1. Case Overview

The Plaintiff filed a petition for a negative scope confirmation trial to confirm the scope of the Defendant’s registered design right with the Intellectual Property Trial and Appeal Board (IPTAB), asserting that their design “Plaintiff’s Design” (Article: Mask) does not fall within the scope of the Defendant’s design “Registered Design” (Article: Mask).

The IPTAB dismissed the petition, ruling that the two designs are similar. The Plaintiff subsequently appealed the IPTAB decision before the IP High Court (formerly named “Patent Court”) and finally before the Supreme Court. On January 8, 2026, the Supreme Court finally dismissed the Plaintiff’s appeal (Case No.: 2025Hu10235).

 

2. Key Issues

1. Similarity of Designs: Whether the Plaintiff’s Design shares dominant features with the Registered Design, and therefore gives an overall similar aesthetic impression. Specifically, whether the shared dominant features should be excluded when similarity is being assessed on the basis that they are “forms indispensable for function.”
2. Eligibility to be used as a “Free-to-use Design”: Whether the Plaintiff’s Design could have been easily created by a person of ordinary skill in the art from prior designs known before the Registered Design was filed, and thus falls outside the scope of the Registered Design regardless of any result of a direct comparison.

 

3. Court’s Ruling and Reasoning

A. Judgment on Design Similarity (Consistent between IP High Court and Supreme Court)

The Court reaffirmed the established legal principle that whether designs are similar must be determined by comparing the overall aesthetic impressions, focusing on the “essential parts.”

• Commonalities and Dominant Features: The designs share a two-tiered upper/lower structure, a semi-circular ear-loop shape, and a protruding “beak-like” (bird’s beak) shape over the mouth and nose. The Court found that the combination of these elements forms a unique “frog-like” appearance, which constitutes a dominant feature that captures the consumer’s attention.
• Evaluation of Differences: While the Plaintiff argued there are differences in the number and arrangement of ventilation holes and detailed curvatures, the Court viewed these as “commercial or functional variations that an ordinary designer could apply” or “minor differences detectable only through minute observation.”
• Functional vs. Aesthetic Forms: The Court ruled that even if a shape serves a function, if alternative designs exist (i.e., the shape is replaceable), it possesses aesthetic value and is not purely functional. Therefore, such elements are significant and must be fully considered when similarity is being assessed.
• Conclusion: The Court held that since the dominant features are similar and create similar overall aesthetic impressions, the Plaintiff’s Design is similar to the Registered Design.

B. Judgment on “Free-to-use Design” Defense

The Plaintiff argued that the Plaintiff’s Design is a “free-to-use design” because it could be easily derived from a combination of Prior Designs 1, 5, and 12.

• Detailed Analysis: The Court determined that even if the prior designs share some elements (such as the beak shape), it would not have been easy to combine them to achieve the specific “clean and refined frog-like aesthetic” of the Plaintiff’s Design. Notably, the Court pointed out that Prior Design 12 has a bumpy texture, which differs significantly from the smooth aesthetic of the Plaintiff’s Design.
• Conclusion: The Plaintiff’s Design is not a free-to-use design.

 

4. Significance and Implications

 A. Emphasizing “Dominant Features” when Assessing Aesthetics

This ruling clarifies that similarity should be judged based on the “dominant image” (in this case, the frog-like appearance) formed by the combination of elements, rather than based on a comparison of each element in isolation. This serves as a warning to those who are attempting or are thinking about attempting to circumvent design rights through making minor numerical or structural tweaks.

B. Creating New Aesthetics through Combining Known Elements

The Court specified that even if individual components are already known, if a new combination thereof evokes a unique aesthetic impression not found in the prior art, the creativity of that combination should be highly valued. This holding effectively strengthens the scope of design protection that can be secured.

C. Strictly Applying “Free-to-use” Defense

The decision demonstrates that the free-to-use design defense is difficult to establish unless the core aesthetic of a design can be “easily implemented” by combining prior art. This holding promotes the stability of design rights and protects right holders from indiscriminate imitation.