Das japanische Familienregister und grenzüberschreitende Rechtsverhältnisse

Abstract

The Japanese family register (koseki) is the only official register for the personal status and family relationships of the Japanese people. Because foreigners can never be registered there, no matter how long they live in Japan, the koseki serves as a register for Japanese citizenship as well. Each unit of the koseki consists of a married couple and unmarried children who have the same surname. When one of the children gets married, his name will be deleted from the old koseki and registered into a new one with his spouse. The koseki is administered by the ward office under the supervision of the prefecture office and the Ministry of Justice.

The koseki system, which is constructed in line with Japanese family institutions, functions well as long as Japanese law is to be applied. In cross-border cases, however, various kinds of problems emerge when a foreign law governs the legal relationship in question. The article points out several important problems to be taken into consideration in relation to conflict-of-law principles, such as determining the surname after the marriage, classification regarding international adoption, and limited competence of the ward office to implement certain control. The purpose of this survey is to show how the Japanese family register system should be reformed in the future to cope with modern issues of cross-border legal relations.