Korean commentators have opined that there is a doctrine of equivalents in Korea. However, the reported Supreme Court decisions seem to cast doubt on this conclusion. The Court held that addition of a catalyst introduced a new technical concept that was not encompassed by the claims of the patent in suit. Appeal lies to a High Court which is entitled to hear additional evidence. Validity of a patent is in principle a matter exclusively for the jurisdiction of the Patent Office.
Patent infringement gives rise to both civil and criminal liability.
The maximum penalty is a fine of 20,000,000 won or five years corrective labor. Most evidence and argument is by way of written submission but oral statements of witnesses may be heard. Some provision for discovery exists although there is no deposition practice. In Korea it is possible for the either party to a potential infringement suit to request a ruling from the Patent Office on the scope of the claim and this determination is given significant weight but a court trying an infringement action. Appeals from decisions as to the scope of the claim may be made to the Patent Court.