Changes to South Korea’s Patent Term Extension System
The landscape of patent term extensions (PTE) in South Korea is on the cusp of significant transformation. With pivotal amendments to the PTE regime set to take effect on July 22, 2025, stakeholders in the pharmaceutical and agrochemical sectors must prepare for a new era of regulatory complexity and strategic decision-making. These changes will directly impact how innovators protect their investments in new chemical entities and navigate the intricate interplay between patent rights and regulatory approvals. In this post, we will analyze the forthcoming amendments, examine their practical implications, and provide guidance on optimizing patent strategies considering South Korea’s evolving PTE framework. Whether you are a patent attorney, in-house counsel, or regulatory affairs professional, understanding these amendments is essential for safeguarding exclusivity and maximizing the value of your intellectual property assets in this critical jurisdiction.
Background on South Korea’s PTE System
Under South Korea’s PTE system, when a patent has issued, but cannot be practiced until a product is approved by the Ministry of Food and Drug Safety (MFDS), the term of such a patent can be extended once for a period of up to 5 years.
Patents eligible for PTE:
1. Require (a) approval or registration under another Act to be practiced (e.g., the Pharmaceutical Affairs Act for medicines or the Agrochemical Management Act for agrochemicals); and (b) long-term efficacy/safety experiments are required to receive approval or registration according to Article 7 of the Enforcement Decree of the Korean Patent Act (KPA); and
2. In the case of medicines, they are limited to medicines containing a new chemical entity as the active ingredient, which is receiving marketing approval for the first time. In other words, PTE is available only for the first approval of a new chemical entity. A “new chemical entity” is defined as a novel chemical structure of an active portion of a molecule that demonstrates pharmaceutical activity.
An application for PTE must be filed within three months from the date of marketing authorization (e.g., approval), but no later than 6 months prior to the expiration date of the patent to be extended.
Revisions to the PTE system
Currently, for multiple approvals, the PTE system in South Korea provides that:
1. PTE is granted only once (e.g., a single time) for each patent;
2. If there are multiple approvals for multiple active ingredients covered by a single patent, PTE is granted only once (e.g., a single time) for a patent; and
3. If there are multiple approvals for the same active ingredient, PTE is granted only once, for a single patent, and for the first approval. Consequently, no further PTEs would be granted for subsequent approvals.
If multiple patents are involved in a single approval, there is no limit on the number of patents eligible for PTE.
However, the Amendments change this to limit the number of patents that can be extended by on a single approval to only one patent. Thereupon, a patent owner must select a single (e.g., one) patent to receive the PTE.
Additionally, under the current PTE system, the length of extension is calculated as the sum of: (a) the time taken for domestic clinical testing; and (b) the time taken for regulatory approval minus (i) any time occurring before the patent issues; and/or (ii) any delay attributable to the marketing approval holder (e.g., the time need to supplement documents, etc.). However, the length of the extension is subject to the caveat that the maximum PTE that can be awarded is 5 years from the expiration date of the patent (e.g., a 5-year cap). This differs from both the U.S. and Europe, which require that the length of any PTE not exceed 14 years (U.S.) or 15 years (Europe) from the date of marketing approval, with a 14-year cap or a 15-year cap.
The Amendments introduce a second caveat to the length of extension, namely, a 14-year cap like that in the U.S. Beginning on July 22, 2025, like the U.S., the length of PTE that can be awarded in South Korea will be subject to two caveats: (1) the length of the extension cannot exceed 5-years from the expiration date of the patent (e.g., a 5-year cap); or (2) 14-years from the date of marketing approval for a product (e.g., a 14-year cap), whichever is earlier.
Strategic considerations
If a patent application covers multiple drug candidates, Applicants should file one or more divisional applications to ensure that a PTE can be requested for each potential active ingredient.
To maximize PTE, consider requesting an expedited examination, such as through the Patent Prosecution Highway, to expedite issuance. Since days that occur after the issuance of a patent are relevant when determining the time taken for the regulatory review period, this approach can be beneficial.
Because of these Amendments, patent owners need to carefully consider which patent to extend based on the following:
1. Which patent can ensure the longest patent term given the 14-year cap?
2. Which patent is the strongest or most vulnerable to a validity challenge?
3. What patent is the most straightforward to enforce?
4. The subject matter (e.g., product versus method claim) and the scope of the patent.
Final thoughts
The upcoming amendments to South Korea’s PTE system mark a significant shift toward harmonization with international standards, particularly those of the United States and the European Union. By introducing a dual cap-limiting extension to the earlier of five years from patent expiry or fourteen years from marketing approval, South Korea is both tightening and clarifying the boundaries of post-approval exclusivity. Patent owners must now approach PTE strategy with heightened diligence, carefully selecting which patent to extend and considering the broader implications for enforcement, validity, and portfolio management. As the regulatory and patent landscapes continue to converge, proactive planning and tailored legal strategies will be indispensable for maintaining a competitive edge. Staying informed and agile will ensure that innovators can continue to bring life-saving therapies to market while securing the full benefit of their intellectual property rights.
This post was written by Lisa Mueller and Central Intellectual Property Law.