After grant a European or German patent may be attacked with an opposition. The time limit for filing an opposition is nine months for European patents and – at present – three months for German patents. A nullity action is possible only after closure of all opposition proceedings (see German article of 24/05/2006). As a rule, an opposition is advantageous compared to a nullity action (see German article of 04/01/2008), in particular because of the lower cost risk (article of 01/10/2009).

The balance is likely to shift even further towards filing oppositions, as a recent Federal Court of Justice (BGH) headnote decision indicates  (judgment of 17/7/2012 – X ZR 117/11 – Polymerschaum). With this judgment, the BGH remanded the case at hand back to the Bundespatentgericht (BPatG) as lower instance court, and from the reasoning it may be concluded that this will happen more often in the future, whereas such remittals had occurred very rarely in the past.

First instance nullity cases are heard by the Nullity Senates of the BPatG. These Senates are staffed with technical judges. They have technical or natural scientific university degrees as well as several years of job experience in that respective technical or scientific field. Second and last instance is the BGH as court of appeal. The judges of the competent X. Civil Senate of the BGH usually exclusively have law degrees without any specific (minimum) technical background. Therefore, over the decades it had become a routine in nullity appeal proceedings that the BGH called in an independent external technical expert.

After a law amendment in 2009, the rules of procedure for nullity appeals have been streamlined in order to avoid this regular consultation of external experts (article of 01/10/2009). All factual issues shall now be exhaustively dealt with in the first instance by the BPatG. Therefore, the new law stipulates that an appeal case should usually be returned to the BPatG if its judgment cannot be affirmed and questions of fact still need to be resolved. As an exception, the BGH “may” nonetheless finally decide the case if this appears to be “pertinent” (section 119 para. 5, 1st sentence, of the revised German Patents Act (PatG)).

The present judgment “Polymerschaum” indicates that the BGH will rather rarely use the alternative to bring cases to an end. According to the headnote, it “predominantly depends on how the open technical issues can be resolved quickly and efficiently”. The reasons of the decision show that the BGH regards the BPatG due to the expertise of its technical judges to be able to avoid consulting an external technical expert. In cases, however, where the BPatG has nevertheless to lean on assistance by an external technical expert, e. g. for carrying out experiments, the BGH expects the BPatG with its technical judges to be in a better position to give proper directions for the external expert. These rather general considerations apply for every nullity case with unresolved technical issues. Thus, remittals are to be expected fairly often in the future. This will not only prolong the duration of the cases but also increase the cost risk, since in terms of legal fees the reopened proceedings before the BPatG count as a new instance. In order to avoid remittals, the parties will have to pay even more attention to detailed factual substantiation of their arguments in the initial phase of the proceedings, e. g. by retaining private experts to carry out experiments and present the result in privat expert opinions.