Brief summary
- The deadline for a request for examination of a Korean patent application is three years from the filing date (Patent Act (특허법), Art. 59(2)).
- For a PCT national phase application, the three years run from the international filing date, not from the date of entry into the Korean national phase.
- If no request for examination is filed within the three years, the patent application is deemed withdrawn. This period cannot be extended.
This article is based on the Patent Act in force from 11 November 2025. Last verified on 9 October 2026.
Last verified
Deadline for the request for examination at a glance
| Type of application | Deadline for the request for examination | Basis |
|---|---|---|
| Patent application filed directly in Korea | 3 years from the Korean filing date | Patent Act, Art. 59(2) |
| PCT national phase application (international patent application) | 3 years from the international filing date | Patent Act, Arts. 59(2) and 199(1) |
| Divisional application, separational application | 3 years from the filing date of the original application. If the 3 years have passed, 30 days from the date the divisional or separational application is filed | Patent Act, Arts. 52(2), 52-2(2) and 59(3) |
| Converted application | 3 years from the filing date of the utility model application. If the 3 years have passed, 30 days from the date the converted application is filed | Patent Act, Arts. 53(2) and 59(3) |
| Application filed by the legitimate right holder | If the 3 years have passed, 30 days from the date the legitimate right holder files the application | Patent Act, Art. 59(3) |
| Applications filed on or before 28 February 2017 | 5 years from the filing date (previous provision) | Addenda to Act No. 14035, Art. 19 |
The deadline is three years from the filing date
Any person may file a request for examination with the Minister of Intellectual Property (지식재산처장) within three years from the filing date of the patent application (Patent Act, Art. 59(2)). [1] A patent application is examined only when a request for examination has been filed (Art. 59(1)). [1]
The three years are counted from the Korean filing date. The filing date is the date on which the written patent application reaches the Minister of Intellectual Property (Patent Act, Art. 42-2(1)). [1]
For an application with a priority claim under the Treaty, the reference date is also the Korean filing date, not the priority date. Article 54(1) of the Patent Act treats the foreign filing date as the Korean filing date only for the application of Articles 29 and 36. [1] Article 59 is not among them.
Laying-open of the application is different. The period of one year and six months for laying-open is counted from the filing date of the application on which the priority claim is based (Patent Act, Art. 64(1), subparagraph 1). [1]
The first day of a period is not counted (Patent Act, Art. 14, subparagraph 1). [1] For an application filed on 13 March 2026, the deadline is 13 March 2029. If the last day of a period is a Saturday or an official holiday, the period expires on the next day (Art. 14, subparagraph 4). [1]
The period for the request for examination cannot be extended. The period that Article 15(1) of the Patent Act allows to be extended is the period for filing a petition for trial under Article 132-17. [1] That is the trial against a decision of rejection (decision to reject a patent application) and similar decisions. The Patent Examination Guidelines (특허·실용신안 심사기준) classify the period for the request for examination as a statutory period, and state that among statutory periods only that period for filing a petition for trial can be extended. [3]
Applications filed on or before 28 February 2017 had five years
The period for the request for examination was reduced from five years to three years on 1 March 2017. Act No. 14035, promulgated on 29 February 2016, amended Article 59(2). The Act entered into force one year after its promulgation. [1][2]
Article 19 of the Addenda to Act No. 14035 provides that the previous provision applies to patent applications filed before the Act entered into force. [1] The Examination Guidelines state the period as five years for patent applications filed on or before 28 February 2017. [3]
The last filing date to which the five-year rule applies is 28 February 2017. For an application filed on that date, the five years ended on 28 February 2022.
An amended Patent Act (Act No. 21955) was promulgated on 15 September 2026 and enters into force on 16 March 2027. This amendment does not change Article 59. [9]
For a PCT national phase application, the three years run from the international filing date
An international application designating Korea is deemed a patent application filed on its international filing date (Patent Act, Art. 199(1)). [1] The deadline for the request for examination of an international patent application is therefore three years from the international filing date.
The Supreme Court of Korea reached the same conclusion in Supreme Court Decision 95Nu3336 Decided June 16, 1995. The Court held that the period starts on the international filing date, not on the date the translation was submitted to the Korean patent office. [10] At that time, the period for the request for examination was five years. The Examination Guidelines also cite this judgment and state three years from the international filing date. [3]
The applicant of an international patent application can request examination only after submitting the Korean translation and paying the official fees (Patent Act, Art. 210, subparagraph 1). [1] An international patent application filed in Korean has no translation requirement. [1]
For an international patent application filed in a foreign language, the period for submitting the translation is two years and seven months from the priority date (Patent Act, Art. 201(1)). [1] The Patent Act calls this period the period for submitting domestic documents (국내서면제출기간).
