How to File a Patent in South Korea with KIPO

Filing a patent in South Korea means dealing with the Korean Intellectual Property Office (KIPO), one of the most active patent authorities in the world and a member of the major international IP treaties. The mechanics are broadly familiar to anyone who has filed elsewhere, but Korea has features that catch applicants out: it is strictly first-to-file, it is examined on a Korean-language specification, foreign applicants without a domestic address must act through a local representative, and, importantly, it treats the request for examination as a separate step that you must take deliberately within a set period or the application lapses. This guide walks through the route from filing to grant, the need to pay annuities, and the two main ways foreign applicants reach Korea: the Patent Cooperation Treaty (PCT) national phase and the Paris Convention priority route. For the wider picture of protecting an invention in Korea, see our South Korea patents overview.

This is general information rather than legal advice. Korean patent practice is procedural and unforgiving on deadlines, and almost all foreign applicants act through a Korean patent attorney. Treat the timelines below as orientation and confirm the current periods and fees with KIPO or local counsel before you act.

What you can protect, and the core requirements

Korea grants patents for inventions, understood in essence as the highly advanced creation of technical ideas using the laws of nature. To be patentable, an invention generally needs to satisfy three substantive conditions, which KIPO assesses during examination. Patents are not the only form of protection: some outputs, such as software code and written or artistic works, are protected automatically by copyright under the Berne Convention without registration, which is a distinct mechanism from the patent route, so do not assume a patent is the only way to protect a given result. Which right fits your situation is a point to discuss with counsel.

The first requirement is novelty. The invention must not already form part of the state of the art, meaning it must not have been publicly known, publicly worked, or described in a published document before the filing date (or the priority date, if you claim priority). Korea applies an absolute (worldwide) novelty standard, so a disclosure you made yourself, anywhere, can defeat novelty. Korea does provide a grace period for certain disclosures by the applicant, but the conditions and the length of that period are specific and easy to get wrong, so confirm the current position with counsel rather than rely on it.

The second is inventive step. Even if the invention is new, it must not have been something a person skilled in the relevant field could have easily arrived at from what was already known. This requirement most often determines whether a patent is granted.

The third is industrial applicability. The invention must be capable of industrial use. As in many systems, certain methods of treating the human body by surgery, therapy or diagnosis are generally treated differently from products such as medicines or devices, and the boundaries here are technical and jurisdiction-specific, so confirm the current position with Korean counsel rather than treat this as a flat universal rule.

The specification and claims

The substance of a Korean application is the specification: a written description of the invention, one or more claims defining the scope of protection sought, any drawings needed to understand it, and an abstract. The description must disclose the invention clearly and completely enough for a skilled person to carry it out, and the claims must be supported by the description. Weak disclosure or unclear claims are common grounds for objection, and they are awkward to cure later because amendments generally cannot add new matter beyond the original disclosure.

The claims do the legal work. They define what is protected and what a competitor must avoid, so claim drafting is where most of the value (and most of the risk) sits. This is a strong reason to use an attorney who understands both the technology and Korean claim practice rather than treating the application as a form-filling exercise.

First-to-file: the date is everything

Korea is a first-to-file jurisdiction. Where two applicants independently arrive at the same invention, the one who files first at KIPO has priority, regardless of who invented it first. There is no general mechanism for a later inventor to displace an earlier filer by proving earlier invention.

The practical consequence is simple: file early, and file before you disclose. Public disclosure before filing can defeat your own application on novelty grounds, and while a grace period may help in some situations, it is far safer to file first. First-to-file also makes priority dates valuable, which is where the Paris Convention and PCT routes below come in.

Filing language and translation quality

A Korean patent application is ultimately examined on a Korean-language specification, including the description, claims and abstract, with any drawings. Foreign applicants therefore need a Korean translation prepared, and translation quality matters: ambiguities or errors introduced in translation can narrow your claims or create objections that are awkward to fix later, given the limits on adding new matter.

Korea does provide mechanisms that can let you secure a filing date before a full Korean specification is ready, including, in defined circumstances, filing in a foreign language and submitting the Korean translation within a prescribed later period. The availability, exact deadlines and consequences of missing them are specific and have changed over time, so treat this as a confirm-with-counsel point rather than a fixed rule. The safe planning assumption is that you will need a careful Korean translation, prepared or reviewed by someone who understands both the technology and Korean claim drafting.

The local-representative requirement

A foreign applicant with no address or place of business in Korea must, under Korean practice, act through an appointed domestic representative (a patent administrator) to conduct proceedings and receive official correspondence from KIPO. This is a KIPO-specific procedural requirement and is distinct from the practical decision to engage a patent attorney, although in practice the representative is commonly a Korean patent attorney. Confirm the current position and exactly who must be appointed with local counsel, and engage them early, as this is effectively necessary for most foreign filers.

