(1)(a) Subject to the provisions of paragraph (3), this Treaty shall enter into force three months after eight States have deposited their instruments of ratification or accession, provided that at least four of those States each fulfill any of the following conditions:
(i) the number of applications filed in the State has exceeded 40,000 according to the most recent annual statistics published by the International Bureau,
(ii) the nationals or residents of the State have filed at least 1,000 applications in one foreign country according to the most recent annual statistics published by the International Bureau,
(iii) the national Office of the State has received at least 10,000 applications from nationals or residents of foreign countries according to the most recent annual statistics published by the International Bureau.
(b) For the purposes of this paragraph, the term "applications" does not include applications for utility models.
(2) Subject to the provisions of paragraph (3), any State which does not become party to this Treaty upon entry into force under paragraph (1) shall become bound by this Treaty three months after the date on which such State has deposited its instrument of ratification or accession.
(3) The provisions of Chapter II and the corresponding provisions of the Regulations annexed to this Treaty shall become applicable, however, only on the date on which three States each of which fulfill at least one of the three requirements specified in paragraph (1) have become party to this Treaty without declaring, as provided in Article 64(1), that they do not intend to be bound by the provisions of Chapter II. That date shall not, however, be prior to that of the initial entry into force under paragraph (1).
Source: http://www.wipo.int/pct/en/texts/articles/a63.htm
Date retrieved: 17 May 2021