How much do extensions of time cost at the Korean patent office?

Sangwook Je, Partner · Published 27 October 2026

Last verified 8 October 2026

Extension fees at a glance

As of October 2026. The amounts are those for patent application procedures.

The Fee Regulation also sets statutory period extension fees of KRW 60,000 for a third extension, KRW 120,000 for a fourth and KRW 240,000 for a fifth or later extension. [1]

The month-by-month amounts for designated periods were introduced by the Fee Regulation in force from 1 January 2013. The amounts have not changed since then. [1]

Two kinds of period can be extended

In Korean patent procedure, a period that can be extended is either a designated period (지정기간) or a statutory period (법정기간). A designated period is a period set in a notice by the examiner or by the Minister of Intellectual Property. A statutory period is a period set directly by the Patent Act (특허법).

A designated period can be shortened or extended on request (Patent Act, Art. 15(2)). [2] The period for submission of a written argument in response to a notice of grounds for rejection is the typical designated period. It is set within four months (Enforcement Rules of the Patent Act (특허법 시행규칙), Art. 16(1), subparagraph 2). [3] Before the amendment of 11 July 2025, the range was within two months. [3]

The only statutory period that can be extended on request under Article 15 of the Patent Act is the period for filing a petition for trial in an appeal against the decision to reject. Article 15(1) names only the period for filing a petition for trial under Article 132-17 as extendable. [2] The Patent Examination Guidelines (특허·실용신안 심사기준) also state that, among statutory periods, only this period for filing a petition for trial can be extended. [5]

Both kinds of extension are requested with the request for extension of the period in Form 10 of the Enforcement Rules of the Patent Act (Enforcement Rules, Art. 16(2)). [3]

The fee for a designated period rises with each month

The extension fee for a designated period divides the extension into one-month parts and charges a different amount for each month. The first month costs KRW 20,000 and the fourth month costs KRW 120,000. [1]

Each request for extension is treated as a request for one month, and several months can be requested at once. If the extension requested is shorter than one month, it is treated as one month (Regulations for the Handling of Patent and Utility Model Examination Affairs (특허·실용신안 심사사무취급규정), Art. 23(2)). [4] An extension of only a few days therefore costs the fee for one month.

For an extension of several months, the total is the sum of the amounts for each part. The Fee Regulation sets the amount for each part of the extension period, not for each request (Art. 2(1), subparagraph 13-2). [1] A two-month extension costs KRW 50,000, a three-month extension KRW 110,000 and a four-month extension KRW 230,000.

Designated periods in trial proceedings have their own table with the same amounts (Fee Regulation, Art. 2(3), subparagraph 11-2). [1]

The period for submission of a written argument is extended on receipt of the request, up to four months

For the period for submission of a written argument, a request for extension of up to four months is deemed approved when it is received. The four months are counted from the expiration date of the period originally designated (Handling Regulations, Art. 23(3)). [4]

The part beyond four months is approved only if the examiner finds it necessary (Art. 23(4)). [4] The Examination Guidelines list seven grounds for approval. One is the appointment or change of an agent within one month before the expiration of the period. Another is a foreign examination result received within two months before the expiration, filed together with the request for extension of the period. A further ground is that a test related to the grounds for rejection needs more time. [5]

There is an exception for applications in which a third party requested examination. The Examination Guidelines state that, in this case, an extension is not approved on the first five of the seven grounds. [5]

Beyond four months, the fee also rises to KRW 240,000 for each month. [1] A five-month extension costs KRW 470,000 in total.

The extension is counted from the day after the original period ends. If the last day of the original period is a public holiday, the extension is still counted from the day after that holiday. [5]

For a designated period in substantive examination other than the period for submission of a written argument, the request for extension of the period is deemed approved when it is received (Handling Regulations, Art. 23(3)). [4]

The period for amendment under an order to amend the procedure (Patent Act, Art. 46) is treated separately. The Examination Guidelines state that this period can be extended up to four months in total. They also state that a further extension is possible if there is a cause not attributable to the person who filed the request. [5]

The period for filing a petition for trial can be extended once, by up to 30 days

An appeal against the decision to reject is filed within three months from the date on which the certified copy of the decision of rejection is served (Patent Act, Art. 132-17). [2] This period can be extended on request only once, by up to 30 days (Patent Act, Art. 15(1)). [2]

A person in a remote area or an area with poor access to transport can obtain one more extension, by up to 30 days (Enforcement Rules, Art. 16(4)). [3]

