Patent law update: patents with pre-AIA US priority applications at risk in Europe
Entitlement to priority for successors in title
On 27 September 2017, the District Court in The Hague (the Netherlands) issued a judgment in Celltrion v. Biogen et al. revoking the Dutch counterpart of European patent EP 1 951 304 (EP 304) for lack of novelty. The Court held that EP 304’s priority claim was invalid because priority rights had not been timely assigned by its US employee-inventors to the applicant. This decision raises concerns for the holders of patents claiming the priority date of a pre-AIA US patent application.
Before the Leahy-Smith America Invents Act (AIA), US patent law required that patents were filed by the inventors, rather than by their employer or other assignees. More often than not, the application would be assigned to their employer who would then pursue patent protection in other jurisdictions, relying on the priority date of the US patent application. Article 4 of the Paris Convention for the Protection of Industrial Property provides for an international right of priority of 12 months as of the date of filing of a patent application for filing in other countries. That right is conferred to “any person who has duly filed an application for a patent […] in one of the countries of the Union, or his successor in title”. The same language is used in Article 87 of the European Patent Convention.
EP 304, a patent for a method of treatment of rheumatoid arthritis held by Biogen, F. Hoffmann-La Roche and Genentech, claims the priority of two US patent applications. These applications were filed by two then-employees of Biogen. According to the judgment, the agreement with their employer, subject to the laws of Massachusetts, contained an active assignment of the employees’ rights in “Proprietary Information” and a promise to assign “Inventions” and any rights that the employee may have and acquire in inventions. Priority rights as such are not mentioned in the employment agreement.
Celltrion argued that the right to priority had not been validly assigned to Biogen, so it was not entitled to claim priority as the inventor’s successor in title. The District Court agreed. It dismissed the patentees’ defence that the priority right had automatically been transferred by the assignment of the priority application. Referring to the case law of the Boards of Appeal of the European Patent Office, the Court ruled that a priority right is an independent right that should be assigned separately, in accordance with the national law that applies to the priority application. After an analysis of the provisions in the inventors’ contract, the Dutch court found that neither the clause with the active assignment nor that with the promise to assign covers priority rights. It continued that the parties to that contract “simply neglected to make concrete arrangements for the assignment of priority rights”.
Because the priority rights had not otherwise been assigned to the applicants of EP 304, the Court ruled that they were not the priority applicant’s successor in title at the time of the European application. In result, priority was not validly claimed and the patent was invalidated for lack of novelty over a study abstract published after the priority date, but before the European application date.
The issue of entitlement to priority as a successor in title is a not new one, but the Dutch court’s take on the matter is decidedly strict for patentees. In the United Kingdom, Arnold J held in KCI v Smith, that “successor in title” for priority means successor in title to the invention. In contrast, the The Hague Court in Celltrion v Biogen et al. referred to the EPO Board of Appeal’s decision in T-205/14 to hold that the right to priority is a right that must be distinguished from the right to the priority application. It is correct that this statement is referred to in the Case law of the Boards of Appeal of the European Patent Office at page 369. The Dutch court’s subsequent reasoning that this implies that the right to priority must be separately transferred, however, is not supported by the decision referred to in the EPO’s case law overview. Instead, the Board of Appeal noted in T-205/14 at page 25 that it did not share the opponent’s view that “the characterisation of the right of priority as a right independent of the right to the priority application implies that the valid transfer of a priority right inevitably requires a separate and express assignment declaration. The requirement for a valid transfer of rights of priority is a matter distinct from the characterisation as an independent legal right.”
While the question of entitlement to priority for successors in title is not specific to patents claiming the priority date of a pre-AIA US patent application, it is particularly relevant to such patents because of the requirement that the inventor files the patent application. The Dutch judgment also refers to parallel proceedings before the EPO Opposition Division and the Landesgericht in Munich, Germany. It appears that a preliminary injunction was denied in Germany on account of the likelihood that the priority claim is invalid. These decisions are a red flag for the holders of patents claiming a US priority date. It remains to be seen whether an appeal will be filed in the Netherlands. In the meantime, it can be expected that this decision will bolster attacks against patents with pre-AIA US priority applications in European jurisdictions.
Contact: Kristof Neefs, kristofneefs@ip.be.
Download a PDF version of this update here.