Is a power of attorney required for a Korean patent application?

Sangwook Je, Partner · Published 26 October 2026

Last verified 9 October 2026

Power of attorney rules at a glance

As of October 2026.

Foreign applicants must use an agent, and the agent’s authority is proved in writing

A foreign applicant with no domicile or place of business in Korea can file a patent application only through a Korean agent. Article 5(1) of the Patent Act calls a person with no domicile or place of business in Korea an “overseas resident”. An overseas resident can take patent procedures only through a “patent administrator”, except when the overseas resident is staying in Korea. [1] When the overseas resident is a corporation, the exception is when its representative is staying in Korea. [1] A patent administrator is an agent who has an domicile or place of business in Korea. [1]

Application documents filed by an overseas resident without a patent administrator are not treated as lawful application documents (Enforcement Rules, Art. 11(1), subparagraph 6). [2] The Minister of Intellectual Property first sends a document stating the reason for return and an explanation period (Art. 11(2)). [2] The Patent Examination Guidelines (특허·실용신안 심사기준) state that in this case the defect cannot be cured by an amendment that appoints a patent administrator afterwards. [3]

The authority of an agent must be proved in writing (Patent Act, Art. 7). [1] The agents under Article 7 of the Patent Act include a patent administrator. [1] Article 5(1) of the Enforcement Rules fixes that writing as the power of attorney in Form 1. [2] The attachments to the written patent application also include “one copy of the document proving the authority of the agent” (Enforcement Rules, Art. 21(1), subparagraph 2). [2]

When the agent files the written patent application with the power of attorney attached, no separate notification of appointment of an agent is made (Enforcement Rules, Art. 5(2), proviso). [2]

The office that receives the power of attorney is the Ministry of Intellectual Property (MOIP, 지식재산처). Before the amendment of 1 October 2025, the legislation read “Commissioner of the Korean Intellectual Property Office” (특허청장). [2]

A signature or seal is enough, and a scanned copy can be filed

The power of attorney is a form that the principal signs or seals. Form 1 has the following fields. [2]

If the principal has no applicant code yet, the name is entered in Korean and in English, together with other details. [2]

Form 1 and Article 5 of the Enforcement Rules have no wording that requires notarization, authentication or consular legalization. [2] The signature field of the form reads “signature or seal of the principal”. [2]

However, the Minister of Intellectual Property can require documents when a specific check of the person taking the procedure is found necessary (Enforcement Rules, Art. 8(1)). [2] These documents include a certificate of nationality of a foreigner and a notarial certificate of the signature. [2] For a foreigner, they also include a certificate from a public office of the home country that the person signed in person. [2] The Minister must notify the name of the document and the reason, and must give an opportunity to explain (Art. 8(4)). [2] Application documents for which the required document is not filed within the explanation period, without a justified explanation, are subject to return (Enforcement Rules, Art. 11(1), subparagraph 14). [2]

The paper original of the power of attorney does not need to be sent. The instructions for the form state that a signed or sealed power of attorney can be scanned and filed as an attachment to another form. [2] A person who files documents electronically can file attachments as electronic images (Enforcement Rules, Art. 3-2(1)). [2] If the image is hard to read and a check is found necessary, the Minister of Intellectual Property can order the paper document to be filed (Art. 3-2(2)). [2]

The power of attorney can be written in a foreign language. A Korean translation must be attached to a power of attorney written in a foreign language (Enforcement Rules, Art. 4(1), subparagraph 3, and Art. 4(2)). [2]

Eight acts, including withdrawal and abandonment of the application, must be stated separately

An agent can perform the eight acts in Article 6 of the Patent Act only with special authorization. [1] The same applies to a patent administrator. [1]

The priority claim in subparagraph 6 is a priority claim based on an earlier Korean patent application or utility model application (Patent Act, Art. 55(1)). [1] The trial in subparagraph 7 is an appeal against a decision of rejection (decision to reject a patent application) or against a decision to reject registration of an extension of the term of a patent (Patent Act, Art. 132-17). [1]

The Examination Guidelines treat a power of attorney that states the matters delegated as “all matters concerning ooo” (ooo에 관한 일체의 건) as not including the acts in Article 6 of the Patent Act. [3] On the other hand, the instructions for Form 1 state that the matters delegated are in principle written collectively, and give “all procedures concerning a patent application” as an example. [2] The same instructions give “withdrawal and abandonment of a patent application” and “appointment of a sub-agent” as examples of specifying matters one by one. [2]

