Overview of two key patent cases in South Korea

The Korean Supreme Court recently rendered two noteworthy decisions that underscore the Court's commitment to upholding and clarifying patent rights in South Korea.

The applicant filed a patent application without claiming the benefit of a grace period based on the applicant’s own prior disclosure. As a result, the patent application was rejected for lack of novelty and inventiveness due to the prior publication.

Subsequently, the applicant filed a divisional application while claiming the benefit of a grace period at the time of filing the divisional. However, the Trial Board and the Intellectual Property High Court (previously Patent Court of Korea) both decided that the grace period benefit could not be claimed for the divisional since the applicant failed to claim the grace period at the time of filing the parent application.

On appeal, the Korean Supreme Court reversed the lower court’s decision and held that even if the applicant failed to claim the grace period benefit when filing the parent application, the applicant may still claim and benefit from the grace period as long as the parent application was filed within 12 months from the self-disclosure.

The applicant filed a patent application titled: “Method for wiring a sequence control circuit” (“the parent application”) on December 23, 2014. While it was within the grace period of 12 months from the date of the applicant’s own prior disclosure, the applicant did not claim the benefit of a grace period under Article 30(1) of the Korean Patent Act (KPA) and the KIPO examiner rejected the parent application for lack of novelty and inventiveness, based on the applicant’s own paper published in August 2014.

The applicant then filed a divisional application on August 30, 2016, while claiming the benefit of a grace period based on the earlier-published paper.

The KIPO examiner, however, denied the applicant’s request for the grace period benefit and rejected the divisional application for lack of novelty and inventiveness, based on the prior publication. Although the applicant appealed before the Trial Board and subsequently filed a legal action for judicial review before the IP High Court, both tribunals concluded that the request for the grace period for the divisional application was improper since no such request had been made at the time of filing the parent application.

In order to claim the benefit of the grace period, Article 30(1) of the KPA stipulates that for assessing the novelty and inventiveness of a patent application, public disclosure of an invention made by a person having a right to obtain a patent thereon shall not be regarded as prior art, provided the patent application is filed within the grace period of 12 months from the disclosure date. Article 30(2) further stipulates that an applicant seeking to invoke the grace period clause must state this when filing the patent application and submit evidentiary documents to the KIPO within 30 days of filing the patent application.

In addition, Article 30(3), enacted on January 28, 2015 and applicable for patent applications filed on or after July 29, 2015, introduced a way for the claiming of the benefit of a grace period even after the filing date of a patent application under certain conditions. Specifically, Article 30(3) stipulates that, subject to a fee, a document stating the intent to invoke the grace period clause and evidentiary materials in support thereof may be submitted within one of the following periods:

• During the period of filing a voluntary amendment or submitting a response to an office action; or

• Within three months of receiving a certified copy of either a notice of allowance or the Trial Board’s decision reversing the examiner’s rejection of the patent application.

However, Article 52(2) of the KPA stipulates that, although a divisional application shall be deemed to have been filed when the parent application was filed, the effect of this statutory presumption of retroactive filing shall not be given for the purpose of applying Article 30(2), mentioned above.

The Intellectual Property High Court decided that a divisional application is not eligible for a grace period if the request for the grace period was not made at the time of filing its parent application, because:

• If such claiming in a divisional application is allowed, Article 30(2) of the KPA would be easily circumvented or become meaningless; and

• Article 30(3), which provides an opportunity to belatedly claim the benefit of a grace period, may be invoked for a patent application filed on or after July 29, 2015, and is not applicable to the subject parent application, which had been filed prior to the enactment of Article 30(3).

On appeal, the Supreme Court overturned the lower court decision. It ruled that even though the grace period had not been claimed when filing the parent application, in view of the rationale underlying the provisions of a grace period and a divisional application, it is proper to confer the divisional application the benefit of a grace period, provided that the claim for the grace period benefit is timely made when filing the divisional application.

In accordance with the Supreme Court’s decision, the KIPO revised its examination guidelines on March 22, 2023 to recognise the applicant’s ability to claim a grace period when filing a divisional application, where the parent application was filed within the period of 12 months from the applicant’s prior disclosure.

In a case dated January 14, 2022, the Supreme Court reversed the Intellectual Property High Court’s decision, holding that the scope of protection of a product patent claim is not confined to what may be produced by the method of manufacture specifically disclosed in the patent specification.

The patentee brought a scope confirmation petition before the Trial Board, seeking to obtain a ruling that the product made and sold by the respondent fell within the scope of claim 1 of Korean Patent No. 0815579.

Claim 1 of the patent is directed to a three-dimensional multilayer fabric comprising a surface layer, a backing layer and an intermediate layer that connects the surface layer and the backing layer. The claim has the limitation that intermediate warp threads are woven without interlacing with weft threads.

The description and drawings purporting to define the respondent’s product, submitted for review by the patentee, presented a specific configuration of a product produced by the respondent, which corresponded to the elements of claim 1.

The Trial Board sided with the patentee and concluded that the respondent’s product described and presented by the petitioner for review fell within the scope of claim 1 of the patent since it included all of the elements recited in claim 1.

On appeal, however, the respondent argued that the manufacturing method actually employed by the respondent differed from the process described and presented by the petitioner.

Considering the respondent’s argument, the Intellectual Property High Court overturned the Trial Board's ruling. This was based on the reasoning that, as a matter of principle, what is described in the scope confirmation petition, as presented by the patentee-petitioner, should be considered as the proper subject matter for comparative review and scope confirmation. However, if the manufacturing process asserted to be functional by the respondent, in fact, is not identical to the method described in the petition or given in the patent specification, the scope confirmation petition has no merit and should be dismissed.

In reversing the decision of the IP High Court, the Supreme Court determined that the subject matter of claim 1 should be construed as a three-dimensional multilayer fabric as a product per se. Therefore, the scope of claim 1 should not be limited to what may be made by the specific manufacturing method exemplified in the patent specification or described in the petition.