The period for submitting the translation can be postponed by one month. The applicant states the request for extension in the document under Article 203(1). That document is filed from one month before the expiration date of the period for submitting domestic documents until that expiration date (proviso to Art. 201(1)). [1] In this case, the translation can be submitted until the date one month after that expiration date. [1]
The period for submitting the translation and the deadline for the request for examination have different reference dates. The translation period is counted from the priority date. The request for examination is counted from the international filing date.
The applicant can replace the Korean translation with a new one within the period for submitting domestic documents. However, this is not possible after the applicant has filed a request for examination (Patent Act, Art. 201(3)). [1]
A divisional application has a further 30 days from the date it is filed
A divisional application is deemed filed at the time the original application (parent application) was filed (Patent Act, Art. 52(2)). [1] The three years for a divisional application are therefore also counted from the filing date of the original application.
For a divisional application filed after three years from the filing date of the original application, examination can be requested within 30 days from the date the divisional application is filed (Patent Act, Art. 59(3)). [1] The same applies to a separational application (splitting-off), a converted application and an application filed by the legitimate right holder. [1] A converted application is deemed a patent application filed at the time the utility model application was filed (Patent Act, Art. 53(2)). [1]
If no request for examination is filed within the 30 days, the divisional application is also deemed withdrawn (Patent Act, Art. 59(5)). [1]
If the deadline is missed, the application is deemed withdrawn
If no request for examination is filed within the period in which it can be filed, the patent application is deemed withdrawn (Patent Act, Art. 59(5)). [1]
Relief is limited to cases with good cause. The applicant can file the request for examination within two months from the date on which the cause ceased to exist (Patent Act, Art. 67-3(1)). [1] However, this is not possible once one year has passed from the expiration date of the period for the request for examination. [1] Both the three-year period and the 30-day period for divisional and similar applications are covered by this relief. [1]
When this request for examination is filed, the patent application is deemed not to have been withdrawn (Art. 67-3(2)). [1]
A request for examination cannot be withdrawn, and it requires claims
A request for examination cannot be withdrawn (Patent Act, Art. 59(4)). [1] The Examination Guidelines state that a request for examination is accepted only once for one application. [3]
The applicant cannot request examination if the specification does not contain claims (Patent Act, Art. 59(2), subparagraph 1). [1] The applicant of a patent application in a foreign language also cannot request examination if the Korean translation has not been submitted (Art. 59(2), subparagraph 2). [1]
The request for examination is made with the written request for examination in Form 22 of the Enforcement Rules of the Patent Act (특허법 시행규칙). When examination is requested at the same time as the patent application is filed, a statement to that effect in the written patent application is sufficient. This is limited to the case where a specification containing claims is attached (Enforcement Rules, Art. 37(1)). [4]
The fee for request for examination is KRW 166,000 plus KRW 51,000 for each claim (Regulation on the Collection of Patent Fees, etc. (특허료 등의 징수규칙), Art. 2(1), subparagraph 7). [5] This amount applies to applications filed on or after 1 August 2023. Applications filed before that date follow the previous provision (Addenda to Ordinance of the Ministry of Trade, Industry and Energy No. 517, Art. 3(2)). [5] The previous amount is KRW 143,000 plus KRW 44,000 for each claim. [5]
The fee for request for examination is due by the day after the receipt number is issued (Fee Regulation, Art. 8(4)). [5] The case is different when deferred examination is requested at the same time as the request for examination. The fee can then be paid up to two months before the time at which the applicant wishes examination to take place (Art. 8(4)). [5]
A third party can also request examination
A person other than the applicant can also file a request for examination. This is because the subject of Article 59(2) is “any person”. [1] When a person other than the applicant files a request for examination, the Minister of Intellectual Property notifies the applicant of that fact (Patent Act, Art. 60(3)). [1]
A request for examination by a third party can bring other deadlines of the applicant forward. An applicant who filed the application without claims must add the claims by the date three months after receiving that notification. If the date one year and two months after the reference date for laying-open of the application is earlier, that earlier date applies (Patent Act, Art. 42-2(2)). [1] The deadline for submitting the Korean translation of a patent application in a foreign language is set in the same way (Patent Act, Art. 42-3(2)). [1]
For an international patent application, a person other than the applicant can request examination only after the period for submitting domestic documents has passed (Patent Act, Art. 210, subparagraph 2). [1] If the period for submitting the translation has been extended, this means after the extended period has passed. [1]
If the number of claims increases through an amendment of the specification after a third party has requested examination, the applicant pays the fee for request for examination for the added claims (Patent Act, Art. 82(2)). [1]
After the request, the time of examination can be postponed
An applicant who has filed a request for examination can request deferred examination. This is used when the applicant wishes examination to take place later than 24 months after the date of the request for examination (Enforcement Rules of the Patent Act, Art. 40-3(1)). [4]
The request for deferred examination is filed within nine months from the date of the request for examination. [4] The time at which the applicant wishes examination to take place must be within five years from the filing date. [4] When deferred examination is requested at the same time as the request for examination, it is sufficient to state this and the desired time in the written request for examination. [4]
When such a request is filed, the examiner may defer examination until that time (Art. 40-3(3)). [4] Examination is not deferred in the following cases. [4]
- The application is a separational application, a converted application or an application filed by the legitimate right holder.