The list of matters in the general power of attorney also keeps the two apart. In the list in Form 3, “all procedures concerning a patent application” is A01. Abandonment of a patent application (A04), withdrawal of a patent application (A05), a priority claim under Article 55(1) of the Patent Act (A10) and appointment of a sub-agent (A12) are separate codes. [2]

The Examination Guidelines state that the earlier application must be identified when special authorization for a domestic priority claim is indicated. [3]

A missing power of attorney leads to a request for amendment, and filing it in time keeps the procedure

Documents filed by an agent without a power of attorney are not invalid at once. The agent receives a request for amendment. The Examination Guidelines treat a case in which no document proving the authority of the agent is attached as unauthorized representation. [3] In that case MOIP requests an amendment so that a correct power of attorney is filed. [3] When a correct power of attorney is filed, the principal is treated as having ratified the procedure. [3]

The amendment period under Article 46 of the Patent Act is set at up to 1 month (Enforcement Rules, Art. 16(1), subparagraph 1). [2] A period set by the Minister of Intellectual Property can be extended on request (Patent Act, Art. 15(2)). [1] The amendment is made by attaching the document proving the authority of the agent to the written amendment (Enforcement Rules, Art. 13). [2]

Ratification has retroactive effect. A procedure taken by a person whose delegation of authority is defective takes effect retroactively from the time of the act when it is ratified (Patent Act, Art. 7-2). [1] The Examination Guidelines also state that a procedure taken by an unauthorized agent takes effect, through ratification, back to the time of the original act. [3]

The filing date of a patent application is the date on which the written patent application, with the specification and any necessary drawings attached, reaches the Minister of Intellectual Property (Patent Act, Art. 42-2(1)). [1] Therefore, if a correct power of attorney is filed within the amendment period, the application filed by the agent is effective from the time the written application was filed (Patent Act, Art. 7-2). In this case the filing date is the date on which the written application arrived (Patent Act, Art. 42-2(1)). Application documents filed directly by an overseas resident without a patent administrator are different, because they are subject to return (Enforcement Rules, Art. 11(1), subparagraph 6). [2]

If no amendment is made within the designated period (specified period), the Minister of Intellectual Property can invalidate the procedure (Patent Act, Art. 16(1)). [1] The Examination Guidelines also state that the procedure taken by the agent is invalidated if there is no ratification. [3] If good cause for missing the period is recognized, a request can be made to revoke the invalidation of the procedure. The time limit for the request is 2 months from the date on which the reason ceased to exist, and no request can be made after 1 year from the expiration date of the designated period (Patent Act, Art. 16(2)). [1]

The Examination Guidelines also treat a case in which the name of the principal on the power of attorney is different as unauthorized representation. [3] An amendment is also requested when the entries in the written application and in the power of attorney do not match. [3]

A document that is not filed together with the written application cannot be listed in the attachments field of the written application. [2]

With a registered general power of attorney, no power of attorney is filed for each case

An applicant who entrusts several cases to the same agent files the power of attorney only once, by registration of a general power of attorney. A general power of attorney delegates present and future cases without specifying them in advance (Enforcement Rules, Art. 5-2(1)). [2]

1. The agent explains the general power of attorney and obtains the signature or seal of the person delegating on the general power of attorney (포괄위임장). [2]
2. The application for registration of a general power of attorney in Form 3 is filed with the Minister of Intellectual Property, with the general power of attorney attached. [2]
3. The Minister of Intellectual Property assigns a general power of attorney registration number and notifies it (Art. 5-2(2)). [2]
4. The agent enters the general power of attorney registration number in documents filed afterwards (Art. 5-2(3)). [2]

When an agent with a registered general power of attorney takes a procedure within its scope, the document proving the authority of the agent can be omitted (Enforcement Rules, Art. 10(3), subparagraph 2). [2]

In the general power of attorney, the matters to be delegated are chosen from a list of matters with code numbers. [2] The general power of attorney has a field for “confirmation of the explanation of the general power of attorney”, which is completed with the name and a signature or seal. [2] A general power of attorney is filed online by one of two methods (Enforcement Rules, Art. 5-2(5)). [2] One method is to sign the general power of attorney electronically and file it as an electronic document. The other is to enter an authentication number sent to a mobile phone and attach an image of the signed or sealed general power of attorney. [2]

