed in number of years either starting from the filing date of the patent application or from the date of grant of the patent. In most patent laws, renewal annuities or maintenance fees have to be regularly paid in order to keep the patent in force. Otherwise the patent lapses before its term.

The term is calculated from the Indian application filing date as it is applied thoruigh conventional route

Yes, it is correct. Because priority date only justifies about the actual ownersip date of the patent application, whereas the date of filling is the actual date when the application has submitted to the patent office. And this date is important as for as the term of the patent. In normal case it is 20 years from the date of filling. In your case it is 20 Mar 2016 when the patent will expire if all other requirment of maintaing patent is fullfilled regularly.

The term of a patent in case of international application filed under PCT  designating India ,shall be20 years from the international filing date accorded under PCT.This amendment was introduced because otherwise the priority application used to have more than  20 years protection( 20 years from date of filing in India and the period from the date of priority and filing in India)section53

T.R.Subramanian