What changes in the Korean Patent Act on 16 March 2027?

Chanjoong Kim, Partner · Published 30 October 2026

Last verified 9 October 2026

What changes

The enforcement date is 16 March 2027 for every row. The cases covered are also the same for every row. They are the cases in which the period for late payment or the period for payment of under-paid patent fees expires on or after 16 March 2027 (Act No. 21955, Addenda, Art. 2). [1]

The “later expiration date” is the later of the expiration date of the period for late payment and the expiration date of the period for payment of under-paid patent fees. [1][2] Article 81-3(6) is not revised. [1][2] The “Previous” column shows the Patent Act in force on 9 October 2026 (Act No. 21134, in force from 11 November 2025). [2]

A comparison of the 298 Articles of the current Patent Act and the amended Patent Act shows that these two are the only Articles whose text differs. [1][2] As of 9 October 2026, Act No. 21955 is the only version of the Patent Act that the Ministry of Government Legislation (법제처) lists as scheduled to enter into force. [1]

Reinstatement covers cases abandoned or lapsed because the patent fee was not paid

The amended Article 81-3 is the provision on reinstatement of cases in which the patent fee was not paid within the period. [1][2] The provisions before it are not amended. The following stays the same after 16 March 2027. [1][2]

• A person who intends to obtain registration of the grant of a patent (registration of establishment of a patent right), or a patentee, can make late payment of the patent fee within 6 months after the payment period has passed (Patent Act, Art. 81(1)). These 6 months are the “period for late payment” (추가납부기간). [2]
• Where part of the patent fee was not paid, the Minister of Intellectual Property (지식재산처장) orders payment of the under-paid patent fee (Art. 81-2(1)). The 1 month from the day the order to pay the under-paid patent fee is received is the “period for payment of under-paid patent fees” (보전기간) (Art. 81-2(2)). [2]
• If the patent fee is not paid within the period for late payment, the patent application is deemed abandoned (Art. 81(3)). The patent right is deemed to have lapsed (deemed to have expired) retroactively to the day after the end of the period covered by the patent fees already paid. [2]
• Where the period for late payment has ended but the period for payment of under-paid patent fees has not, the test is whether the under-paid patent fee was not paid within the period for payment of under-paid patent fees (Art. 81(3), parenthetical). [2]

The amounts for the payment period and the period for late payment are in “What happens if a Korean patent annual fee is paid late?” and “What is the deadline to pay the registration fee in Korea?“.

The requirement changes from “good cause” to “not intentional”

The amended Article 81-3(1) removes “good cause” from the requirements for reinstatement. [1] The amended provision excludes only the case in which the patent fee or the under-paid patent fee was intentionally not paid. [1]

The previous paragraph (1) applies only where the patent fee or the under-paid patent fee was not paid due to good cause. [2] The statement of reasons for the amendment published by the Ministry of Government Legislation says that the requirement for reinstatement is relaxed from the previous good cause to the case that is not intentional. [1]

The person named in the amended paragraph (1) is “a person who intends to obtain registration of the grant of a patent, or a patentee”. [1] This is the same as the person named in the previous paragraph (1). [2] The statement of reasons for the amendment mentions “domestic individuals, small and medium enterprises, etc.”. [1] However, the amended provision contains no wording that limits the person to domestic individuals or small and medium enterprises. [1]

The amended provision does not state what “intentional” means or which documents show that the non-payment was not intentional. [1] The amended paragraph (7) provides that matters necessary for the request for reinstatement are set by Prime Ministerial Decree. [1]

The period for the request is 1 year from the later expiration date

Under the amended paragraph (1), the period for the request for reinstatement is 1 year from the later of the expiration date of the period for late payment and the expiration date of the period for payment of under-paid patent fees. [1]

The previous paragraph (1) has two periods. Payment must be made within 2 months from the date on which the good cause ceases to exist. [2] In addition, payment is not possible after 1 year from the later of the expiration date of the period for late payment and the expiration date of the period for payment of under-paid patent fees (previous paragraph (1), proviso). [2] The amended paragraph (1) removes the “2 months from the date on which the cause ceases to exist” and keeps only the 1 year. [1]

The statement of reasons for the amendment published by the Ministry of Government Legislation says that reinstatement is requested by “paying a certain amount within the period for late payment”. [1] The period in the amended provision is not within the period for late payment. It is 1 year from the later expiration date. [1] This article follows the provision.

