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Acknowledging paternity of a child is a legal act in which a man acknowledges that he is the father of a child.
If the mother is married when she gives birth, the husband is automatically presumed to be the father of the child; he does not need to officially acknowledge paternity. Even if another man claims to be the biological father of the child, the husband’s relationship as legal father overrides and it is necessary to file a petition contesting paternity to change this state of affairs.
If the mother is not married at the time of birth, the man who is understood to be the biological father must explicitly recognise any children born out of wedlock. He can acknowledge paternity either before or after the birth.
It is not possible to recognise a child if another man has already done so. In such a case, it is necessary to file a petition to contest recognition.
If you are a swiss citizen or if you live in Switzerland you can acknowledge paternity in any civil register office.
If you are not a swiss citizen or if you live abroad, you can acknowledge paternity at the register office where your child was born or at the usual place of residence; at the place of residence or place of origin of the child’s mother; or, if you are a Swiss citizen, at your place of origin.
Usually you only have to produce a piece of identification and proof of address. The civil register office (for details, see above) will tell you if you need to bring any other documents along.
Once paternity has been officially acknowledged, the legal relationship between the father and his child is established from the child’s date of birth, and retroactively if parentage was established after birth. The father and child may then exercise their rights and reciprocal duties (custody, obligation to provide maintenance, duty of assistance, inheritance rights, etc.)
If the parents are not married, an application must be made in order for the parents to be granted joint custody. If it is the parents’ first child, they may choose whether the child should take the mother's maiden name and or the father’s surname. Any further children that the parents have together will bear the same name.
If the mother is a foreign national and the father acknowledging paternity is Swiss, the child obtains Swiss citizenship from the father.
Questions regarding acknowledgment, nationality and the name of the child can be addressed to the civil register office where the acknowledgement took place, or to the appropriate child and adult protection authority.
A non-Swiss father who has acknowledged paternity of a child in Switzerland must personally ensure that he also does so in his country of origin. Swiss civil register offices do not automatically inform authorities abroad when someone acknowledges paternity, except for those in Germany, Austria and Italy, countries with which an agreement has been signed.
Contact the embassy or consulate of the country concerned to find out what the formal requirements are.