Under the Second Patent Modernisation Act of August 2021, the following sentence 3, among others, was added to the injunctive relief under Section 139(1) PatG:

"The claim is excluded insofar as the claim would lead to disproportionate hardship for the infringer or third parties not justified by the exclusive right due to the special circumstances of the individual case and the requirements of good faith."

This so-called "proportionality defence" was originally introduced into the Patent Act at the instigation of the automotive industry in order to protect automotive companies from disproportionate patent infringement actions arising from patents (especially from the software and electronics sector) of automotive suppliers. The automotive companies complained that relevant patents were difficult to search for with regard to freedom of operation, but that enforcement of the patents could lead to a complete production stop or recall of their products and thus, especially if an injunction was issued, to enormous unjustified damage for the companies.

However, the present decision did not concern disputes in the automotive sector, but a patent dispute between two pharmaceutical companies, namely the patent holder NuCana suing its competitor Gilead for infringement of its European patent EP 2 955 190 B1. According to the plaintiff, the patent in suit - relating to a chemical compound for the prophylaxis or treatment of cancer - was unlawfully used by Gilead's medicinal products containing the active medical ingredient sofosbuvir for the treatment of chronic hepatitis C. The defendant contested the patent.

The defendant did not contest the patent infringement, but invoked Section 139(1), sentence 3 PatG and argued that, in particular, the issuance of an injunction was disproportionate with regard to the interests of its patients.

However, the Düsseldorf Regional Court rejected the proportionality objection and issued an interim injunction. The court based the rejection on the fact that the defence of proportionality was the result of a comprehensive weighing of interests and that in the case at hand, the defendant had neither made sufficient efforts to obtain a commercial licence for the use of the patented chemical compound nor had it attempted to sue for a compulsory licence at an early stage. Thus, plaintiff NuCana and defendant Gilead had been unsuccessfully negotiating the grant of a commercial licence since August 2021. The defendant finally filed a lawsuit for a compulsory licence in April 2022, only a few weeks before the infringement trial.