The request for reinstatement by paying twice the patent fee within 3 months is removed

The amended Patent Act deletes Article 81-3(3). [1]

The previous paragraph (3) provides for a request for reinstatement where the patent right has lapsed. The patentee can pay twice the patent fee within 3 months from the expiration date of the period for late payment or the period for payment of under-paid patent fees, and request reinstatement. [2] The previous paragraph (3) does not state a requirement of good cause. [2] The previous paragraph (3) covers a lapsed patent right. A patent application deemed abandoned is not mentioned in the previous paragraph (3). [2]

After the amendment, paragraph (1) is the only route to reinstatement. [1] The amended paragraph (1) names both abandoned patent applications and lapsed patent rights. [1] The method in the amended paragraph (1) is to pay an amount set by Prime Ministerial Decree and request reinstatement. [1]

Article 8(10), subparagraph 1, of the current Regulation on the Collection of Patent Fees, etc. (특허료 등의 징수규칙; below, “Fee Regulation”) (Prime Ministerial Decree No. 2098) sets the amount under the previous paragraph (3) at an amount equal to twice the patent fee. [3] This provision cites Article 81-3(3), which will be deleted. [3] The amount under the amended paragraph (1) is covered in “What is not yet settled”.

The effect of reinstatement and the limit on that effect remain

The effect of reinstatement is the same after the amendment. Where the set amount is paid and reinstatement is requested, the patent application is deemed not to have been abandoned (amended Art. 81-3(2)). [1] The patent right is deemed to have continued to exist. [1]

The period of limited effect (효력제한기간) also remains. A reinstated patent application or patent right has no effect against acts of working (practice) by other persons during the period of limited effect (amended paragraph (4)). [1] Under the amended paragraph (4), the period of limited effect runs from the day on which the period for late payment or the period for payment of under-paid patent fees has passed to the day the amount set under paragraph (1) is paid. [1] The previous paragraph (4) states the end of this period as “the day the patent fee or the under-paid patent fee is paid”. [2]

The non-exclusive license of a person who worked the invention in Korea in good faith, or prepared to do so, during the period of limited effect also remains (amended paragraph (5)). [1] The amended paragraphs (4) and (5) change “paragraph (2) or (3)”, which referred to the deleted paragraph (3), to “paragraph (2)”. [1][2] Paragraph (6), under which the holder of the non-exclusive license must pay equitable remuneration, is not revised. [1][2]

Article 87(2), subparagraph 4, is changed only to match the wording. Under the amended subparagraph 4, the Minister of Intellectual Property registers the grant of the patent when the amount set under Article 81-3(1) is paid. [1]

The current reinstatement procedure is described in “Can a lapsed Korean patent be reinstated?”.

Cases that straddle the enforcement date

The reference point is the expiration date of the period for late payment or the period for payment of under-paid patent fees. Article 2 of the Addenda provides that the amended Article 81-3 and Article 87(2) apply “beginning with cases in which the period for late payment or the period for payment of under-paid patent fees expires on or after the date this Act enters into force”. [1] The filing date, the date of registration of the grant of the patent and the last day of the payment period are not the reference point of Article 2 of the Addenda. [1]

The Addenda to Act No. 21955 consist only of Article 1 (Enforcement Date) and Article 2 (Applicability). [1] They contain no transitional measure stating how to treat cases in which the period for late payment and the period for payment of under-paid patent fees expired before 16 March 2027. [1]

The Addenda contain no provision that separately addresses the following three situations. [1]

• Cases in which the expiration date is before 16 March 2027 but the 3 months of the previous paragraph (3) end after that day. The previous paragraph (3) is deleted on that day. [1]
• Cases in which the expiration date is before 16 March 2027 but the 1 year of the proviso to the previous paragraph (1) ends after that day. [1]
• Cases in which the period for late payment expires before 16 March 2027 and the period for payment of under-paid patent fees expires on or after that day. Article 2 of the Addenda joins the two periods with “or” and does not separately address the case in which the two expiration dates fall on different sides of the enforcement date. [1] Article 81(3) provides that, where the period for late payment has ended but the period for payment of under-paid patent fees has not, the case is deemed abandoned or lapsed if the under-paid patent fee is not paid within the period for payment of under-paid patent fees. [2]

This article does not state a conclusion on whether the previous provisions continue to apply in the three situations above. As of 9 October 2026, the subordinate statutes (the Enforcement Decree of the Patent Act (특허법 시행령), the Enforcement Rules of the Patent Act (특허법 시행규칙) and the Fee Regulation) have no version scheduled to enter into force, so there are also no Addenda to subordinate statutes that address these situations. [3][4]

The approach of the Addenda differs from that of an earlier amendment. Act No. 18505, which entered into force on 20 April 2022, also revised Article 81-3(1). [6] Article 9 of its Addenda applied the amended provision also to some of the cases in which the period had been missed before the Act entered into force. [6] These were the cases in which, when the Act entered into force, 2 months had not passed from the date on which the cause ceased to exist. [6] The Addenda to Act No. 21955 contain no such provision. [1]

Example: two cases whose periods for late payment expire one day apart

Two patents are assumed for which the patent fees for the fourth year onward were not paid at all. It is assumed that no order to pay the under-paid patent fee was issued.

