Patent Court 2025Heo10293: Changed Claim-to-Prior-Art Mapping as a New Ground for Rejection
Pine IP Firm
July 8, 2026
On February 12, 2026, the Korean Patent Court revoked the Intellectual Property Trial and Appeal Board's decision in Case No. 2025Heo10293. The Board had relied on the same prior-art reference cited during examination but mapped two claim elements to different parts of that reference. The court held that the changed mapping was a new ground for rejection because it changed the differences to be addressed and the applicant's available amendment strategy.
The application concerned a multilayer coating that produced a visual effect. Claim 1 included a high-clarity gel-coat layer, a visual-effect layer, and a color layer. Prior Art 1 was a Japanese unexamined patent publication concerning an ink composition and a resin-molded article.
During examination, the examiner used the following correspondence:
| Claim 1 element | Prior Art 1 element identified during examination |
|---|---|
| High-clarity gel-coat layer | Gel-coat layer |
| Visual-effect layer | Intermediate layer |
| Color layer | White layer |
The applicant's opinion and amendments responded to that mapping, including the asserted relationship between the visual-effect layer and the prior art's intermediate layer.
In dismissing the appeal from the refusal, the Board continued to rely on Prior Art 1 but used a different correspondence:
| Claim 1 element | Prior Art 1 element identified by the Board |
|---|---|
| High-clarity gel-coat layer | Gel-coat layer |
| Visual-effect layer | Ink-composition layer |
| Color layer | Intermediate layer |
The cited document did not change, but the technical comparison did. The ink-composition layer, intermediate layer, and white layer served different functions in Prior Art 1. Mapping the claimed visual-effect layer to the ink-composition layer therefore presented a different issue from mapping it to the intermediate layer.
The court treated claim-to-prior-art mapping as a central part of the inventive-step analysis. That analysis requires identification of corresponding elements, determination of similarities and differences, and an assessment of whether a skilled person could readily overcome the differences.
A changed mapping does not automatically create a new ground for rejection. The relevant inquiry is whether the change materially affects:
The court found those effects in this case. If the ink-composition-layer mapping had been notified during examination, the applicant could have argued that the prior-art layer contained ordinary pigments rather than visual-effect pigments. It also could have considered an amendment directed to particle size or other properties of the visual-effect pigment. The examination-stage notice did not give the applicant an opportunity to make those submissions.
The court accordingly held that the Board's reasoning did not correspond in its main thrust to the previously notified ground for rejection. The Board was required to notify the new ground and provide an opportunity to submit an opinion and amendment.
In the revocation action, the Commissioner argued that the examination-stage inventive-step reasoning still supported the refusal. The court rejected that argument as a basis for preserving the Board's decision. The absence of the required opportunity to respond was a procedural defect in the decision under review; a later argument that a different rejection rationale was substantively correct did not cure it.
Articles 63 and 170 of the Korean Patent Act protect the applicant's opportunity to address a ground for rejection before an adverse decision is made. That opportunity includes both legal and technical argument and, where permitted, amendment of the claims.
Case No. 2025Heo10293 does not prohibit the Board from refining an inventive-step analysis. It requires a new notice when the refinement changes the substance of the comparison and the applicant's response or amendment options.
