Reed Smith Client Alerts

Key takeaways

  • This landmark decision from the Enlarged Board of Appeal of the European Patent Office (EPO) changes long-standing practices that often penalized priority claims to U.S. patent applications.
  • Per the decision:
    • The EPO is competent to assess a party’s entitlement to a priority claim.
    • There is a rebuttable presumption that the applicant is entitled to claim priority.
    • When an application filed under the Patent Cooperation Treaty by parties A and B claims priority to an application filed by party A alone, the listing of party B as applicant for the EPO and party A as applicant for somewhere else but not the EPO implies an agreement between parties A and B that party B is entitled to claim priority to the earlier application – thus bolstering the presumption.
  • The decision is binding on practice before the EPO and is likely to influence practice at the Unified Patent Court. The decision may also influence national litigation of European patents, even though national courts are not bound by the decision. Although the decision does not relate to practice regarding national patents, the influence might even extend to national practice as countries in Europe seek to harmonize national practice with each other and with EPO practice.

The ability to claim priority is a central component of patent systems around the world – including under the U.S. system, the European Patent Office (EPO) system, and the Patent Cooperation Treaty (PCT) – and allows the applicant of one patent application to benefit from the earlier filing of another patent application. Thus, a party can for example file a first application (typically at their local patent office), and subsequently file a second application (typically at another patent office) but have the second application be treated as if it had been filed on the same day as the first application, by claiming priority to that first application.

Typically, the applicant in respect of the priority-claiming application is the same as the applicant in respect of the earlier application. However, complications can arise when this is not the case, and such complications have been particularly penalizing for priority claims made to U.S. applications.

Under U.S. practice, for example, it is commonplace for an inventor to file a U.S. application and assign it to an employer in accordance with their employment contract.

Under consideration in the Enlarged Board of Appeal's decision of 10 October 2023 was a situation where the priority of a U.S. application filed in the name of its inventor was claimed by a PCT application that entered into the European regional phase at the EPO: the U.S. application (to which priority was claimed)  was filed by party A (the inventor); the PCT application (which claimed priority to the U.S. application) listed party A as the inventor and also listed party A as the applicant for the U.S. only, but listed party B (the employer of party A) as the applicant for everywhere else (including the EPO).

Such a situation is the result of ongoing and past differences between U.S. practice and practice under the PCT and at the EPO regarding a party’s entitlement to apply for a patent.

Since, in EPO practice – as in many countries in Europe – the priority right is distinct and separately transferrable from the property right, the EPO (and many national authorities) historically have wanted proof that the applicant acquired the priority right of the earlier application before the PCT application’s filing date.