In 2022, the Supreme Court of Korea stated that, if the scope of a claim in a divisional application is included in disclosed content, and the applicant did not assert an exception of public disclosure in the original application due to the claim’s lack of relevance to the disclosed content, it is considered necessary to assert an exception of public disclosure in the divisional application, “even if it was not asserted in the original application.” Accordingly, the Supreme Court's ruling indicated that if proper procedures were followed to assert an exception of public disclosure in the divisional application, even if it was not asserted in the original application, the original application could receive the effects of the exception to public disclosure if it was filed within 12 months from the disclosure date. (Supreme Court Decision 2020Hu11479 decided August 31, 2022)

However, after this decision, there have been ongoing discussions in regard to ① “divisional applications” (Article 52(2) of the Patent Act) allowing for the filing of a new patent application by separating unrejected parts from the original application when the request for trial against a patent rejection decision is dismissed, ② the applicability of the same legal principle to an “amended application” (Article 53 of the Patent Act and Article 10 of the Utility Model Act), which involves filing an application that maintains identity within the original application’s scope by making changes solely to the format, and ③ the permissibility of claiming priority in a divisional application, asserting “domestic priority” (Article 55 of the Patent Act), despite the absence of a priority claim in the original application.

In order to address such issues, the Korean Intellectual Property Office (KIPO) made amendments to the patent examination criteria in March 2023 that would allow the decisions to be applied in an extensive manner including divisional applications, amended applications, and domestic priority in terms of the exception of public disclosure in addition to divisional patent applications as decided by the Supreme Court, so that an applicant can effectively seek protection for the rights of the inventors. In other words, even if an applicant did not assert the exception of public disclosure in the original application, the amended examination criteria now allow for the recognition of the effect of exception of public disclosure if the applicant follows the proper procedures and asserts the exception in a divisional application, amended application, or domestic priority application. However, the examination criterion that if no priority claim was made in the original application, asserting priority in a divisional application is still not recognized remains unchanged. The revised examination criteria should be carefully considered due to their implications since they may significantly impact future patent applications and patent examination practices.