The extension fee for a statutory period is KRW 20,000 for the first extension and KRW 30,000 for the second. [1] The extensions provided in Article 15(1) of the Patent Act and Article 16(4) of the Enforcement Rules are two in total, including the additional extension. [2][3] Article 2(3), subparagraph 11 of the Fee Regulation, which sets the fees related to trial requests, sets the same amounts. [1]

When the period for filing a petition for trial is extended, the period for requesting re-examination is extended with it. Article 67-2(1) of the Patent Act ties the period for requesting re-examination to the extended period for filing a petition for trial. [2] The same applies to the period for filing a divisional application after a decision of rejection (Patent Act, Art. 52(1), subparagraph 2). [2]

The fee is due by the day after the request and is refunded if the extension is not approved

The extension fee is due by the day after the receipt number is issued (Fee Regulation, Art. 8(1)). [1] If that day is a public holiday, the fee is due by the first working day after it (Art. 8(2)). [1]

If the fee is not paid, the applicant receives a request for amendment with a time limit. If the fee is still not paid within that time limit, the request for extension is invalidated. [5]

A request for extension must be filed before the period ends. A request for extension of the period filed after the designated period has passed is returned after an opportunity to explain has been given, and the fee paid is refunded. [5] The fee is also refunded when the request for extension is not approved. [5]

A request to shorten a designated period carries no fee. The Fee Regulation has no fee item for shortening a designated period. [1] The instructions for the form (Form 10) also provide that the fee field is deleted in a request for shortening. [3]

Extension fees are not subject to fee reductions. Article 7(1) of the Fee Regulation sets the fees subject to exemption, reduction and temporary reduction in attached Table 4, attached Table 5 and attached Table 6. [1] The fees for which attached Table 5 sets a reduction rate are the application fee, the fee for request for examination, annual fees and the trial request fee for a trial to confirm the scope of a right. Extension fees do not appear in any of the three attached Tables or in attached Table 7, the special provision for disasters. [1]

The fee for extending the period for filing the Korean translation is KRW 20,000

For an international patent application filed in a foreign language, the period for filing the Korean translation can be extended by one month. The period for submitting domestic documents is 31 months from the priority date (Patent Act, Art. 201(1)). [2]

To obtain the extension, the applicant states this intention in the document under Article 203(1) of the Patent Act. The document is filed between one month before the expiration date of the period for submitting domestic documents and that expiration date. [2] In this case, the Korean translation can be filed until the day one month after the expiration date. [2] If the Korean translation was already filed before that document, the period is not extended (proviso to Art. 201(1) of the Patent Act). [2]

The fee for this extension is KRW 20,000 per case (Fee Regulation, Art. 2(1), subparagraph 11-2). [1]

Late payment of the registration fee is not a request for extension

The annual fees for the first three years are paid within three months from receipt of a certified copy of the decision to grant (Fee Regulation, Art. 8(5)). [1] After this period, payment is still possible within six months. No request for extension is needed, and an additional fee of 3% to 18% of the annual fees is paid depending on the number of months elapsed (Art. 8(6)). [1]

Example: extending the period for submission of a written argument

The figures assume a period for submission of a written argument designated as four months that is then extended. The fee is set by the extension period, so it is the same whatever the length of the period originally designated. [1] Agent fees are not included.

After a decision of rejection, extending the period for filing a petition for trial by 30 days costs KRW 20,000. [1]

How Korea differs

In both Korea and the United States, the total fee grows as the extension gets longer. The way the amounts are stated, the time of the request and the limit on extensions are different.

The US amounts are those of the USPTO Fee Schedule effective 19 January 2025 (marked as last revised 14 August 2026). [6] They are the same as the amounts in 37 CFR 1.17(a) as of 6 October 2026. [8]

The amounts in the US fee schedule are totals for an extension up to that month. If one more month is needed after the one-month fee has been paid, the applicant pays the two-month amount less the amount already paid (MPEP 710.02(e)). [7]

A US extension runs up to five months after the time period set for reply and cannot go beyond the maximum statutory period (37 CFR 1.136(a)(1)). [8] In Korea, the period for submission of a written argument is extended on receipt of the request up to four months, and any further extension needs the approval of the examiner. [4]

The US rule determines the extension period and the amount by the date on which the petition and the fee are filed (37 CFR 1.136(a)(2)). [8] In Korea, a request for extension of the period filed after the designated period has passed is returned. [5]