For Patent B, “16 March 2028” is the day reached by counting 1 year from 16 March 2027 under Article 14 of the Patent Act. [1][2] The first day of a period is not counted (Art. 14, subparagraph 1). [2] In a patent-related procedure, if the last day of a period is an official holiday, the period expires on the following day (Art. 14, subparagraph 4). [2] Official holidays here include Workers’ Day (노동절) and Saturdays. [2]

The period for late payment is 6 months after the payment period has passed (Art. 81(1)). [2] The expiration dates in the table are the days reached by counting 6 months with the day after the last day of the payment period included as the first day (Art. 14, subparagraph 1, proviso, and subparagraph 3). [2] 15 March 2027 is a Monday, 16 March 2027 is a Tuesday and 16 March 2028 is a Thursday. None of the three dates is a public holiday fixed by date in Article 2, subparagraphs 1 through 9, of the Act on Public Holidays (공휴일에 관한 법률). [7] Election days under subparagraph 10 of that Article and the days designated occasionally by the Government under subparagraph 11 are not reflected in this table. [7]

What is not yet settled

As of 9 October 2026, the matters that the amended Patent Act leaves to Prime Ministerial Decree have not been promulgated. [3][4]

The newest version of the Fee Regulation is Prime Ministerial Decree No. 2098, in force from 27 February 2026. [3] The newest version of the Enforcement Rules of the Patent Act is Prime Ministerial Decree No. 2115, in force from 14 May 2026. [4] For neither of the two, the Ministry of Government Legislation lists a version scheduled to enter into force. [3][4]

Article 55-2(1) of the current Enforcement Rules of the Patent Act is the procedure for the previous Article 81-3(1). The payment form, Form 25 of the Enforcement Rules of the Decree on Registration of Patent Rights (특허권 등의 등록령 시행규칙), is submitted with the purport stated in it. [4] One copy of a document proving that the period could not be met due to good cause is also attached. [4] Paragraph (2) of the same Article is the procedure for the request for reinstatement under Article 81-3(3), which will be deleted. [4] Which form and documents are used after the amendment is not yet set. [4]

The previous wording also remains in the Enforcement Decree of the Patent Act. Article 7-2(1), subparagraph 1 (m), of the Enforcement Decree reads “where the patent fee or the under-paid patent fee is paid under Article 81-3(1) of the Act”. [4] The Enforcement Decree also has no version scheduled to enter into force. [4]

The Utility Model Act and the Design Protection Act also change on the same day

Reinstatement of utility model rights and restoration of design rights also change in the same direction on 16 March 2027. The Utility Model Act (실용신안법) (Act No. 21953) and the Design Protection Act (디자인보호법) (Act No. 21951) were promulgated together on 15 September 2026. [5]

• Article 20 of the Utility Model Act provides that Article 81-3 of the Patent Act applies mutatis mutandis to registration fees and utility model registration. [5] The only provision that the amended Utility Model Act revises is Article 21(2), subparagraph 4. Article 2 of its Addenda provides that the amended provision of Article 21(2) applies beginning with cases in which the period for late payment or the period for payment of under-paid patent fees expires on or after the date the Act enters into force. [5]
• The Addenda to the amended Utility Model Act consist only of Article 1 (Enforcement Date) and Article 2. [5] The Addenda to the amended Utility Model Act contain no provision that separately states from when the amended wording of Article 81-3 of the Patent Act, which applies mutatis mutandis under Article 20, applies to utility model rights. [5]
• The amended Design Protection Act removes good cause from Article 84 and deletes paragraph (3). [5] It excludes the case in which the registration fee or the underpaid registration fee was intentionally not paid. [5] The period is 1 year from the later expiration date, and the amount is left to Prime Ministerial Decree. [5] The wording of Article 90(2), subparagraph 4, is also revised. [5]
• Article 2 of the Addenda to the amended Design Protection Act also provides that the amended provisions of Article 84 and Article 90(2) apply beginning with cases in which the grace period for late payment or the period for the payment of the underpaid registration fee expires on or after the date the Act enters into force. [5]

The amount to pay when reinstating a utility model right or restoring a design right is also not yet set. Article 8(10), subparagraphs 2 and 3, of the current Fee Regulation sets only the amount for reinstatement or restoration under the provisions that will be deleted (Article 81-3(3) of the Patent Act as applied mutatis mutandis under Article 20 of the Utility Model Act, and Article 84(3) of the Design Protection Act). That amount is an amount equal to twice the registration fee, and the Fee Regulation has no version scheduled to enter into force. [3]

