유럽의 신뢰성(Plausibility) 법리 및 한국 특허제도로의 수용 방안

Plausibility in European patent practice is not a statutory requirement, but rather a legal principle developed through case law of the European Patent Office (EPO) and UK courts. It is primarily applied in the assessment of inventive step and sufficiency of disclosure. The criterion for plausibility is whether there is some reason to believe, based on the specification, to believe that the claimed effect is credible. This paper reviews the development of plausibility jurisprudence in EPO and UK courts and explores whether and how it might be incorporated into the Korean patent system. In particular, it examines whether the plausibility jurisprudence could be applied to assess the incompleteness and enablement requirements for medical use inventions and selection inventions. This paper begins by reviewing major decisions of the EPO and UK courts to analyze how the plausibility standard has been applied in European patent practice. Then, it compares the enablement requirements in Korea and the United States with the European approach to plausibility. Unlike Europe, neither Korea nor the United States has developed a comparable principle as a preliminary step in assessing enablement. While European plausibility jurisprudence, is primarily applied to the fields of chemistry, life sciences, and pharmaceuticals and lacks a statutory basis, the enablement requirements in Korea and the U.S. are statutory and apply across all technical fields. Plausibility is a useful tool for substantively assessing whether the requirements for patentability are satisfied. This paper classifies medical use inventions and selection inventions into four categories based on the extent to which the effect is described in the specification, and applies the plausibility standard to determine whether each category constitutes an incomplete invention or satisfies the enablement requirement. Current Korean case law tends to assess enablement for medical use inventions in a mechanical manner, focusing primarily on the presence or absence of pharmacological data. The introduction of the plausibility jurisprudence would enable a more substantive examination of whether such inventions meet the enablement requirement. Furthermore, Korean case law has offered limited discussion on the enablement requirement for selection inventions. However, as with medical use inventions, the plausibility jurisprudence could also be applied to assess whether selection inventions satisfy the enablement requirement.