Once patent protection of a drug substance expires, generic companies can sell a generic form of a drug, which typically has development and market approval costs that are a tenth of those of the original drug, allowing generic companies to sell the drug at a fraction of the original’s price. Pharmaceutical companies, therefore, wish to extend the patent life of their drugs for as long as possible to maintain exclusivity and thereby high profits. This extension is made possible through second medical use patents, which allow a company to protect a novel aspect (e.g. new use/indication, dosage, patient group) of an already known drug. Generic companies are then allowed to sell their generic drug under a skinny label, wherein the novel use, dosage or patient group is excluded from the label. However, even if generic companies use a skinny label, they could still be liable for patent infringement under certain circumstances, as described below. For example, if a third party, such as a doctor, used the drug for an indication protected by a second medical use patent, the generic company could be indirectly liable for the infringement.

This so-called indirect infringement is a source of great legal uncertainty because the enforcement of European patents is a national issue and does not fall under the centralized rules of the European Patent Convention. Hence, national courts decide patent infringement matters based on national laws, which often lack clear rules on indirect patent infringement. Thus, not only is the individual outcome of an indirect infringement trial uncertain, but courts of member states could rule entirely differently. Recently, courts of member states of the EPC have issued interesting decisions in this field. These offer essential guidance for future rulings in Europe and might lead the way to a more uniform handling of indirect patent infringement matters.