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DE – Improved analysis and measurement methods

25 Sep 2018

LG Düsseldorf, Improved analysis and measurement methods, judgment of 12.07.2018, 4a O 36/17 (not yet published)

The Regional Court in Düsseldorf had to decide on a peculiar case. It is common in German Patent law, that the knowledge of an average specialist at the time of the filing date/priority date is decisive for claim construction. However, what happens if analysis and measurement methods evolve between the filing date and the time of litigation, had to be decided in Düsseldorf.

The Claimant’s patent relates to a mixture of peculiar antibodies and its acid variants. According to the patent, these acid variants shall have a smaller part than 25% within the mixture. The Claimant sees its patent infringed by a pharmaceutical that – using a method from the time of the filing date – has clearly less than 25% of acid antibodies and – using a new available method – has more than 25% of acid antibodies.

The Court argues, that it is decisive how the specialist understood the term “less than 25%” at the priority date. It is established jurisprudence that knowledge, achieved after the decisive date, cannot be used to determine the scope of protection of a patent. This principle is supposed to guarantee that the scope of protection will remain unchanged until the claim itself gets altered or the patent revoked. If the patent relates to a peculiar value – without reference to a special measurement method – the specialist understands this value as absolute.

If every available measurement method at the time of the priority date would have come to the result that the mixture has a share less than 25% of acid antibodies, the pharmaceutical is infringing the patent even if new methods show a bigger share. If new methods are more sensible and, therefore, can detect a bigger share of acid antibodies than 25% within the pharmaceutical, this exceeding share cannot be taken into account.

The Court, therefore, determined the Defendant’s pharmaceutical to be infringing the Claimant’s patent. In essence the Court is in favour of using the measurement technique available at the time of the priority and therefore in favour for legal certainty. In a review one of the presiding judges of the Düsseldorf Court of Appeal (who will not be handling the appeal in this case) was very much in favour of the decision.

Reported by Alexander Haertel & Dr. Katharina Brandt, Kather Augenstein Rechtsanwälte