The Federal Court of Justice in Germany (BGH) dealt with this question in the decision X ZR 47/22 - "Aminopyridin".

The reason for this was a revocation action that was brought before the European Patent Office (EPO) while opposition appeal proceedings were still ongoing.

According to Section 81(2) of the Patent Act, an action for a declaration of revocation of the patent cannot be filed as long as an opposition can still be filed or opposition proceedings are pending. The revocation action would therefore be inadmissible because of the pending European opposition appeal proceedings.

However, the BGH has now decided that the assessment of whether there is an impediment to the action pursuant to Section 81 (2) of the Patent Act should not be based on the time when the action was filed, but on the time of the decision on the action (reference to X ZR 124/ 10 "Toll Calculation").

In addition, the BGH determined that the term "pending" does not mean that an objection procedure has been finally concluded. Rather, the pendency is no longer given "when the European Patent Office has decided that the patent is to be maintained with an amended version of its claims and this decision can no longer be appealed."

In practice, this is of great importance, especially with regard to the chronological sequence. If a patent is maintained in amended form during oral proceedings in appeal proceedings before the EPO, the basic steps are as follows:

• Adoption of the appeal decision
• Remittance to the opposition division
• Translation of the patent claims into the other official languages
• Payment of the printing fee for the B2 typeface

It can take more than a year from the oral hearing, which determines the final version of the claims, to the formal conclusion of the opposition proceedings.

This means that, according to old case law, in cases of doubt it also takes more than a year before an action for nullity can be brought, although the claims that are to be declared null and void are already known.

According to the "aminopyridine" decision, this period no longer has to be waited for. Rather, the inadmissibility according to § 81 (2) of the Patent Act ceases to exist de facto at the end of the oral hearing. This leads to a considerable shortening of the period of time in which a German revocation action becomes inadmissible.

Theoretically, it is now possible to file a revocation action as soon as the date of the oral hearing is known or published. The action for annulment depends on the outcome of the oral hearing; if the patent in suit is declared null and void by the Board of Appeal, the revocation action brought is inadmissible. It is therefore questionable whether this makes monetary sense for the plaintiff.

According to the new case law, it is now permissible to bring a revocation action parallel to pending opposition proceedings, theoretically when the date of the oral proceedings has been published, but in any case when the European Patent Office has decided in which version the patent is to be maintained.

Source:
BGH X ZR 47/22 – “aminopyridine” BGH on parallel opposition and revocation proceedings - aminopyridine decision (wolterskluwer)