Brief summary
- In Korea, a divisional application (분할출원) cannot be filed merely because the original application (parent application) is pending. It can be filed only within the three periods set by Article 52(1) of the Patent Act (특허법).
- The three periods are the period in which an amendment can be made, 3 months after a decision of rejection (decision to reject a patent application), and 3 months after a decision to grant. The 3 months run from the date on which the certified copy of the decision is served.
- The 3 months after a decision to grant end at registration of the grant of a patent (registration of establishment of a patent right). Once the annual fees (the registration fee) are paid and the grant of the patent is registered, a divisional application cannot be filed, even if part of the 3 months remains.
The time limits are those of the Patent Act in force from 11 November 2025. Last verified on 8 October 2026.
Last verified
Periods for filing a divisional application at a glance
| Stage of the original application | Period in which a divisional application can be filed | Basis |
|---|---|---|
| Before a notice of grounds for rejection is received | At any time until the certified copy of the decision to grant is served | Patent Act, Art. 52(1), subparagraph 1, and Art. 47(1), main clause |
| After a notice of grounds for rejection is received | The period for submission of a written argument for that notice | Art. 52(1), subparagraph 1, and Art. 47(1), subparagraphs 1 and 2 |
| When re-examination is requested | Together with the request for re-examination | Art. 52(1), subparagraph 1, and Art. 47(1), subparagraph 3 |
| After a decision of rejection is received | 3 months from service of the certified copy of the decision of rejection. If the period for filing a petition for trial is extended, the extended period | Art. 52(1), subparagraph 2 |
| After a decision to grant is received | 3 months from service of the certified copy of the decision to grant. If the date when the applicant intends to have the grant of the patent registered is earlier, until that date | Art. 52(1), subparagraph 3 |
| After a trial decision made to register a patent is received | 3 months from service of the certified copy of the trial decision. If the date when the applicant intends to have the grant of the patent registered is earlier, until that date | Art. 52(1), subparagraph 3 |
| After an appeal against the examiner’s decision to reject a patent application is dismissed | No divisional application. Only a separational application, within 30 days from service of the certified copy of the trial decision | Art. 52-2(1) |
A divisional application can be filed only in three periods
Article 52(1) of the Patent Act limits the time for filing a divisional application to three periods. [1] The first is the period in which the specification or drawings can be amended under Article 47(1) of the Patent Act. The second is 3 months from service of the certified copy of a decision of rejection. The third is 3 months from service of the certified copy of a decision to grant. [1]
A divisional application filed outside the three periods is not accepted. The Patent Examination Guidelines (특허·실용신안 심사기준) state that a divisional application filed after the statutory period is returned after the applicant has been given an opportunity to explain. [4]
The scope of a divisional application is the matter described in the specification or drawings originally attached to the written patent application of the original application (Patent Act, Art. 52(1)). [1] An invention deleted from the original application by amendment can still be the subject of a divisional application if it was in the original specification. [4]
If the original application is a patent application in a foreign language, the Korean translation must be filed first. The proviso to Article 52(1) of the Patent Act allows division only when the Korean translation has been submitted. [1]
After a notice of grounds for rejection, a divisional application can be filed only in the period for submission of a written argument
Before a notice of grounds for rejection is received, a divisional application can be filed at any time until the certified copy of the decision to grant is served. This is because the main clause of Article 47(1) of the Patent Act allows amendment until then. [1]
After a notice of grounds for rejection is received, amendment is possible only in the period for submission of a written argument for that notice (Patent Act, Art. 47(1), subparagraphs 1 and 2). [1] A divisional application can be filed only in the same period. The examiner sets the period for submission of a written argument within a maximum of 4 months (Enforcement Rules of the Patent Act (특허법 시행규칙), Art. 16(1), subparagraph 2). [2] A period set by the examiner can be extended on request (Patent Act, Art. 15(2)). [1]
Therefore, a divisional application cannot be filed from the end of the period for submission of a written argument until the certified copy of the next notice or decision is received. The Examination Guidelines also limit a divisional application after a notice of grounds for rejection to two cases. One is filing within the period for submission of a written argument. The other is filing together with a request for re-examination. [4]
When re-examination is requested, a divisional application can be filed together with the request (Patent Act, Art. 47(1), subparagraph 3). [1] When re-examination is requested, the earlier decision to grant or decision of rejection is deemed revoked (Patent Act, Art. 67-2(3)). [1] For this reason, after a request for re-examination, a divisional application can no longer be filed in the 3 months counted from the certified copy of the earlier decision. [4]
