(1) A person who intends to obtain a patent may claim priority on the invention described in the specification or drawings initially accompanying a separate application filed earlier (hereinafter referred to as "earlier application") for a patent or for registration of a utility model, on which he or she is entitled to the patent or registration of a utility model: Provided, That the foregoing shall not apply in the following cases: <Amended on Oct. 19, 2021>
1. Where the relevant patent application is filed one year after the filing date of the earlier application;
2. Where the earlier application is a divisional application under Article 52 (2) (including cases applied mutatis mutandis pursuant to Article 11 of the Utility Model Act) or splitting-off under Article 52-2 (2) (including cases applied mutatis mutandis pursuant to Article 11 of the Utility Model Act), or a converted application under Article 53 (2), or Article 10 (2) of the Utility Model Act;
3. Where the earlier application has been abandoned, invalidated, or withdrawn at the time the relevant patent application is filed;
4. Where the grant of the earlier application has been registered or where a decision or trial ruling to reject the patent application or to refuse to register a utility model becomes final and conclusive at the time the relevant patent application is filed.
(2) A person who intends to claim priority under paragraph (1) shall state his or her intention and indicate the earlier application in the patent application subsequently filed.
(3) In applying Article 29 (1) and (2), the main clauses of Article 29 (3) and (4), Articles 30 (1), 36 (1) through (3), 96 (1) 3, 98, 103, 105 (1) and (2), 129, and 136 (5) of this Act (including cases to which the aforesaid provisions shall apply mutatis mutandis pursuant to Article 132-3 (3) or 133-2 (4)), Articles 7 (3) and (4) and 25 of the Utility Model Act, and Articles 95 and 103 (3) of the Design Protection Act to the same invention as described in the specification or drawings initially accompanying the earlier application claiming the relevant priority, among inventions described in a patent application claiming priority under paragraph (1), the patent application filed subsequently shall be deemed to have been filed at the time the earlier application was filed. <Amended on Feb. 29, 2016>
(4) The main clause of Article 29 (3) or (4) of this Act or the main clause of Article 4 (3) or (4) of the Utility Model Act shall apply to an invention identical to the invention described in the specification or drawings initially accompanying the earlier application claiming the relevant priority, among inventions described in the specification or drawings accompanying the initial patent application claiming priority under paragraph (1), deeming that the earlier application claiming the priority is laid open at the time the relevant patent application is laid open or the patent is registered and published.
(5) In either of the following cases, paragraphs (3) and (4) shall not apply to an invention described in the specification or drawings initially accompanying the earlier application claiming priority, among inventions described in the specification or drawings initially accompanying the earlier application:
1. Where the earlier application contains a priority claim under paragraph (1);
2. Where the earlier application contains a priority claim under Article 4-D (1) of the Paris Convention for the Protection of Industrial Property.
(6) For the purposes of paragraph (4), Article 29 (7) shall not apply even where the earlier application falls under either of the following:
1. Where the earlier application is an international patent application deemed voluntarily withdrawn under Article 201 (4);
2. Where the earlier application is an international application for registration of a utility model deemed voluntarily withdrawn under Article 35 (4) of the Utility Model Act.
(7) A person who meets the requirements under paragraph (1) and claims priority may amend or add the priority claim within one year and four months from the filing date of the earlier application (referring to the earliest filing date, if at least two earlier applications have been filed).
(8) No earlier application on which the priority claim is based under paragraph (1) shall not obtain grant of a patent registered under Article 79: Provided, That this shall not apply where the priority claim based on the earlier application has been withdrawn. <Newly Inserted on Oct. 19, 2021>[This Article Wholly Amended on Jun. 11, 2014]