Who is father of child born within 300 days of divorce?

What the Law Says

Japanese civil law establishes a legal presumption of paternity for children born shortly after divorce. This presumption protects family stability and clarifies parental responsibility from birth.

Article 772 of the Japanese Civil Code states that a child conceived or born during marriage is presumed to be the child of the husband. Importantly, this presumption extends to a child born within 300 days after the dissolution of marriage — including divorce.

This means that even if the couple is no longer married at the time of birth, the former husband is legally treated as the father unless he formally denies paternity through proper legal procedure.

To deny paternity, the former husband must file a 'denial of paternity' action in Family Court within one year from when he becomes aware of the birth — and no later than one year from the date of divorce, whichever comes first. However, under Article 774, he must file within 14 days of learning of the birth if he knew or should have known about it earlier.

Statutory Text

A child conceived or born during marriage is presumed to be the child of the husband.

— Civil Code, Art. 772 — Presumption of legitimacy

Statutory Text

The husband may deny paternity only by filing an action for denial of paternity with the family court within one year from the time he becomes aware of the birth of the child; provided, however, that such action may not be filed more than one year from the date of dissolution of the marriage.

— Civil Code, Art. 774 — Period for denial of paternity

What to Do

Sources