High Quality Content by WIKIPEDIA articles! The Patent Cooperation Treaty (PCT) is an international patent law treaty, concluded in 1970. It provides a unified procedure for filing patent applications to protect inventions in each of its Contracting States. A patent application filed under the PCT is called an international application or PCT application. The PCT does not provide for the grant of an "international patent", as such multinational patent does not exist, and the grant of patent is a prerogative of each national or regional authority.