Patent Law Treaty PLT 2000 was concluded on June 1, 2000, and entered into force on April 28, 2005. Patent Law Treaty is open to States members of WIPO and/or States parties to the Paris Convention for the Protection of Industrial Property. It is also open to certain intergovernmental organizations. As of August 2019, the PLT had 42 contracting states, while 59 states and the European Patent Organisation have signed the treaty. The aim of the Patent Law Treaty is to harmonize and streamline formal procedures in respect of national and regional patent applications and patents, and thus to make such procedures more user-friendly. The Patent Law Treaty provides that Contracting Parties are allowed to exclude paper communications and to fully switch to electronic communications after June 2, 2005.
The Patent Law Treaty provides maximum sets of requirements, which the Office of a Contracting Party may apply and requirements for obtaining a filing date were standardized. The Patent Law Treaty contains, in particular, provisions on the following issues: Requirements for obtaining a filing date were standardized in order for applicants to minimize the loss of the filing date.
The Patent Law Treaty requires that the Office of any Contracting Party must accord a filing date to an application on compliance with three simple formal requirements: An indication that the elements received by the Office are intended to be an application for a patent for an invention. The Patent Law Treaty provides procedures for the avoidance of unintentional loss of substantive rights as a result of the failure to comply with formality requirements or time limits.
Indications that would allow the Office to identify or to contact the applicant; however, a Contracting Party is allowed to require indications on both. With the significant exception of filing date requirements, the PLT provides the maximum sets of requirements the office of a Contracting Party may apply. These include the obligation of Offices to notify the applicant or other concerned person, extension of time limits, continued processing, reinstatement of rights and restrictions on revocation/invalidation of a patent for formal defects, where they were not noticed by the Office during the application stage.