The United States applies a 60% reduction for small entities and an 80% reduction for micro entities. [7] Korean extension fees have no reduction based on the size of the applicant. [1]

What applicants should do

• In general, we suggest deciding how many months are needed and requesting the extension of the period for submission of a written argument in one request. This is because the range that is approved on receipt is fixed at four months.
• The fourth month costs KRW 120,000, six times the first month. We suggest first reviewing whether a response is possible within three months.
• If an extension beyond four months is needed, it is better to have the reason for the extension ready in advance. To rely on a foreign examination result, that result must be filed together with the request for extension of the period.
• The request for extension must be received before the period ends. We suggest leaving a few days rather than filing on the expiration date.
• After a decision of rejection, the schedule should take into account that the period for filing a petition for trial can be extended only once.
• For an individual case, please confirm the time limit and the amount with your agent on the basis of the notice.

FAQ

How much does a one-month extension to respond to a Notice of Preliminary Rejection cost in Korea?

KRW 20,000. This is the designated period extension fee for the part up to one month. [1]

Can an extension be requested in several separate requests?

Yes. Requests for extension are for one month each, and one request or two or more requests can be filed at once. [4] However, the request must be filed before the designated period ends. [5]

What happens to the fee if a request for extension is not approved?

It is refunded. The Examination Guidelines state that the fee paid is refunded also when a request for extension is not approved. [5]

Do small and medium-sized enterprises or individuals receive a reduction of the extension fee?

No. Extension fees are not among the fees subject to reduction in attached Tables 4 to 7 of the Fee Regulation. [1]

Can the period for requesting examination also be extended by paying a fee?

No. The only statutory period that can be extended under Article 15 of the Patent Act is the period for filing a petition for trial in an appeal against the decision to reject. [2][5]

How DEFINE IP Law Firm handles this

When a notice is received, DEFINE IP Law Firm checks the response deadline together with the last day to which it can be extended. We decide with the applicant whether an extension is needed before the deadline ends. For questions about time limits and extensions for Korean applications, please write to contact@defineip.kr.

Sources

1. 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. Art. 2(1), subparagraphs 11-2, 13 and 13-2, Art. 2(3), subparagraphs 11 and 11-2, Art. 7, Art. 8, attached Tables 4 to 7. The designated period extension fee was introduced by Ordinance of the Ministry of Knowledge Economy (지식경제부령) No. 280, in force from 1 January 2013. https://www.law.go.kr/법령/특허료등의징수규칙 (verified 8 October 2026)
2. Patent Act (특허법), Act No. 21134, in force from 11 November 2025. Articles 15, 52, 67-2, 132-17, 201 and 203. https://www.law.go.kr/법령/특허법 (verified 8 October 2026)
3. Enforcement Rules of the Patent Act (특허법 시행규칙), Prime Ministerial Decree No. 2115, in force from 14 May 2026. Article 16, Form 10. The previous range in Art. 16(1) is that of the version in force from 1 November 2024. https://www.law.go.kr/법령/특허법시행규칙 (verified 8 October 2026)
4. Ministry of Intellectual Property (지식재산처), Regulations for the Handling of Patent and Utility Model Examination Affairs (특허·실용신안 심사사무취급규정), MOIP Directive (지식재산처훈령) No. 41, in force from 1 July 2026. Article 23. https://www.law.go.kr/행정규칙/특허·실용신안심사사무취급규정 (verified 8 October 2026)
5. Ministry of Intellectual Property (지식재산처), Patent Examination Guidelines (특허·실용신안 심사기준), MOIP Established Rule (지식재산처예규) No. 7, in force from 13 March 2026. Part 1, Chapter 3, sections 3.(5) and 4. https://www.law.go.kr/행정규칙/특허·실용신안심사기준 (verified 8 October 2026)
6. USPTO, USPTO Fee Schedule, effective 19 January 2025 (marked as last revised 14 August 2026). 37 CFR 1.17(a)(1) to (5). https://www.uspto.gov/learning-and-resources/fees-and-payment/uspto-fee-schedule (verified 8 October 2026)
7. USPTO, Manual of Patent Examining Procedure 710.02(e) Extension of Time [R-01.2024]. https://www.uspto.gov/web/offices/pac/mpep/s710.html (verified 8 October 2026)
8. US Code of Federal Regulations, 37 CFR 1.17(a) and 1.136(a), eCFR version as of 6 October 2026. https://www.ecfr.gov/current/title-37/chapter-I/subchapter-A/part-1 (verified 8 October 2026)