The PCT is an international treaty with more than 150 Contracting States which are bound with certain formal requirements set out in the Treaty and Regulations. The PCT makes it possible to seek patent protection for an invention simultaneously in a large number of countries by filing a single ―international‖ patent application instead of filing several separate national or regional patent applications however, granting of patents remains under the control of the national or regional patent offices after the corresponding ―national phase‖ application has been filed and the national phase application is assessed as per patent law of that jurisdiction.
As per Indian Patent Act 1970 as amended and the Patents Rules 2003 as amended by (amendment) rules 2016, any PCT international application may be filed designating India and it shall deemed to be an application if the corresponding national phase application has also been filed.