# Related designs: can a different top surface leave the same overall impression? Korean Patent Court case 2026Heo10106 considers whether changes to a food-waste processor’s controls and cover outweighed its shared proportions and silhouette. Source: https://www.iplexlaw.co.kr/en/blog/brunch-case-1894 HOME / NEWS & INSIGHTS NEWS & INSIGHTS Related designs: can a different top surface leave the same overall impression? Korean Patent Court case 2026Heo10106 considers whether changes to a food-waste processor’s controls and cover outweighed its shared proportions and silhouette. Designs & Trademarks 2026.10.29 published IPLEX 7 min read A challenge to a related-design registration Korea’s related-design system protects variations similar to the owner’s principal design. This dispute concerned Athome Plentech’s food-waste processor design No. 1306291, filed on 7 March 2025 and registered on 15 May 2025 as a related design. Its principal design, No. 1227721, was filed on 24 April 2023 and registered on 9 August 2023. Both concerned appliances that grind and dry leftover food. Cuckoo Electronics sought invalidation. The Intellectual Property Trial and Appeal Board rejected the request on 27 February 2026 in case 2025Dang2034. Cuckoo then sought cancellation of that decision in the Patent Court, which delivered judgment in case 2026Heo10106 on 7 October 2026. Side-by-side perspective, front and top views of challenged design No. 1306291 on the left and principal design No. 1227721 on the right Similarity to the principal design was the issue Cuckoo argued that the shared features were commonplace, while the top control panel, hinge and other differences created a different impression. It alleged that the registration failed the similarity requirement for related designs under Article 35(1) of the Korean Design Protection Act. The court compared the appearance as a whole, rather than counting isolated similarities and differences. Similar dominant features could produce a similar aesthetic impression despite differences in detail. Both designs were minimalist, with very little ornamentation. Their overall form, proportions and silhouette consequently had a substantial influence on the impression perceived by consumers. Six shared features shaped the overall appearance Both had a tall columnar body with a stadium-shaped top: two semicircular ends joined by straight sides. Smooth curved surfaces connected the front to the sides and the sides to the rear. The ratios between the top’s width and length and the body’s height were extremely similar. A circular control button sat at the upper centre of the front, with no other functional or decorative elements on the front, sides or rear. The top was divided into a broad opening lid at the front and a filter cover at the rear. That rear cover was semicircular and contained multiple narrow slots. The court regarded these six common features as immediately perceptible and dominant. Five differences in the top and button In the challenged design, the control display lay on a flat surface level with the lid and filter cover. In the principal design, it occupied the sloping face of a transverse V-shaped groove between those parts. The challenged design had no hinge, while the principal design had one beside the opening lid. Conversely, the challenged design had a bezel around the filter cover, which the principal design lacked. The challenged design had no patterns between its vertical filter-cover slots, while the principal design had various patterns. Its front button also projected beyond its surround, whereas the principal design’s button was slightly recessed. The court considered these differences minor or most apparent upon deliberate side-by-side inspection. Perspective drawings of the registered and principal designs placed side by side to compare their overall appearance and top layout Functional or familiar shapes still contributed to the impression Cuckoo sought reduced weight for the stadium-shaped body, circular button and semicircular filter cover because they were known forms. The court held that functional or known features could still matter where they contributed to the overall aesthetic impression and attracted attention. Prior designs 1–6 showed alternative proportions, contours and curved surfaces; the body shape was not functionally inevitable. Prior designs 7–12 illustrated different button sizes, positions and surrounding elements. On otherwise smooth, undecorated surfaces, the upper-centre circular button was a visual focus. Its shape and placement were choices, not unavoidable functional requirements. Prior designs 13–15 showed alternatives for the rear filter cover. Here, its semicircular shape divided the top into a large front lid and rear cover, while the vertical slots provided visual emphasis. It was more than an inconsequential functional component. Comparison table of prior designs 1 to 6, showing differing proportions and contours of stadium-shaped columnar bodies Comparison table of prior designs 7 to 12 with different circular-button sizes, positions and surrounding features Comparison table of prior designs 13 to 15 showing different shapes and arrangements of rear top filter covers Frequent use of the top did not outweigh the shared appearance Cuckoo argued that users repeatedly opened the lid and filter cover, making their details particularly noticeable. The court accepted that the panel and hinge could be readily seen during use, but found that the differences occupied a limited part of the top. Those differences did not sufficiently alter the similar impression created by the common form, proportions and silhouette. The related design remained similar to its principal design. The court found no violation of Article 35(1), upheld the Board’s rejection of invalidation and dismissed Cuckoo’s claim. This was a decision on the challenge to the registration. Explain the scale, position and effect of each change For a related-design filing, marking changed details alone may be insufficient. Views from several directions should show the retained features, the location and scale of changes, and their effect on the overall impression. A validity challenge likewise benefits from concrete alternatives and comparisons of proportions and placement, beyond asserting that a feature is functional or familiar. The prior designs here helped demonstrate how similar elements can produce different appearances. The judgment does not establish that hinges or buttons are always unimportant, nor does it decide whether another company’s product infringes. Its lesson is to examine both the changes and the overall appearance that survives them. The original figure labels and forms are preserved; the text explains the source material. Read the Korean source This article reflects the information available when it was published. Contact us to discuss your circumstances. Discuss this topic ↗ All articles Related service: Designs & trade marks ↗ Related service: IP disputes & appeals ↗ ON THIS PAGE A challenge to a related-design registration Similarity to the principal design was the issue Six shared features shaped the overall appearance Five differences in the top and button Functional or familiar shapes still contributed to the impression Frequent use of the top did not outweigh the shared appearance Explain the scale, position and effect of each change TALK TO IPLEX Discuss your IP questions We consider your technology and business needs together. ↗ Contact us Older METAVIEW and metaVu: why pronunciation mattered in Korea ↗ Related insights Designs & Trademarks 2026.10.29 METAVIEW and metaVu: why pronunciation mattered in Korea Korean Patent Court case 2025Heo10544 shows why visual differences between software brands did not overcome identical or highly similar pronunciation. ↗ Read article Designs & Trademarks 2026.10.28 When a design registration is invalidated: loss of legal interest in a scope-of-rights action Korea’s Patent Court dismissed case 2024Heo15950 after the design registration was finally invalidated, while ordering the defendant to bear the litigation costs. ↗ Read article Designs & Trademarks 2026.10.28 Non-use cancellation and service on a bankruptcy trustee in Korea Korean Patent Court decision 2025Heo10 explains why identifying the proper respondent and serving the bankruptcy trustee must precede a decision on trademark non-use. ↗ Read article - https://www.iplexlaw.co.kr/en - https://www.iplexlaw.co.kr/en/blog/category/trademark - https://www.iplexlaw.co.kr/ko/blog/brunch-case-1894 - https://www.iplexlaw.co.kr/en/contact - https://www.iplexlaw.co.kr/en/blog - https://www.iplexlaw.co.kr/en/ip-solutions/trademark#related-insights - https://www.iplexlaw.co.kr/en/ip-solutions/disputes#related-insights - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-0 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-1 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-2 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-3 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-4 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-5 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1894#article-1894-en-6 - https://www.iplexlaw.co.kr/en/contact - https://www.iplexlaw.co.kr/en/blog/brunch-case-1893 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1893 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1893 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1888 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1888 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1887 - https://www.iplexlaw.co.kr/en/blog/brunch-case-1887