An even application of plausibility? A legal study of the application of the principle of legal certainty to the plausibility threshold in relation to pharmaceutical patents in European patent law

Sammanfattning: The plausibility threshold started, and is still, developing through the case law of the EPO. It is used as a tool against speculative patents, as the claimed technical effect of the invention must be made plausible. The plausibility threshold is foremost being used at the EPO in relation to the requirement of an inventive step under Article 56 EPC and the requirement of sufficiency of disclosure under Article 83 EPC, even though it is not mentioned within any of those provisions or anywhere else in the EPC. In order for the patent system to fulfil its fundamental purpose, namely to properly work as incentives for innovation, it is crucial that the system provides legal certainty for applicants, patent owners and third parties. However, an uneven application of the plausibility threshold could potentially be inconsistent with this fundamental purpose. Therefore the purpose with this essay was to examine and discuss the application of the principle of legal certainty to the plausibility threshold in relation to pharmaceutical patents in European patent law. For fulfilling the purpose of this essay, plausibility was examined in the pre-grant procedure through the case law of the EPO, as well as post-grant procedure through Swedish and UK case law. In this regard it was concluded that it has been applied unevenly within and between those jurisdictions. Plausibility was moreover examined in relation to Markush type claims as they are broad by their very nature and, thus, risk creating legal uncertainty. On the other hand they are considered as the most precise way of defining chemical compounds, and are important for innovation within the pharmaceutical sector. In this regard it was concluded that the plausibility threshold originate specific issues. Finally it was discussed if there should be a provision on plausibility within the EPC to tackle these uncertainties, with the conclusion that it could be a good solution. Although, only if such a provision could be formulated in an unambiguous way.