When a foreign woman gives birth in Japan while unmarried or when both parents are foreign citizens, the act of submitting a birth notification to the Japanese municipal office does not automatically grant nationality to the child. Additionally, some foreign diplomatic missions may not recognize a birth certificate for a child born in Japan because some nations follow the principle of place of birth or discriminate against children born out of marriage.

Nationality is considered a fundamental right and is crucial for a child's identity and state protection. Every child has the right to citizenship according to Article 7 of the Convention on the Rights of the Child.

However, just because a child's nationality is listed on their residency card, it does not necessarily mean they have acquired it if notice has not been made to the parent's home country. Failure to report in the home country may have negative consequences, such as difficulty obtaining a passport or going through the naturalization or marriage process. This may cause a loss of connection to the child's home country and could lead to statelessness and difficulties for future generations.