After a decision of rejection, the period is 3 months
A divisional application can be filed within 3 months from service of the certified copy of a decision of rejection (Patent Act, Art. 52(1), subparagraph 2). [1] These 3 months are the same as the period in which an appeal against the examiner’s decision to reject a patent application (trial on rulings rejecting patent applications) can be filed (Patent Act, Art. 132-17). [1]
If the period for filing a petition for trial is extended, the period for a divisional application is extended by the same length. The Minister of Intellectual Property can extend the period for filing a petition for trial once, by up to 30 days, on request or ex officio (Patent Act, Art. 15(1)). [1] A person in a remote area or an area with poor access to transport can receive one further extension of up to 30 days (Enforcement Rules of the Patent Act, Art. 16(4)). [2]
A divisional application can still be filed after an appeal against the decision to reject has been filed, if it is within the 3 months. The Examination Guidelines state this expressly. [4] After the 3 months, a divisional application cannot be filed even if the appeal is pending. The Examination Guidelines state that a divisional application is possible only within the period for filing a petition for trial. [4]
This period used to be 30 days. [1] The 3 months apply to applications for which the certified copy of the decision of rejection was served on or after 20 April 2022 (Addenda to Act No. 18505, Art. 3(1)). [1]
After a decision to grant, the period is 3 months and ends at registration
A divisional application can be filed within 3 months from service of the certified copy of a decision to grant (Patent Act, Art. 52(1), subparagraph 3). [1] However, if the date when the applicant intends to have the grant of the patent registered is earlier than the end of the 3 months, the period ends on that date (proviso to the same subparagraph). [1]
The Minister of Intellectual Property registers the grant of the patent when the applicant has paid the annual fees (Patent Act, Art. 87(2), subparagraph 1). [1] Therefore, paying the registration fee immediately after the decision to grant shortens the period for a divisional application by that much. The Examination Guidelines also describe this period as “before registration”. [4]
The same 3 months apply when the applicant receives a trial decision made to register a patent in an appeal against the decision to reject. [1]
The divisional application after a decision to grant was introduced on 29 July 2015. It applies to applications for which the certified copy of the decision to grant was served on or after that date (Addenda to Act No. 13096, Art. 2(2)). [1]
After the appeal is dismissed, only a separational application remains
If an appeal against the decision to reject is dismissed, a divisional application cannot be filed. In this case a separational application (splitting-off; 분리출원) can be filed within 30 days from service of the certified copy of the trial decision (Patent Act, Art. 52-2(1)). [1]
The claims of a separational application are restricted. They can contain only claims that were not rejected in the decision of rejection, narrowed versions of those claims, and similar claims (Patent Act, Art. 52-2(1), subparagraphs). [1]
A separational application cannot be the basis for a new divisional application (Patent Act, Art. 52-2(4)). [1] The separational application applies to applications for which an appeal against the decision to reject was filed on or after 20 April 2022 (Addenda to Act No. 18505, Art. 4). [1]
The original application must be pending, and a divisional application can be divided again
When a divisional application is filed, the original application must be pending before the Ministry of Intellectual Property (지식재산처, MOIP). If the original application has been invalidated, withdrawn or abandoned, or the decision of rejection has become final, a divisional application cannot be filed. [4] A divisional application filed on the day on which the procedure of the original application ends by withdrawal, abandonment or the like is treated as filed while the original application was pending. [4]
A divisional application can be the basis for a further divisional application. The Examination Guidelines give the example of a case where division is no longer possible from the original application because of timing, but is possible from the divisional application. [4] In this case the content of the last divisional application must be within the original specification or drawings of the first original application. [4]
The divisional application fee rises with the number of divisions. Article 2(1), subparagraph 3 of the Regulation on the Collection of Patent Fees, etc. (특허료 등의 징수규칙) sets the filing fee for a new application for the 1st division. The fee is 2 times that amount for the 2nd division, 3 times for the 3rd, 4 times for the 4th, and 5 times for the 5th and later divisions. [3] Divisional applications filed before 1 August 2023 are not counted (Addenda of 1 August 2023 to the same Regulation, Art. 3(1)). [3]
Some time limits are counted again from the divisional filing date
A divisional application is deemed filed at the time the original application was filed (Patent Act, Art. 52(2)). [1] For this reason, some time limits are given separately from the date on which the divisional application is filed.
