In the Philippines, the surname of a child is governed by the Family Code and Republic Act No. 9255, which amended Article 176 of the Family Code. The process varies significantly depending on whether the child was born within a valid marriage (legitimate) or outside of one (illegitimate).
1. Illegitimate Children: The Path of RA 9255
Under the original Family Code, illegitimate children were required to use the mother’s surname. However, Republic Act No. 9255 now allows illegitimate children to use the surname of their father, provided the father has formally recognized the child.
Criteria for Changing the Surname
The father must have acknowledged paternity through any of the following:
- Affidavit of Admission of Paternity (AAP): A standalone sworn statement.
- Private Handwritten Instrument (PHI): A document written and signed by the father clearly admitting paternity.
- Birth Certificate Signature: The father signed the "Informant" section or the back of the Birth Certificate at the time of registration.
The Requirements
To effect the change at the Local Civil Registry (LCR), the following are typically required:
- Affidavit to Use the Surname of the Father (AUSF): This is a sworn statement executed by the mother (if the child is under 7), the child with the mother's attestation (if between 7 and 17), or the child (if of age).
- Certified True Copy of the Birth Certificate.
- Proof of Paternity (AAP, PHI, or the signed birth certificate).
- Certificate of Registration (issued by the LCR after the AUSF is filed).
2. Legitimate Children: The Rule of Immutability
If a child is born during a valid marriage, they are considered legitimate and must use the father's surname by law. Generally, a legitimate child cannot change their surname to that of a biological father if that biological father is someone other than the legal husband, unless a court first rules on the child's status.
- Presumption of Legitimacy: A child born during a marriage is presumed to be the child of the husband.
- Impugning Legitimacy: To change the surname in this context, a judicial action to "impugn the legitimacy" of the child must be successful. Only then can the child be registered as the illegitimate child of the biological father.
3. Judicial Petition for Change of Name
If the administrative process under RA 9255 is not applicable (e.g., if there is a dispute or the civil registry denies the application), a Petition for Change of Name must be filed under Rule 103 of the Rules of Court.
Grounds for Judicial Change
Courts generally grant a change of surname to the biological father's name if:
- The name is ridiculous or tainted with dishonor.
- The change is necessary to avoid confusion.
- The child has been continuously using the father’s surname and is publicly known by it.
- The Best Interest of the Child: This is the paramount consideration. If using the biological father’s name provides the child with legal clarity and stability, the court may favor it.
4. Legitimation by Subsequent Marriage
If the biological parents were not married at the time of birth but later enter into a valid marriage, the child can undergo Legitimation.
- Effect: The child’s status is raised to "Legitimate."
- Process: The parents file an Affidavit of Legitimation at the LCR where the birth was registered.
- Result: A new birth certificate is issued (with a marginal annotation), and the child automatically takes the father’s surname as a matter of right.
Summary Table: Administrative vs. Judicial
| Method | Legal Basis | Venue | Primary Document |
|---|---|---|---|
| Administrative (RA 9255) | Illegitimate status | Local Civil Registry | AUSF & Admission of Paternity |
| Legitimation | Subsequent Marriage | Local Civil Registry | Affidavit of Legitimation |
| Judicial Petition | Rule 103 / Rule 108 | Regional Trial Court | Court Order/Decree |
Important Legal Limitations
- Consent: If the child is 18 years or older, they must execute the AUSF themselves.
- Retroactivity: A change of surname does not automatically grant rights of inheritance unless the recognition of paternity is legally sufficient under the Civil Code.
- Annotation: Note that in administrative changes, the original birth certificate is not "erased." Instead, a marginal annotation is made on the document to reflect the change in surname.