International Application [Patent] Law and Legal Definition

International application as applied in patent law refers to an application under the Patent Cooperation Treaty (PCT) for patent protection in specified member nations. An international patent application involves two phases. The first step is the filing of an international (patent) application with a suitable patent office, called a Receiving Office. The international application needs to be filed in one language only. At least one applicant must be a national or resident of a contracting state to the PCT.

Then a search is performed by an International Searching Authority (ISA), which provides a written opinion regarding the patentability of the invention. An international preliminary examination may optionally be requested. Finally, the relevant national or regional authorities administer matters related to the examination of application and issuance of patent.