| Procedure | Time limit | Basis |
|---|---|---|
| Request for examination | 30 days from the date of the divisional application, even if 3 years have passed from the filing date of the original application | Patent Act, Art. 59(3) |
| Korean translation of a divisional application filed in a foreign language | Until the day that is 30 days after the date of the divisional application | Art. 52(7) |
| Amendment to add claims to a divisional application filed without claims | Until the day that is 30 days after the date of the divisional application | Art. 52(8) |
| Priority document for a priority claim under the Treaty | 3 months from the date of the divisional application | Art. 52(6) |
| Withdrawal of a priority claim that was carried over automatically | 30 days from the date of the divisional application | Art. 52(5) |
If examination is not requested within the period, the divisional application is deemed withdrawn (Patent Act, Art. 59(5)). [1]
If the original application claims priority, the divisional application is also deemed to claim priority (Patent Act, Art. 52(4)). [1] This provision applies to divisional applications filed on or after 20 April 2022 (Addenda to Act No. 18505, Art. 3(2)). [1]
A PCT national phase application has its own rule on when it can be amended
A PCT national phase application (international patent application, 국제특허출원) can be amended only after three requirements are met. The official fees must be paid, the Korean translation must be submitted, and the reference date must have passed (Patent Act, Art. 208(1)). [1] The reference date is the expiration date of the period for submitting domestic documents or, if the applicant requests examination before that day, the date of the request (Patent Act, Art. 201(5)). [1] The period for submitting domestic documents is 31 months from the priority date (Patent Act, Art. 201(1)). [1]
The first period for a divisional application is “the period in which an amendment can be made under Article 47(1)” (Patent Act, Art. 52(1), subparagraph 1). [1] Article 208(1) of the Patent Act provides that, notwithstanding Article 47(1), no amendment can be made before the three requirements are met. [1]
Example
The dates below are assumed. The first day of a period is not counted, and a period in months is counted by the calendar (Patent Act, Art. 14). [1]
| Assumption | Last day for filing a divisional application |
|---|---|
| The certified copy of a decision of rejection is served on 8 October 2026 | 8 January 2027 |
| In the case above, the period for filing a petition for trial is extended by 30 days | The extended date, within 30 days after 8 January 2027 |
| The certified copy of a decision to grant is served on 8 October 2026 and the registration fee is not paid | 8 January 2027 |
| The certified copy of a decision to grant is served on 8 October 2026 and the grant of the patent is registered before 8 January 2027 | The date when the applicant intends to have the grant of the patent registered. This is earlier than 8 January 2027 |
If the last day of a period is a Saturday or a public holiday, the period ends on the following day (Patent Act, Art. 14, subparagraph 4). [1]
How Korea differs
In Korea, a divisional application cannot be filed outside the fixed periods even while the original application is pending.
| Country | When a divisional application can be filed | Basis |
|---|---|---|
| Korea | The amendment period, 3 months from service of the certified copy of a decision of rejection, and 3 months from service of the certified copy of a decision to grant (before registration) | Patent Act, in force from 11 November 2025 [1] |
| Europe (EPO) | While the earlier application is pending | Rule 36(1) EPC, in force from 1 April 2014 [5] |
| United States | The application must be copending with the earlier application. A continuing application can be filed at any time before the patenting, abandonment or termination of proceedings of the earlier application | 37 CFR 1.78(d), MPEP §201.06 [R-07.2022], §201.07 [R-08.2017] [7] |
| Japan | When an amendment can be made, 30 days from service of the certified copy of a decision to grant, and 3 months from service of the certified copy of the first decision of refusal | Japanese Patent Act, Art. 44(1), as published on e-Gov on 8 October 2026 [6][8] |
The 30 days in Japan do not apply to every decision to grant. Article 44(1), item 2 of the Japanese Patent Act excludes two kinds of decision to grant. One is a decision to grant under Article 51 as it applies mutatis mutandis under Article 163(3). The other is a decision to grant for an application referred to examination under Article 160(1). [6][8]
Applicants used to European or US practice should take care in Korea after the period for submission of a written argument has ended. Even while the original application is pending, a divisional application cannot be filed until the next notice or decision arrives.
Japan and Korea have a similar structure. The period after a decision to grant is 3 months in Korea and 30 days in Japan. [1][6]
What applicants should do
- In general, we suggest reviewing whether to file a divisional application each time a written argument is filed. After the period for submission of a written argument ends, a divisional application cannot be filed until the next notice or decision.
- After a decision to grant, we suggest deciding whether to file a divisional application before paying the registration fee. Once the grant of the patent is registered, a divisional application cannot be filed, whatever time remains.
