After patent rights are granted and published, the patentee can apply to the Intellectual Property Office (hereinafter “IPO”) for amendment of the patent specification, claims, or drawings in accordance with Article 67 of the Patent Act. In principle, the content of the post-grant amendment (hereinafter “PGA”) shall not exceed the scope disclosed in the specification, claims, or drawings at the time of filing, nor shall it substantially broaden or change the scope of the claims as published. According to Article 68, Paragraph 3 of the same Act, once the PGA has been published after review and approval by the IPO, the amendment takes effect retroactively from the patent filing date. Regarding IPO approval of the PGA, the Patent Act also establishes a public review system referred to as invalidation (hereinafter “PGA invalidation”), whereby any person who believes the PGA to be illegal may file an invalidation request with the IPO pursuant to Article 71 of the Patent Act. Furthermore, Article 82, Paragraph 1 provides that if invalidation is established after examination, the patent rights shall be revoked; Paragraph 3 further stipulates that once the invalidation decision becomes irrevocably finalized, the patent rights shall be deemed to never have existed.

 

In other words, the result of PGA invalidation is the revocation of the patent rights themselves, not merely annulment of the administrative decision approving the amendment. Once patent rights are revoked with irrevocable finality, the effects thereof are deemed null ab initio. Since the result of PGA invalidation leads to revocation of patent rights, how should courts handle other pending litigation related to the concerned patent rights? The Intellectual Property and Commercial Court (hereinafter “IP Court”) expressed views on this issue in Judgment No. 2022-Shin Juan Su-37 rendered on March 27, 2025.

 

In this case, the plaintiff filed an invalidation request with the IPO against Claims 1-5 of the disputed patent on the grounds that these claims lacked novelty due to prior art disclosure. After the IPO ruled the invalidation request unfounded, the plaintiff filed an administrative appeal, followed by this administrative lawsuit with the IP Court (i.e., Administrative Litigation No. 2022-Shin Juan Su-37). During the administrative litigation, the patentee applied to the IPO for PGA of Claim 1 of the disputed patent, which was approved by the IPO. The plaintiff then filed a PGA invalidation request, alleging the amendment was illegal. Although the IPO again ruled the PGA invalidation unfounded, the IP Court subsequently found the amendment illegal in a separate administrative judgment (No. 2024-Shin Juan Su-16) and ordered the IPO to revoke the patent rights for Claim 1. Thereafter, on January 6, 2025, the IPO issued a decision that the invalidation of Claim 1 was established and the patent right should be revoked (*author's note: the Ministry of Economic Affairs' appeal search platform reveals no data for any administrative appeal filed by the patentee against this decision).

 

During the administrative appeal stage of the aforementioned PGA invalidation case, the IP Court ruled to suspend the proceedings of the Administrative Litigation No. 2022-Shin Juan Su-37, and resumed the proceedings after the final determination of the PGA invalidation case. Since Claim 1 of the disputed patent had already been revoked due to the PGA invalidation result at that time, there were differing opinions on how the court should proceed with the subsequent trial of Administrative Litigation No. 2022-Shin Juan Su-37.

 

The IPO argued that although Claim 1 of the disputed patent was revoked based on the result of Administrative Litigation No. 2024-Shin Juan Su-16, the effect of the PGA still existed. Therefore, the IPO contended that the trial should be based on the amended claim.

 

However, the IP Court did not adopt this view. In Judgment No. 2022-Shin Juan Su-37, the court stated that the amendment to Claim 1 of the disputed patent was illegal and thus could not take effect retroactively pursuant to Article 68, Paragraph 3 of the Patent Act. Therefore, the court held that the scope of the disputed patent should be based on Claims 1 to 5 before the amendment. Moreover, the content of Claim 1 in the PGA invalidation case (i.e., the amended Claim 1) differed from that of Claim 1 in the present case (i.e., the pre-amendment Claim 1). Hence, the facts involved in the two litigations were not identical, and the subject matter of the lawsuits also differed. The court should therefore review the validity of amended Claim 1 in the present case. Ultimately, the IP Court ruled that the plaintiff’s cited prior art could prove that Claims 1-5 of the disputed patent lacked novelty, revoked the IPO’s decision that invalidation was unfounded, and ordered the IPO to issue a decision that invalidation of Claims 1-5 was established and the patent rights should be revoked.

 

As mentioned above, the Patent Act establishes “invalidation” as a public review mechanism for “illegal PGA,” and clearly provides that the effect of a successful invalidation is “revocation of the patent rights,” not merely annulment of the “approval of the amendment” decision. The legislative policy is presumably aimed at avoiding repeated changes to the scope of patent rights, which would create undue uncertainty. From the IPO’s argument in Administrative Litigation 2022-Shin Juan Su-37, the IPO's rationale appears to be: since the approval of the amendment was not revoked due to the PGA invalidation, the effect of the amendment still exists, and thus the subject of the trial should be the amended claims. However, the IP Court considered the effect of the amendment to no longer exists, and so determined that the trial should be based on the claims before the amendment, which reflects a different interpretation of the relevant Patent Act provisions. Furthermore, the reasoning of Judgment No. 2022-Shin Juan Su-37 did not address whether there remains a need to review the validity of Claim 1 after it was revoked due to the PGA invalidation. Whether the IPO and the IP Court will maintain their respective views on this issue in the future remains to be seen.