The Xa. Patent Senate of the Federal Court of Justice dismissed a claim for both literal and equivalent patent infringement after the plaintiff had successfully based his claim on literal patent infringement in first and second instance and only in third instance asserted equivalent infringement.

According to the German doctrine of equivalence, the scope of a patent reaches beyond the literal sense of the wording of the claim. An embodiment that does not satisfy the integers of a patent claim in the literal sense infringes the patent by way of equivalence if the following three so-called Schneidmesser questions1 can be answered in the affirmative:

  1. Does the variant solve the problem underlying the patented invention with modified means which have objectively the same effect?
  2. Is a person skilled in the art able by means of his general technical knowledge to find the modified means as having the same effect?
  3. Are the considerations to be applied by the skilled person so closely oriented to the essence of the technical teaching protected in the patent claim that the skilled person considers the variant with its modified meanings as equivalent to the solution provided by the invention as defined in the claim?

Under German procedural law, the first instance court (here: the district court) and the second instance court (here: the court of appeal) deal with factual and legal issues, whereas in third instance, the Federal Court of Justice only carries out a legal review of the case. Hence, the parties must bring forward all their factual allegations in first and second instance. As the construction of a patent is a matter of law, the assessment of literal or equivalent infringement is purely legal. However, the technical circumstances relevant for this legal assessment are facts.

In the case at issue, before the first and second instance courts, the plaintiff had successfully based his claim on literal infringement only. Correspondingly, all his factual allegations related to literal infringement only. When the case was brought before the Federal Court of Justice, the plaintiff alternatively claimed equivalent infringement but did not substantiate the underlying facts (with regard to the Schneidmesser questions).

The Federal Court of Justice found there was no literal patent infringement.

With regard to the claim of equivalent infringement, the court held that if such a claim was only asserted before the Federal Court of Justice, this was not to be dismissed in general. Rather, the case should be referred back to the court of appeal in order to give the plaintiff the opportunity to substantiate this claim. The reason is that the court of appeal has the duty to advise the plaintiff on the construction of his patent claim if it finds that literal infringement shall be denied. In such circumstances, the plaintiff might consider bringing forward factual allegations relating to equivalent patent infringement in the second instance. However, the case was not to be referred back if the plaintiff was not able to demonstrate that he would have brought forward relevant facts relating to an equivalent infringement after an advice by the court of appeal on the necessity of such substantiation.

In the case at issue, the plaintiff could not show that the defendant's variant solved the problem underlying his patented invention with modified but equivalent means. Therefore, the court found that there was no indication that the plaintiff would have been able to substantiate his claim for equivalent infringement before the court of appeal.

As a result, the Federal Court of Justice dismissed the claim for patent infringement also in respect of equivalent infringement.

The decision shows that the plaintiff does not necessarily need to be the early bird by substantiating his claim for equivalent infringement already in first or second instance. The assertion only before the Federal Court of Justice, however, bears a certain risk and will only lead to a referral back to the court of appeal for factual review of equivalent infringement if the plaintiff can demonstrate that he would be in the position to substantiate his claim