- A decision to grant accelerated examination (expedited examination) has been made for the patent application.
- A notice of grounds for rejection or a decision to grant was already issued before the request for deferred examination.
Example
The dates are assumed. The last day of each period is assumed not to be a Saturday or an official holiday.
| Case | Reference date | Deadline for the request for examination |
|---|---|---|
| Application filed in Korea on 13 March 2026, claiming priority from a US application filed on 14 March 2025 | Korean filing date, 13 March 2026 | 13 March 2029 |
| PCT application with a priority date of 10 November 2023 and an international filing date of 8 November 2024 | International filing date, 8 November 2024 | 8 November 2027 |
| Divisional application filed on 1 September 2026 from an original application filed on 15 June 2022 | Divisional filing date, 1 September 2026 | 1 October 2026 |
In the second case, the period for submitting domestic documents ends on 10 June 2026, which is two years and seven months from the priority date. If entry into the Korean national phase is made on that day, about 17 months remain until the deadline for the request for examination.
How Korea differs
The Korean deadline is three years, the same as in Japan. The reference date differs from that in China.
| Country | Deadline for the request for examination | If the deadline is missed | Basis |
|---|---|---|---|
| Korea | 3 years from the filing date | Deemed withdrawn | Patent Act, Art. 59 [1] |
| Japan | 3 years from the filing date | Deemed withdrawn | Japanese Patent Act (特許法), Art. 48-3(1) and (4) [6] |
| Europe (EPO) | 6 months from the date on which the European Patent Bulletin mentions the publication of the European search report | Deemed withdrawn | Rule 70(1) EPC, Article 94(2) EPC [7] |
| China | 3 years from the filing date. If priority is claimed, 3 years from the priority date | Deemed withdrawn unless there is a justifiable reason | Chinese Patent Law (专利法), Art. 35; Implementing Regulations (实施细则), Art. 12 [8] |
China reads the “filing date” of an application with a priority claim as the priority date (Implementing Regulations of the Chinese Patent Law, Art. 12). [8] A Korean application and a Chinese application that claim the same priority therefore have different deadlines for the request for examination. The Korean deadline is later by the difference between the priority date and the Korean filing date.
In Japan, a request for examination also cannot be withdrawn (Japanese Patent Act, Art. 48-3(3)). [6] The same applies in Europe (Rule 70(1) EPC). [7] In Europe, the request for examination is not deemed filed until the examination fee has been paid (Article 94(1) EPC). [7]
What applicants should do
- In general, we suggest tracking the deadline for the request for examination of a Korean case separately, by the Korean filing date or the international filing date, not by the priority date.
- If Chinese and Korean applications are managed in one table, we suggest keeping the reference date column separate for each country.
- We suggest finalizing the claims before the request for examination. A request for examination cannot be withdrawn, and the fee for request for examination is set by the number of claims.
- In the PCT national phase, we suggest checking whether the translation may need to be submitted again before filing the request for examination.
- For a divisional application filed after three years from the filing date of the original application, we suggest filing the request for examination at the same time as the divisional application. The 30-day period is easy to miss.
- If the purpose is to delay examination, we suggest comparing two options together: postponing the request until shortly before the deadline, and deferred examination.
- Please confirm the deadline in an individual case with your Korean agent.
FAQ
Is the deadline for the request for examination counted from the priority date?
No. Article 59(2) of the Patent Act sets the period as three years from the filing date. [1] For a PCT application, it is three years from the international filing date. [1][3]
Can the period for the request for examination be extended?
