The Korean Intellectual Property High Court held that, even when the same prior art reference cited in the Examiner’s rejection is relied upon by the Trial Board when dismissing an appeal against a final rejection, but based on a different interpretation thereof, such different interpretation constitutes a new ground of rejection; and, therefore, that the Trial Board’s dismissal of the appeal without affording the applicant an opportunity to present arguments and amendments in response to such new ground for rejection is procedurally defective (IP High Court Case No. 2025 Heo 10293, rendered on February 12, 2026; final and conclusive).

▶Background of the Case 

The patent application at issue concerned a multilayer coating with visual effects comprising, as essential elements, a visual effect layer and a color layer.

During examination, the Examiner rejected the subject application for lack of inventiveness based on a Japanese patent publication (“prior art reference”), disclosing a multilayer coating including an intermediate layer and a back layer, interpreted by the Examiner as corresponding to the visual effect layer and the color layer of the claimed invention, respectively.

In the appeal against the final rejection, the Trial Board dismissed the applicant’s appeal for lack of inventive step based on the same prior art reference.  However, unlike the Examiner, the Trial Board read that the ink composition layer and the intermediate layer disclosed in the prior art reference, rather than the intermediate layer and the back layer, corresponded respectively to the visual effect layer and the color layer of the claimed invention.  The applicant appealed to the IP High Court.

▶Legal Framework and Issue

Under the Korean Patent Act (“KPA”), when a new ground for rejection is raised, an applicant must be given an opportunity to submit arguments and amendments in response thereto. This requirement also applies mutatis mutandis in the appeal proceedings before the Trial Board (Articles 63(1) and 170 of the KPA).

The key issue in this case was whether a new ground for rejection arises where the Trial Board relies upon the same prior art reference cited during the examination proceedings, but interprets same materially differently. 

▶IP High Court Decision

The IP High Court overturned the Trial Board decision, based on the following reasoning. 

The IP High Court stated that a mere change, during the appeal stage, in identifying the correspondence between the claim elements and the disclosures of the prior art from the examination stage does not automatically give rise to a new ground of rejection.

However, the Court noted that, where such change pertains to the distinguishing features between the claimed invention and the prior art reference, thereby causing a material change in the applicant’s argument and amendment strategies, such change may constitute a new ground for rejection. 

Based on the above reasoning, the Court concluded that the Trial Board decision was in error because it dismissed the Plaintiff’s appeal based on a new ground for rejection that materially differed from the ground raised during examination, without providing the Plaintiff with an opportunity to be heard.