In the Philippines, the surname an illegitimate child carries is governed by the Family Code, as significantly amended by Republic Act No. 9255. While the default rule is that illegitimate children shall use the surname of their mother, the law provides a clear mechanism for them to use their father's surname, provided certain legal requirements are met.
For an adult illegitimate child (aged 18 and above), this process centers on a specific legal document: the Affidavit to Use the Surname of the Father (AUSF).
1. The Legal Framework: R.A. 9255
Before the enactment of R.A. 9255 in 2004, illegitimate children were strictly required to use their mother's surname. The amendment to Article 176 of the Family Code now allows these children to use the father’s surname if:
- The father has acknowledged the child through an Affidavit of Admission of Paternity (AAP); or
- The father has acknowledged the child through a Private Handwritten Instrument (PHI).
2. Who Executes the AUSF?
The person responsible for executing the AUSF depends on the age of the child at the time of application:
- 7 years old and below: The mother or guardian executes the AUSF.
- Between 7 and 17 years old: The child executes the AUSF with the "attestation" of the mother or guardian.
- 18 years old and above (Adult): The adult child executes the AUSF personally. No attestation from the mother is required.
3. Essential Requirements for Adults
For an adult illegitimate child to successfully transition to using the father's surname, the following documents are generally required by the Local Civil Registrar (LCR):
A. Proof of Paternity
The father must have recognized the child. This is proven by:
- A signed "Admission of Paternity" on the back of the Certificate of Live Birth (COLB); or
- A separate Affidavit of Admission of Paternity (AAP); or
- A Private Handwritten Instrument (PHI), which is a document written and signed by the father acknowledging he is the parent.
B. The AUSF
The adult child must execute a sworn affidavit stating their desire to use the father's surname. This document must be notarized.
C. Supporting Documents
- PSA Birth Certificate of the child.
- Valid IDs of the child.
- CENOMAR (Certificate of No Marriage) of the parents (often required to verify the illegitimate status).
4. The Registration Process
The process is administrative, meaning it is handled through the civil registry rather than the courts.
- Filing: The documents are filed at the LCR where the birth was originally registered. If the birth occurred abroad, it is filed at the Philippine Consulate or the Department of Foreign Affairs (DFA).
- Verification: The Civil Registrar examines the authenticity of the admission of paternity and the AUSF.
- Annotation: The Civil Registrar does not issue a brand-new birth certificate. Instead, they make an annotation on the original birth certificate.
- Issuance: Once registered, the PSA will issue a certified copy of the birth certificate with the side annotation stating that the child is now authorized to use the father's surname under R.A. 9255.
5. Key Distinctions and Limitations
| Feature | Details |
|---|---|
| Legitimation vs. AUSF | AUSF only changes the surname. It does not change the child's status from "Illegitimate" to "Legitimated." Legitimation only occurs if the parents were not disqualified from marrying at the time of conception and subsequently marry. |
| Middle Names | Under current regulations, an illegitimate child who uses the father's surname generally uses the mother's surname as their middle name. |
| Retroactivity | R.A. 9255 applies to all illegitimate children born during the effectivity of the Family Code (August 3, 1988) onwards. |
6. Important Notes for Adults
- Personal Choice: For an adult, the decision to use the father’s surname is a personal right. Even if the father has acknowledged paternity, the adult child is not forced to change their surname; they may choose to continue using the mother’s surname.
- Documentary Consistency: Once the AUSF is registered and the PSA birth certificate is annotated, the adult child must update all other government records (Passport, PRC, Driver’s License, SSS) to ensure consistency.
- Legal Effects: Using the father's surname does not automatically grant increased successional (inheritance) rights beyond what is already provided to acknowledged illegitimate children by the Civil Code. It is primarily a change in the child's public identity.
Final Note: While the process is administrative, if the father refuses to acknowledge paternity or is deceased without leaving a PHI, the child may need to file a judicial petition for Compulsory Recognition in court before the AUSF can be utilized.