World Intellectual Property Organization

Patent Law Treaty (PLT)

The Patent Law Treaty (PLT) aims at harmonizing national patent formalities throughout the world. It is designed to streamline and harmonize formal requirements set by national or regional Patent Offices with respect to the filing of national or regional patent applications and the maintenance of patents and certain additional requirements related to patents or patent applications, for example, communications, representation or recordation of changes concerning patents and patent applications. According to an impact assessment, the implementation of the PLT was considered to have positive impacts on users, particularly in terms of simplification of procedures (document SCT/27/4).


Initially, a draft Treaty containing a wide range of provisions relating to formality and substantive requirements of patent applications, examination procedures, standards for obtaining a patent and rights and remedies under a patent had been negotiated by the WIPO member States since 1983.  During a Diplomatic Conference in 1991, divergent views on major issues became apparent, such as the issues of first-to-file and the grace period.  In 1995, it was agreed that another approach for promoting harmonization, covering matters concerning the formality requirements of national and regional patent procedures, should be initiated by WIPO.  Following this decision, the draft PLT has been discussed first in the Committee of Experts on the Patent Law Treaty, and, since 1998, in the Standing Committee on the Law of Patents (SCP).

After five years of discussions, a Diplomatic Conference, convened from May 11 to June 2,  2000, adopted the Patent Law Treaty on June 1, 2000.  On June 2, 2000, 43 States signed the Treaty and 104 States, the European Patent Organisation (EPO), the Eurasian Patent Office (EAPO) and the African Regional Industrial Property Organization (ARIPO) signed the Final Act of the Treaty.  The PLT was open for signature until June 1, 2001 and 53 States and one intergovernmental organization have signed the Treaty.  The PLT entered into force on April 28, 2005, that is, three months after ten States had deposited their instruments of ratification or accession with the Director General of WIPO (list of Contracting Parties to the PLT).

Main features

The PLT provides, in particular:

  • filing date requirements, and procedures to avoid a loss of the filing date because of a failure to comply with formalities;
  • a single internationally standardized set of formal requirements for national and regional offices, which are in line with the formal requirements under the Patent Cooperation Treaty (PCT);
  • standardized forms which shall be accepted by all offices;
  • simplified procedures before patent offices;
  • mechanisms to avoid the unintentional loss of rights as a result of failure to comply with time limits; and
  • basic principles for the implementation of electronic filing.


Inventors, applicants, and patent attorneys from Contracting Parties - both developed and developing countries – as well as third parties and national or regional offices can benefit from the PLT.  According to an impact assessment, the implementation of the PLT has positive impact on users, particularly in terms of simplification of procedures (see document SCT/27/4).

  • Standardized forms and simplified procedures reduce the risk of errors and thereby result in less frequent loss of rights.
  • A predictable maximum set of patent formalities in all Countries Parties results in easier access to foreign patent systems.
  • The Model International Forms that must be accepted by each Contracting Party also facilitate the filing of applications and various communications abroad.
  • Legal certainty for applicants filing in their home country and abroad, and reduction of costs for inventors, applicants and patent attorneys.
  • The streamlined procedures results in increased efficiency of patent offices in handling national and international applications and a consequent reduction of their operating costs.
  • In countries where a license or a security interest can be recorded, such recordal is facilitated by simplified procedures.

Each Contracting Party is free to prescribe any substantive requirements under its national/regional law, taking into account its development and public policy considerations.  No financial obligations are imposed on a Contracting Party.


Basic information and forms

Members and meetings

Amendments and implementation

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