Problems with Multiple Priority Claims in the EPO

A novel theory of “exhaustion” of priority rights is found in an isolated European Technical Board of Appeal decision from April 2005 that denies priority to a second European application where a first European application claims priority to the same foreign parent application, even though both European applications are filed within one year of the foreign parent. According to the IPKat in July 2005:

The EPO Board of Appeal caused much consternation with its decision T0998/99 (OJ EPO 4/2005, 240), stating that "Article 87(1) EPC does not provide for the
possibility of filing several applications in respect of the same subject matter
and therefore of the same invention in one and the same country over the
priority period on the basis of a single priority document" (headnote 1). Most
observers thought that this concept of "exhaustion of priority" was against both
the letter and the spirit of the priority provisions of the EPC and the Paris
Convention.

Fortunately, a recent decision T 0015/01-3.3.4 (relating to EP 0587780), restores sanity and states that: "The board concludes that the priority system of the EPC allow patent applicants to claim and enjoy the same priority right in more than one European application. The doctrine of exhaustion of priority rights is to be rejected."

A referral to the Enlarged Board of Appeal was considered, but rejected for the rather odd reason that "the board is not aware that the doctrine of exhaustion of rights has ever been applied or explicitly addressed in the first-instance practice of the EPO, or, with the exception of the of decision T 998/99, in the case law of the boards of appeal".

Although the IPKat notes that future boards of appeal can choose which decision to follow, Dr. Holger Glas, Dr. Andreas Dilg, and Ignaz Gall, of Maiwald Patentanwalts GmbH (http://www.maiwald.de/), in Munich, Germany suggest in an APLF Update on December 19, 2005 that

"For the time being, to be on the safe side, special care should be taken when
claiming priority in proceedings before the EPO. Smart filing strategies might
include filing multiple priority-establishing applications or filing Divisional
Applications. Moreover, T 998/99 might even be advantageous for the opponent in
Opposition Proceedings to attack the effective date of an European Patent in
dispute."