8.9.4 Trial and hearing
For criminal patent infringement to be established, (i) a valid patent right should exist, (ii) the product or process practicing the patent right should be within the protective scope of the patent right, (iii) the alleged infringer’s practice of the patent right should be unlawful, (iv) the alleged infringer should have the ability to fulfill their legal responsibility, and (v) the alleged infringer should have intent. We will mainly discuss requirement (ii) below, as it is most challenged in practice.
8.9.4.1 Whether the practiced product or process falls within the protected scope of the patent right
As in a civil patent lawsuit, the protective scope of a patented invention should be defined first to determine patent infringement. Thus, an interpretation of the scope of claims is required first, with a focus on the language and text stated in the scope of claims (principle of literal interpretation), while also taking into account the descriptions and drawings of the invention and common technical knowledge at the time the application was filed (principle of reference to the descriptions of the invention).186
Additionally, to determine patent infringement, the elements stated in the patented invention’s scope of claims and the elements of the infringing product or process should be compared based on claim construction, and the elements that are stated only in the descriptions of the invention should not be compared. To fall within the protective scope of a patented invention, the defendant’s product or process must include all elements of the patented invention. If only some of the elements of the patented invention are included, with the rest missing, then the product or process does not fall within the protective scope of the patented invention in principle.187
Patent infringement includes both literal infringement and infringement under the doctrine of equivalents. Therefore, patent infringement may be established in a case where the elements of the defendant’s product or process are not literally identical but instead equivalent to the corresponding elements of the plaintiff’s patented invention.
However, whether indirect infringement can constitute patent infringement is an issue. Court precedent takes the position that indirect infringement is fundamentally a preparatory act of infringement, and, since the punishment of a preparatory act of a criminal act requires a specific provision therefor, the provision to punish patent infringement cannot itself be used in punishing indirect infringement, a preparatory act of infringement.188
8.9.4.2 Grounds for patent invalidation in criminal patent infringement cases
In cases where the elements of a patented invention are identical to those of the prior art known at the time of patent application and thus lack novelty, the patented invention has no scope of the right worth protecting regardless of the absence of an invalidation decision, and, thus, patent infringement is not established.189
Whether a lack of inventive step can be reviewed in a criminal patent lawsuit is an issue. As discussed above, in a civil patent lawsuit, the defendant typically argues against the plaintiff’s patent infringement claim to the effect that it is an abuse of rights based on a clearly invalid patent right that lacks an inventive step, and such a defense has been upheld as valid.190 Although there has not yet been explicit precedent in a criminal lawsuit, it is a common view that no criminal infringement will be found if the patented invention is found to be lacking an inventive step upon review. However, in practice, if a lack of an inventive step is alleged, the trial will generally proceed in consideration of the progress of the related judicial and administrative trials.
8.9.4.3 Intent and unlawfulness
Criminal patent infringement requires the infringer’s intent. The term “intent” here refers to the awareness and acceptance of patent infringement;191 it cannot be readily concluded that an infringer has criminal intent on the sole basis of a registered patent. Where a right holder becomes aware of another person’s act of infringement, they may secure evidence of intent by sending a warning letter to the infringer.
However, the Criminal Act provides that “[w]hen a person commits a crime mistakenly believing that his or her act does not constitute a crime under the laws and regulations, he or she shall not be punishable if the misunderstanding is based on reasonable grounds.”192 In this regard, an issue arises as to whether this provision applies when a defendant has been advised, for example, by a patent attorney on patent infringement. Courts tend to take a strict view as to whether such advice may be construed as a justifiable ground for the misunderstanding of law: the mere fact of receiving advice is not enough to escape punishment.
8.9.4.4 Number of offenses
As the legal interest sought in a patent infringement lawsuit is to protect the patent right, then even if one person has committed multiple infringements, a single comprehensive offense may be established if the unity and continuity of their criminal intent is recognized.193 In other words, in such cases, multiple infringements are treated as one offense. In addition, regardless of whether the right holder is the same, only one offense of infringement is established for each patent right.