On filing you pay official fees, and the cost of obtaining a Korean patent is driven by several factors rather than a single number: the official filing fee, the separate examination-request fee discussed below, the cost of translation into Korean, attorney fees, the number of claims, and renewal (annuity) fees once granted. Because fees change and depend on the specifics of your application, official fees apply and you should confirm the current amount with KIPO or local counsel rather than rely on any figure quoted second-hand.

The separate request for examination

This is the step that most distinguishes Korean practice from some other systems and the one most likely to trip up an unwary applicant. Filing an application at KIPO does not by itself put it in the examination queue. Substantive examination begins only when someone files a separate request for examination and pays the associated fee.

Crucially, that request must be made within a set statutory period running from the filing date. If the request is not filed within the applicable period, the application is treated as withdrawn and the opportunity to obtain a patent on it is lost. Because this period is fixed by statute and is one of the most dangerous deadlines in the Korean process, do not rely on a remembered figure: confirm the current period with KIPO or your Korean attorney and diary it carefully, including for any national-phase entry. Note too that, under Korean law, examination can be requested by parties other than the applicant in defined circumstances, so the timing of examination is not always entirely within your control.

Publication, examination and office actions

Korean applications are, in the normal course, published (laid open) after a defined period from the filing or priority date, which puts the application into the public domain as prior art and can give the applicant certain provisional rights against use of the invention in the interim, subject to conditions. Treat the exact period and the scope of any provisional protection as confirm-with-counsel, since they are statute-specific.

Once examination is requested, a KIPO examiner reviews the application against the patentability requirements and for formal and clarity issues. If the examiner identifies problems, KIPO issues a notification of grounds for rejection (an office action), to which the applicant can respond by argument and by amending the claims or description, within the limits on adding new matter. There is usually more than one opportunity to respond, but the response periods are fixed and missing them has consequences, so they should be diarised and confirmed with counsel.

Grant, and paying annuities to maintain the patent

If the examiner is satisfied, KIPO issues a decision to grant, and the patent is registered and published once the registration fee is paid. If the examiner maintains a rejection, the applicant can pursue the matter through KIPO's trial procedures, which run before the Intellectual Property Trial and Appeal Board (IPTAB), a quasi-judicial body within KIPO, and from there on appeal to the specialist court (currently styled the Intellectual Property High Court, also known as the Patent Court of Korea) and ultimately the Supreme Court. The exact route and the names of these bodies have changed over time, so confirm the current structure with counsel. Korea also provides mechanisms for third parties to challenge patents, so grant is not necessarily the end of the contest.

A granted Korean patent runs for a defined term from the filing date, subject to payment of annuities (renewal fees), with the possibility of term extension in limited cases, notably where a regulatory approval was required before the invention could be worked. Annuities must be paid to keep the patent in force; miss them and the patent can lapse, so maintenance is an ongoing diary task rather than a one-off. Treat the exact term, the annuity schedule and any extension rules as confirm-with-counsel, since they are statute-specific. For a faster, lighter alternative for certain inventions, particularly those concerning the shape or construction of an article, see our South Korea utility models guide, which covers how that right sits alongside the patent route.

Reaching Korea from abroad: PCT and Paris priority

Most foreign applicants reach Korea by one of two international routes, and the choice usually depends on how many countries you are targeting and your timing.

The PCT national-phase route is common where you want patent protection in several countries. You file a single international application under the PCT, which preserves an effective filing date across all member states, then later enter the national phase in each country you choose, including Korea, by meeting that country's requirements (translation into Korean, national fees and any local formalities) within the prescribed national-phase deadline. Entering the Korean national phase still requires you to make the separate request for examination within the applicable period, so the examination deadline does not disappear simply because you arrived via the PCT. For how the international system works generally, see our PCT guide.

The Paris Convention priority route suits applicants filing directly in a smaller number of countries. If you file a first application in one Paris Convention country, you can file corresponding applications in Korea within the Paris priority period (commonly around twelve months for patents, but confirm the current period and its precise calculation with KIPO or counsel) and have those Korean applications treated, for the purpose of assessing prior art and intervening filings, as if filed on your original priority date. The two routes are not mutually exclusive; a PCT application itself commonly claims Paris priority from an earlier national filing.

Where to get this right

Korean patent prosecution rewards early filing, accurate Korean drafting, and disciplined diary management of several deadlines in particular: the priority or national-phase entry deadline, the separate request for examination, and the ongoing annuities once a patent is granted. Getting any of these wrong can be fatal to the application or the patent, and many such slips are unrecoverable.

IPEnvoy is not a law firm and does not provide legal advice. This page is general information to help you understand the process, not a substitute for advice on your specific invention. Confirm the current position with KIPO's official website and a qualified Korean IP professional before you act. IPEnvoy can connect you with vetted local counsel in Korea and coordinate filings across multiple jurisdictions where you need protection in more than one market.