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. A single filing of an international application is made with a Receiving Office (RO) in one language. It then results in a search performed by an International Searching Authority (ISA), accompanied by a written opinion regarding the patentability of the invention, which is the subject of the application. It is optionally followed by a preliminary examination, performed by an International Preliminary Examining Authority (IPEA).[1] Finally, the relevant national or regional authorities administer matters related to the examination of application (if provided by national law) and issuance of patent. https://en.wikipedia.org/wiki/Patent_Cooperation_Treaty SVFC