Episode 36

This time, I will explain the concept of similarity in designs.
Design similarity arises in two contexts: the examination stage (Article 3, Paragraph 1, Item 3 of the Design Act) and the post-registration stage (Articles 23 and 24, Paragraph 2 of the same Act).
According to a Supreme Court judgment (Supreme Court Judgment, March 19, 1974, Third Petty Bench, Case No. 45 (Gyo-Tsu) of 1970; *Minshu* Vol. 28, No. 2, p. 308):
1. A design similar to a registered design (Article 23 of the Design Act) refers to a design that, when applied to an article identical or similar to the article associated with the registered design, evokes an aesthetic impression in general consumers similar to that of the registered design.
2. Based on the above, the similarity referred to in Article 3, Paragraph 1, Item 3 of the Design Act concerns the similarity of aesthetic impressions regarding the design of an article, viewed from the perspective of general consumers.
3. Article 3, Paragraph 2 of the Design Act removes the restriction regarding the identity or similarity of articles; instead, it focuses on the novelty or originality of the design's concept—viewed from the perspective of a person skilled in the art—based on motifs that are widely known in society.
In this Supreme Court judgment, the Court rejected the "creation by a person skilled in the art" theory regarding design similarity and adopted the "confusion by general consumers" theory.
However, it was pointed out that some court precedents and practices evaluated design similarity from the perspective of persons skilled in the art (such as designers). This coexistence of differing judgment methods—diverging from the Supreme Court precedent—led to a lack of clarity regarding how design similarity is determined (as noted in the explanatory materials for the 2006 amendment).
Consequently, Article 24, Paragraph 2 was added to the Design Act during the 2006 amendment, stipulating that "the determination of whether a registered design and another design are similar shall be made based on the aesthetic impression evoked through the visual perception of consumers." Taking into account the numerous court precedents that adopt the perspectives of traders and consumers when determining the similarity of designs, the law was stipulated to base such determinations on the presence or absence of a common aesthetic impression evoked in "consumers"—rather than "general consumers" (Commentary on Industrial Property Laws).
So, who exactly constitutes a "consumer"? The "Roof Tile Case" (Intellectual Property High Court Judgment, June 12, 2023; 2023 (Gyo-Ke) No. 10008) serves as a useful reference here. This lawsuit sought the rescission of a trial decision (Invalidation Trial No. 2021-880006) regarding the invalidation of a design registration under Article 48, Paragraph 1, Item 1 of the Design Act (on the grounds of violating Article 3, Paragraph 1, Item 3).
In that judgment, the court held: "While the determination of whether a registered design and another design are similar is based on the aesthetic impression evoked through the visual perception of consumers (Article 24, Paragraph 2 of the Design Act), the article pertaining to the design in question—roof tiles—involves not only the construction contractors who install them as consumers but also the clients (property owners) who order the roofing work and become the owners of the finished product; these clients are also significant consumers. Furthermore, even construction contractors must ultimately prioritize the aesthetic perspective of the client following installation. Therefore, the assessment of aesthetic impression—a key factor in determining similarity for the design in question—should be conducted from the perspective of the aesthetic values ​​prioritized by the client after installation, rather than solely from that of the construction contractor."
However, there is a logical leap in this lawsuit: the court based its similarity determination on Article 24, Paragraph 2 of the Design Act, even though the issue at hand concerned similarity under Article 3, Paragraph 1, Item 3. Ideally, the determination should have been grounded in Supreme Court precedent (Supreme Court Third Petty Bench Judgment, March 19, 1974; 1970 (Gyo-Tsu) No. 45; *Minshu* Vol. 28, No. 2, p. 308). When assessing similarity based on the aforementioned Supreme Court precedent—which focuses on "similarity of aesthetic appeal from the perspective of ordinary consumers"—the determination must be based on the aesthetic appeal as perceived by the client (the party ordering and ultimately owning the roof) rather than by the construction contractor performing the work. While the conclusion remains the same, the underlying reasoning differs.
On the other hand, in infringement litigation, similarity at the time of infringement is assessed based on Articles 23 and 24(2) of the Design Act. If a defense of invalidity is raised in such litigation, similarity at the time of the examination decision is assessed based on Article 3(1)(iii) of the Design Act. Although both assessments rely on "aesthetic similarity from the perspective of general consumers," this perception can change over time.
In recent years, the spread of social media and similar platforms has shown that the values ​​held by general consumers can shift rapidly. Consequently, a design might be deemed dissimilar at the time of infringement but similar at the time of the examination decision, or vice versa.
If, in future infringement litigation, a party can demonstrate that "aesthetic similarity from the perspective of general consumers" has changed over time, it is possible that court rulings will emerge where the determination of similarity differs between the time of infringement and the time of the examination decision.