A general power of attorney can be restricted for a single case or revoked. To restrict the invoking of the general power of attorney for a specific case, a notification in Form 2 is filed (Enforcement Rules, Art. 5-3). [2] To revoke the general power of attorney, a revocation in Form 3 is filed (Enforcement Rules, Art. 5-4). [2]

Applicants without a registered general power of attorney also have rules that allow omission. When two or more procedures are taken at the same time, the original can be filed in one case and copies in the others (Enforcement Rules, Art. 10(1)). [2] If the content is the same as a power of attorney already filed, a statement in the attachments field that it is invoked can replace the power of attorney (Art. 10(2)). [2] The power of attorney can also be omitted when an agent whose appointment has been notified takes a procedure within the scope of the matters delegated (Art. 10(3), subparagraph 1). [2]

There is no official fee for filing a power of attorney or for registration of a general power of attorney. No provision of the Regulation on the Collection of Patent Fees, etc. (특허료 등의 징수규칙) sets a fee item for either. [4]

In the PCT national phase, the appointment of a patent administrator has a time limit

In the PCT national phase, an overseas resident who has filed the Korean translation must appoint a patent administrator and notify the appointment within 2 months from the reference date (기준일). Without the notification, the international patent application is deemed withdrawn (Patent Act, Art. 206(3)). [1]

An overseas resident who is the applicant of an international patent application can take procedures without a patent administrator until the reference date (Patent Act, Art. 206(1)). [1] An overseas resident who has filed the Korean translation must then appoint a patent administrator and notify the appointment within a prescribed period (Art. 206(2)). [1] That period is 2 months from the reference date (Enforcement Rules, Art. 116). [2]

The reference date is the expiration date of the period for submitting domestic documents (국내서면제출기간). If the applicant has requested examination within that period, the date of the request is the reference date (Patent Act, Art. 201(5)). [1] The period for submitting domestic documents is 2 years and 7 months from the priority date (Patent Act, Art. 201(1)). [1] The applicant can state a request to extend the period for filing the Korean translation in the document under Article 203(1) of the Patent Act (Patent Act, Art. 201(1), proviso). [1] In this case the period for submitting domestic documents that fixes the reference date is the extended period for filing the Korean translation (Patent Act, Art. 201(3) and 201(5)). [1] The extended period runs until the day that is 1 month from the expiration date of the period for submitting domestic documents (Patent Act, Art. 201(1), proviso). [1]

When the agent files the document under Article 203 of the Patent Act with the power of attorney attached, no separate notification of appointment is made (Enforcement Rules, Art. 5(2), proviso). [2] This is the document that the applicant of an international patent application files within the period for submitting domestic documents (Patent Act, Art. 203(1)). [1]

A new power of attorney is filed when the agent or the applicant changes after filing

When a new agent is appointed after filing, a notification is filed with the power of attorney attached. The Examination Guidelines state that a notification with the power of attorney attached must be filed when an agent is appointed or changed during the procedure. [3] Notification of appointment of an agent, dismissal, a change in the content of the authority and resignation are made with the notification in Form 2 (Enforcement Rules, Art. 5(3) and 5(5) to 5(7)). [2]

The Examination Guidelines deal separately with a case in which only a power of attorney is attached to an intermediate document such as a written argument. In this case the authority of the agent is recognized only for that intermediate procedure. [3] If the same agent is to take later procedures as well, a separate notification of appointment must be made. [3]

When the applicant has changed, a power of attorney from the new applicant is needed. The Examination Guidelines deal with a case in which the previous agent continues the procedure in an application with a change of applicant. In that case a notification of appointment of an agent must be filed with the power of attorney of the successor attached. [3]

The authority of the agent does not end when a corporation that is the applicant ceases to exist through a merger (Patent Act, Art. 8, subparagraph 2). [1]

In the amended Patent Act (Act No. 21955) that enters into force on 16 March 2027, the text of the Patent Act provisions used in this article is the same. [6]

How Korea differs

In the United States, when a registered patent practitioner signs a paper in a representative capacity, the signature is the indication of authority. 37 CFR 1.34 treats the signature of a registered practitioner as a representation that the practitioner is authorized to represent that party. [5] The same section provides that further proof of authority can be required. [5]

Korea has no provision that recognizes the authority of an agent on the agent’s signature alone. The authority must be proved in writing, and the attachments to the written application include the document proving the authority of the agent. [1][2]