- After a decision of rejection, we suggest reviewing the appeal and a divisional application together within the same 3 months. The separational application that remains after the appeal is dismissed has restricted claims.
- If inventions remain for which protection will still be pursued, it is worth considering keeping at least one application pending. A divisional application can be the basis for a further divisional application.
- After filing a divisional application, check that examination has been requested within 30 days. Please confirm the time limits of an individual case with your Korean agent.
FAQ
Can a divisional application be filed at any time while the original application is pending?
No. It can be filed only in the three periods set by Article 52(1) of the Patent Act. [1] After a notice of grounds for rejection is received, those periods are the period for submission of a written argument, 3 months after a decision of rejection, and 3 months after a decision to grant. [1]
A decision to grant was received and the registration fee has already been paid. Can a divisional application be filed?
Not if the grant of the patent has been registered. The period after a decision to grant ends on the date when the applicant intends to have the grant of the patent registered, if that date is earlier than the end of the 3 months. [1]
An appeal against the decision to reject has been filed. Can a divisional application be filed during the appeal?
Yes, if it is within 3 months from service of the certified copy of the decision of rejection. [4] After the appeal is dismissed, only a separational application can be filed, within 30 days. [1]
Can a divisional application be divided again?
Yes. The Examination Guidelines allow a divisional application based on a divisional application. [4] However, a separational application cannot be the basis for a divisional application. [1]
Some guides say the period for a divisional application after a decision of rejection is 30 days. Is that wrong?
That was the period for applications for which the certified copy of the decision of rejection was served before 20 April 2022. [1] For applications for which it was served on or after that date, the period is 3 months. [1]
How DEFINE IP Law Firm handles this
DEFINE IP Law Firm checks the time limit for a divisional application at three points: the filing of a written argument, a decision of rejection, and a decision to grant. For an application that has received a decision to grant, we confirm with the applicant whether to file a divisional application before the registration fee is paid. Subject matter covered by claims that are removed is recorded separately as a candidate for a divisional application. For questions about the timing of divisional applications in Korea, please write to contact@defineip.kr.
Sources
- Patent Act (특허법), Act No. 21134, in force from 11 November 2025. Articles 14, 15, 47, 52, 52-2, 59, 67-2, 87, 132-17, 201 and 208; Addenda (Act No. 18505, in force from 20 April 2022) Arts. 3 and 4; Addenda (Act No. 13096, in force from 29 July 2015) Art. 2. Wording before the amendment: Act No. 18409 (in force from 18 November 2021). https://www.law.go.kr/법령/특허법 (verified 8 October 2026)
- Enforcement Rules of the Patent Act (특허법 시행규칙), Prime Ministerial Decree No. 2115, in force from 14 May 2026. Article 16. https://www.law.go.kr/법령/특허법시행규칙 (verified 8 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 3; Addenda (No. 517, in force from 1 August 2023) Art. 3(1). https://www.law.go.kr/법령/특허료등의징수규칙 (verified 8 October 2026)
- Ministry of Intellectual Property (지식재산처), Patent Examination Guidelines (특허·실용신안 심사기준), MOIP Established Rule No. 7, in force from 13 March 2026. Part 5, Chapter 3, 4.4; Part 5, Chapter 4, 4.; Part 6, Chapter 1, 3.2 and 3.3; Part 6, Chapter 5, 2. https://www.law.go.kr/행정규칙/특허·실용신안심사기준 (verified 8 October 2026)
- EPO, Rule 36 EPC (European divisional applications), paragraph 1 in force from 1 April 2014. https://www.epo.org/en/legal/epc/2020/r36.html (verified 8 October 2026)
- Ministry of Justice of Japan, Japanese Law Translation, Patent Act (Act No. 121 of 1959) Article 44, reflecting amendments up to Act No. 3 of 2019. https://www.japaneselawtranslation.go.jp/en/laws/view/4097 (verified 8 October 2026)
- USPTO, Manual of Patent Examining Procedure §201.06 [R-07.2022], §201.07 [R-08.2017]. https://www.uspto.gov/web/offices/pac/mpep/s201.html (verified 8 October 2026)
- Digital Agency of Japan, e-Gov 法令検索 (e-Gov Laws and Regulations Search), 特許法(昭和三十四年法律第百二十一号) 第四十四条 (Patent Act, Act No. 121 of 1959, Article 44), version published on 8 October 2026. https://laws.e-gov.go.jp/law/334AC0000000121 (verified 8 October 2026)