https://www.epo.org/en/service-support/faq/searching-patents/asian-patent-information/russian-federation/general-4
Is Russia a member of the Patent Cooperation Treaty (PCT)?
Yes, the country joined the PCT on 29 March 1978 as the Soviet Union, and membership was continued by the Russian Federation as from 25 December 1991. Since then, it has been possible to designate Russia in international patent applications filed via the PCT route.
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