In Decision T 0844/18 CRISPR Cas/Broad Institute, a Technical Board of Appeal of the European Patent Office upheld the revocation of the commercially important European Patent 2771468 because the patent was not entitled to the priority date that had been claimed and was therefore anticipated by documents published after the claimed priority date but before the European filing date. The validity of the claim to the priority date turned on the question of whether Article 87(1) EPC (which tracks the language of Article 4 of the Paris Convention) had been complied with. Article 87(1) reads as follows:
Any person who has duly filed, in or for (a) any State party to the Paris Convention for the
Protection of Industrial Property or (b) any Member of the World Trade Organization,
an application for a patent, a utility model or a utility certificate, or his successor in title,
shall enjoy, for the purpose of filing a European patent application in respect of the same
invention, a right of priority during a period of twelve months from the date of filing of the first
application.
In this case U.S. provisional patent applications from which priority had been claimed had been filed in the names of more applicants than were named in the European application thereby raising the question of whether the European application complied with the requirement of Article 87 that priority could only validly be claimed by the applicants for the provisional application or a successor in title. The EPO Board of Appeal set out the question to be decided as:
“A and B are applicants for the priority application. A alone is the applicant for the subsequent application. Is a priority claim valid even without any assignment of priority right from B to A?”
After consideration of the French text of Article 87 EPC (which uses the words celui qui where the English text says “any”), the Vienna Convention on the Law of Treaties (to conclude that Artile 87 EPC was intended to implement Article 4A of the Paris Convention), the French text of the Paris Convention, this being the only authentic text of the Convention (which uses the words ceui qui in Article 4A) and the policy underlying the of the Paris Convention, and the fact that to the extent that earlier cases had considered the issue they had held that the words “any person” in Article 4A of the Paris Convention meant “all those who had filed the application from which priority was claimed or their successors in title, the Board concluded:
In the light of these considerations the Board finds that the words”any person” in Article 87(1) EPC require that all applicants for the priority application, or their successors in title, are applicants for the subsequent application.
The Board rejected the Appellant’s contentions that such an interpretation unfairly prejudiced applicants who had filed a provisional application covering multiple inventions but who wished to limit their foreign filing to only one of these and name as applicant only those who had invented what was now claimed. The legislative history of the Paris Convention showed that the words “any person” had been chosen deliberately over a rival proposal to refer to inventor sharing the right to claim priority. Furthermore after noting that Article VI clause 2 of the U.S. Constitution incorporated the Paris Convention into U.S. law, the Board commented
it is clear that applicants wishing to use US provisional applications should be aware of the difficulties they may face if they use these applications to claim priority for a European patent application. This is simply a consequence of the US’s adhesion to the Paris Convention.