As of 9 October 2026, the Ministry of Government Legislation lists no version of the Trademark Act (상표법) scheduled to enter into force. [5]

What applicants should do

• In general, when a missed payment for a Korean patent is found, we suggest first checking the expiration dates of the period for late payment and the period for payment of under-paid patent fees. The provisions that apply depend on whether that date is before 16 March 2027 or on or after it.
• For cases in which the expiration date is before 16 March 2027, we suggest not waiting for the amendment. Those cases are not covered by the amended provisions, and the Addenda contain no transitional measure.
• For cases in which the expiration date is on or after 16 March 2027, we also suggest recording how and on what date the missed payment was found. The amended provision excludes the intentional case, and the way to show this is not yet set.
• We suggest not relaxing annual fee management on the assumption that reinstatement is available. The period of limited effect and the non-exclusive license remain after the amendment.
• When including the cost of reinstatement in a budget, we suggest calculating it again with the amount set after the Prime Ministerial Decree is promulgated.

Please confirm the deadlines and amounts for an individual patent with your agent.

FAQ

How many provisions of the Patent Act change on 16 March 2027?

Two. They are Article 81-3 and Article 87(2), subparagraph 4. [1] Both concern the reinstatement of patent applications abandoned, and patent rights lapsed, because the patent fee was not paid. [1]

Do the amended provisions apply to a patent that has already lapsed?

They apply beginning with cases in which the period for late payment or the period for payment of under-paid patent fees expires on or after 16 March 2027 (Addenda, Art. 2). [1] The Addenda contain no transitional measure for cases in which the period expired before that day. [1]

How much is paid for reinstatement after the amendment?

It is not yet set. The amended Article 81-3(1) leaves the amount to Prime Ministerial Decree. [1] As of 9 October 2026, the Fee Regulation has no version scheduled to enter into force. [3]

Can a foreign patentee also request reinstatement under the amended provisions?

The person named in the amended paragraph (1) is “a person who intends to obtain registration of the grant of a patent, or a patentee”. [1] The amended provision contains no wording that limits the person to domestic individuals or small and medium enterprises. [1]

How DEFINE IP Law Firm handles this

At the post-registration stage, DEFINE IP Law Firm checks, for each case, the payment period for the patent fee and the expiration date of the period for late payment. When the law changes, we read the applicability provision in the Addenda and determine which provisions apply to each case. When subordinate statutes are promulgated, we check the amounts and the procedure again. For questions about the payment of patent fees and reinstatement for Korean patents, please write to contact@defineip.kr.

Sources

1. Patent Act (특허법), Act No. 21955, promulgated 15 September 2026, in force from 16 March 2027. Text of the amendment, statement of reasons for the amendment (provided by the Ministry of Government Legislation (법제처)), Articles 81-3 and 87, Addenda Arts. 1 and 2. https://www.law.go.kr/법령/특허법 (verified 9 October 2026)
2. Patent Act (특허법), Act No. 21134, in force from 11 November 2025. Articles 14, 81, 81-2, 81-3 and 87. https://www.law.go.kr/법령/특허법 (verified 9 October 2026)
3. 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. Article 8(10), list of versions by enforcement date. https://www.law.go.kr/법령/특허료등의징수규칙 (verified 9 October 2026)
4. Ministry of Intellectual Property (지식재산처), Enforcement Rules of the Patent Act (특허법 시행규칙), Prime Ministerial Decree No. 2115, in force from 14 May 2026, Article 55-2. Enforcement Decree of the Patent Act (특허법 시행령), Presidential Decree No. 35809, in force from 1 October 2025, Article 7-2(1), subparagraph 1 (m). Lists of versions by enforcement date of the two statutes. https://www.law.go.kr/법령/특허법시행규칙 (verified 9 October 2026)
5. Utility Model Act (실용신안법), Act No. 21953, and Design Protection Act (디자인보호법), Act No. 21951, promulgated 15 September 2026, in force from 16 March 2027. Text of the amendments, Addenda, Utility Model Act Articles 20 and 21, Design Protection Act Articles 84 and 90. List of versions by enforcement date of the Trademark Act (상표법). https://www.law.go.kr/법령/실용신안법 (verified 9 October 2026)
6. Patent Act (특허법), Act No. 18505, promulgated 19 October 2021, in force from 20 April 2022. Addenda Arts. 1 and 9. Version history at https://www.law.go.kr/법령/특허법 (verified 9 October 2026)
7. Act on Public Holidays (공휴일에 관한 법률), Act No. 21338, in force from 11 May 2026, Article 2. Act on National Holidays (국경일에 관한 법률), Act No. 12915, in force from 30 December 2014, Article 2. https://www.law.go.kr/법령/공휴일에관한법률 (verified 9 October 2026)