official copy of the family register
A certified copy of the family register (koseki) issued by a municipal office, used for legal and administrative procedures such as marriage, inheritance, or passport applications.
An official copy of the family register is required for passport applications.
I got a copy of my family register at the city hall.
I submitted a copy of the family register along with the marriage registration form.
The ward office issues copies of the family register after confirming identity.