Reacquisition of nationality by notification

• Reacquisition by notification, Art. 17(1): a person who lost Japanese nationality under Art. 12 (foreign-born dual, reservation-failure) and is under 18, having a domicile in Japan, may reacquire Japanese nationality by notification to the Minister of Justice — taking effect at the time of notification (Art. 17(3)). The age ceiling was 20 before 2022. - Reacquisition by notification, Art. 17(2): a person who, after receiving an Art. 15(2) demand, lost Japanese nationality under Art. 15(3) may reacquire it by notification within 1 year of learning of the loss, provided they meet Art. 5(1)(v) (no/renounced foreign nationality); a natural-disaster/no-fault grace extends the period to 1 month from when notification becomes possible. - A person who lost Japanese nationality under Art. 12 (reservation-failure) and is under 18 may reacquire Japanese nationality by notification to the Minister of Justice if domiciled in Japan (Art. 17(1)); a person who lost under Art. 15(3) (demand-failure) may reacquire by notification within 1 year of knowing of the loss if they meet Art. 5(1)(v) (Art. 17(2)).

• Where the person effecting a nationality act — Art. 3(1) acknowledged-children acquisition, Art. 17(1) reacquisition, a selection declaration, or an Art. 13 renunciation notification — is under 15 years of age, the act is performed by the statutory agent (法定代理人) on the person's behalf (Nationality Act Art. 18).

• Where nationality is acquired by notification under Art. 3(1) (acknowledged children) or Art. 17(1)/(2) (reacquisition), the nationality-acquisition notification for koseki entry must be filed within 1 month of acquisition, or 3 months if the person is abroad on that date (Family Register Act Art. 102). - Where nationality is acquired under Nationality Act Art. 3(1) (acknowledged children) or Art. 17(1)/(2) (reacquisition by notification), the nationality-acquisition notification to the koseki must be filed within 1 month of acquisition, or 3 months if the person is abroad on the acquisition date (Family Register Act Art. 102(1)).

Primary legal authorities: Nationality Act Art.17. Status: Operative (—present). Administering authority: Ministry of Justice (法務省), Civil Affairs Bureau, via the Legal Affairs Bureaus (法務局); consular missions (外務省) for notifications/applications filed abroad. A person who lost nationality under Art.12 (reservation-failure) and is under 18 with a Japanese domicile may reacquire by notification (Art.17(1)); a person who lost under Art.15(3) may reacquire if they have/relinquish no other nationality (Art.17(2)).