No. The only period that Article 15(1) of the Patent Act allows to be extended is the period for filing a petition for trial under Article 132-17. [1][3]
Can an application be restored after the deadline is missed?
Only when there is good cause. The request must be filed within two months from the date on which the cause ceased to exist and within one year from the expiration date of the period (Patent Act, Art. 67-3). [1]
Can examination be requested at the same time as filing?
Yes. When a specification containing claims is attached, a statement in the written patent application that examination is requested is sufficient (proviso to Enforcement Rules of the Patent Act, Art. 37(1)). [4]
Some guides say five years from the filing date. Is that wrong?
That is the previous provision, which applied to applications filed on or before 28 February 2017. [1][2] Applications filed on or after 1 March 2017 have three years. [1]
How DEFINE IP Law Firm handles this
DEFINE IP Law Firm manages the number of claims as a cost item during prosecution. We confirm with the applicant which claims to keep at two points: before the examination request and before payment of the registration fee. We check the deadline for the request for examination separately, based on the Korean filing date or the international filing date. For questions about the timing of the request for examination of Korean applications, please write to contact@defineip.kr.
Sources
- Patent Act (특허법), Act No. 21134, in force from 11 November 2025. Articles 14, 15, 42-2, 42-3, 52, 52-2, 53, 54, 59, 60, 64, 67-3, 82, 132-17, 199, 201, 203 and 210; Addenda (Act No. 14035, promulgated 29 February 2016), Articles 1 and 19. https://www.law.go.kr/법령/특허법 (verified 9 October 2026)
- Patent Act (특허법), Act No. 13096, in force from 29 July 2015 (text before the amendment). Article 59(2). Version history at https://www.law.go.kr/법령/특허법 (verified 9 October 2026)
- Ministry of Intellectual Property (지식재산처), Patent Examination Guidelines (특허·실용신안 심사기준), MOIP Established Rule (지식재산처예규) No. 7, issued 12 March 2026, in force from 13 March 2026. Part 1, Chapter 3; Part 5, Chapter 1, Section 5. https://www.law.go.kr/행정규칙/특허·실용신안심사기준 (verified 9 October 2026)
- Enforcement Rules of the Patent Act (특허법 시행규칙), Prime Ministerial Decree No. 2115, in force from 14 May 2026. Articles 37 and 40-3. https://www.law.go.kr/법령/특허법시행규칙 (verified 9 October 2026)
- Regulation on the Collection of Patent Fees, etc. (특허료 등의 징수규칙), Prime Ministerial Decree No. 2098, in force from 27 February 2026. Article 2(1), subparagraph 7, Article 8(4), Addenda (Ordinance of the Ministry of Trade, Industry and Energy (산업통상자원부령) No. 517, 1 August 2023), Article 3(2). The previous amount is from the version in force from 4 February 2023 (Ordinance of the Ministry of Trade, Industry and Energy No. 499), Article 2(1), subparagraph 7. https://www.law.go.kr/법령/특허료등의징수규칙 (verified 9 October 2026)
- Japan, Patent Act (特許法, Act No. 121 of 1959), Article 48-3 (第48条の3), e-Gov 法令検索. https://laws.e-gov.go.jp/law/334AC0000000121 (verified 9 October 2026)
- EPO, Rule 70 EPC (marked as amended with effect from 1 April 2025) and Article 94 EPC. https://www.epo.org/en/legal/epc/2020/r70.html , https://www.epo.org/en/legal/epc/2020/a94.html (verified 9 October 2026)
- China National Intellectual Property Administration (国家知识产权局), Patent Law (专利法, 2020年修正), Article 35, and Implementing Regulations of the Patent Law (专利法实施细则, 2023年修订), Article 12. https://www.cnipa.gov.cn/art/2020/11/23/art_97_155167.html , https://www.cnipa.gov.cn/art/2023/12/21/art_98_189197.html (verified 9 October 2026)
- Patent Act (특허법), Act No. 21955, promulgated 15 September 2026, to enter into force on 16 March 2027. Article 59. https://www.law.go.kr/법령/특허법 (verified 9 October 2026)
- Supreme Court of Korea (대법원), Supreme Court Decision 95Nu3336 Decided June 16, 1995 (대법원 1995. 6. 16. 선고 95누3336 판결, revocation of a disposition returning a request for examination of a patent application). https://www.law.go.kr/판례/(95누3336) (verified 9 October 2026)