What applicants should do

• In general, when a Korean application is entrusted for the first time, we suggest sending a scanned copy of the signed power of attorney together with the filing instructions. If the power of attorney is late, there is one more task: responding to a request for amendment.
• If several applications are planned in Korea, we suggest registering a general power of attorney together with the first case.
• For the matters delegated, we suggest not writing only “all procedures” but stating the acts in Article 6 of the Patent Act separately. These include withdrawal and abandonment of the application, a priority claim under Article 55(1) of the Patent Act, and a petition for trial against a decision of rejection.
• We suggest writing the applicant’s name in the power of attorney in the same way as in the written application. A difference between the entries in the written application and in the power of attorney is a ground for a request for amendment.
• For the PCT national phase, we suggest filing the power of attorney together with the entry document. If the time limit for notifying the appointment of a patent administrator is missed, the application is deemed withdrawn.
• If an assignment of the application is planned, we suggest preparing a power of attorney in the name of the successor in advance.

The scope of delegation and the time limits in an individual case should be confirmed with the Korean agent.

FAQ

Does a power of attorney filed with the Korean Ministry of Intellectual Property need notarization or an apostille?

The power of attorney form and Article 5 of the Enforcement Rules have no wording that requires notarization or authentication. [2] However, the Minister of Intellectual Property can require documents such as a notarial certificate of the signature when a specific check is found necessary (Enforcement Rules, Art. 8(1)). [2]

Does the original power of attorney have to be sent by post?

A signed or sealed power of attorney can be scanned and filed as an attachment. [2] If the image is hard to read and a check is found necessary, the paper document can be ordered to be filed (Enforcement Rules, Art. 3-2(2)). [2]

What happens if the power of attorney is not ready by the filing date?

If there is no document proving the authority of the agent, a request for amendment is issued. [3] The amendment period under Article 46 of the Patent Act is set at up to 1 month. [2] If a correct power of attorney is filed within the period, the principal is treated as having ratified the procedure. [3]

Does a new power of attorney have to be signed for each case?

With a registered general power of attorney, no power of attorney is filed for cases within its scope (Enforcement Rules, Art. 10(3), subparagraph 2). [2] The agent enters the general power of attorney registration number in the documents. [2]

Is there an official fee for filing a power of attorney or for registration of a general power of attorney?

No. The Fee Regulation has no provision that sets a fee item for either. [4]

How DEFINE IP Law Firm handles this

DEFINE IP Law Firm checks the matters delegated and the applicant’s name in the power of attorney at the stage of accepting a case. We check again whether the acts in Article 6 of the Patent Act are stated in the power of attorney before taking a procedure such as withdrawal, abandonment or a petition for trial. For questions about a Korean application or entry into the Korean national phase, please write to contact@defineip.kr.

Sources

1. Ministry of Intellectual Property (지식재산처), Patent Act (특허법), Act No. 21134, in force from 11 November 2025. Articles 5, 6, 7, 7-2, 8, 15, 16, 42-2, 46, 55, 132-17, 201, 203 and 206. https://www.law.go.kr/법령/특허법 (verified 2026-10-09)
2. Ministry of Intellectual Property (지식재산처), Enforcement Rules of the Patent Act (특허법 시행규칙), Prime Ministerial Decree No. 2115, in force from 14 May 2026. Articles 3-2, 4, 5, 5-2 to 5-4, 8, 10, 11, 13, 16, 21 and 116, Form 1, Form 3 and Form 14. https://www.law.go.kr/법령/특허법시행규칙 (verified 2026-10-09)
3. Ministry of Intellectual Property (지식재산처), Patent Examination Guidelines (특허·실용신안 심사기준), MOIP Established Rule No. 7, in force from 13 March 2026. Part 1, Chapter 1, 3.3; Chapter 2, 4., 5., 6.1 and 6.2. https://www.law.go.kr/행정규칙/특허·실용신안심사기준 (verified 2026-10-09)
4. Ministry of Intellectual Property (지식재산처), Regulation on the Collection of Patent Fees, etc. (특허료 등의 징수규칙), Prime Ministerial Decree No. 2098, in force from 27 February 2026. https://www.law.go.kr/법령/특허료등의징수규칙 (verified 2026-10-09)
5. United States Patent and Trademark Office (USPTO), 37 CFR 1.32 and 1.34, eCFR as updated through 26 August 2026. https://www.ecfr.gov/current/title-37/section-1.34 (verified 2026-10-09)
6. Ministry of Intellectual Property (지식재산처), Patent Act (특허법), Act No. 21955, promulgated on 15 September 2026, to enter into force on 16 March 2027. https://www.law.go.kr/법령/특허법 (verified 2026-10-09)