Introduction

In the Philippine legal system, the status of a child as legitimate or illegitimate carries significant implications for rights to inheritance, parental authority, use of surname, and other familial entitlements. Legitimation serves as a mechanism to elevate the status of an illegitimate child—typically one born out of wedlock—to that of a legitimate child through the subsequent valid marriage of the biological parents. This process is governed primarily by the Family Code of the Philippines (Executive Order No. 209, as amended), specifically Articles 177 to 182, along with administrative rules from the Philippine Statistics Authority (PSA) and Local Civil Registrars (LCRs).

The phrase "when parents are not legally separated" underscores a critical precondition: the parents must be legally capable of entering into a valid marriage with each other. Legal separation, as defined under Articles 55 to 67 of the Family Code, does not dissolve the marriage bond but merely allows spouses to live separately while addressing property, custody, and support issues. Thus, if either parent is only legally separated from a previous spouse (and not annulled or declared null and void), they remain married in the eyes of the law and cannot validly marry another person. This bars legitimation for a child born to one such parent and a new partner, as no subsequent valid marriage can occur. Legitimation is feasible only when parents are free from such impediments—meaning they are single, widowed, or have had prior marriages properly terminated through annulment, declaration of nullity, or (in rare cases involving foreigners) divorce recognized under Philippine law.

This article provides a comprehensive overview of legitimation in this context, including its legal basis, requirements, procedure, effects, potential challenges, and related considerations. It emphasizes that while legitimation occurs by operation of law upon the parents' marriage, "filing" refers to the administrative registration process to update civil records, which is essential for practical recognition.

Legal Basis and Historical Context

Legitimation traces its roots to civil law traditions, adapted in the Philippines through Spanish colonial influences and later refined in modern statutes. Prior to the Family Code's effectivity on August 3, 1988, legitimation under the Civil Code of 1950 (Republic Act No. 386) required not only subsequent marriage but also express acknowledgment of the child by the parents, often through a public document or will. The Family Code simplified this, making legitimation automatic upon valid marriage for children born after its enactment, provided the child was conceived and born outside a valid marriage.

Key provisions include:

Article 177: Children conceived and born outside of wedlock of parents who, at the time of conception, were not disqualified by any impediment to marry each other, may be legitimated.
Article 178: Legitimation takes place by the subsequent valid marriage between the parents. The annulment of a voidable marriage does not affect the legitimation.
Article 179: Legitimated children enjoy the same rights as legitimate children.
Article 180: Effects of legitimation retroact to the time of the child's birth.
Article 181: Legitimation may be impugned only if it is proven that marriage was impossible due to physical incapacity or other causes.
Article 182: Legitimation benefits children from void marriages if the parents later contract a valid marriage.

Amendments and related laws include Republic Act No. 9255 (2004), allowing illegitimate children to use the father's surname under certain conditions even without legitimation, and Republic Act No. 9858 (2009), extending legitimation to children conceived or born before August 3, 1988, under similar rules. Administrative Order No. 1, Series of 2004, from the Office of the Civil Registrar General details the registration process.

Importantly, if parents were impeded from marrying at the time of conception (e.g., one was married to another and only legally separated), the child cannot be legitimated unless that impediment is removed retroactively (e.g., through annulment that declares the prior marriage void ab initio). Legal separation alone, obtained via court decree under grounds like physical violence, adultery, or abandonment, does not remove the impediment, as per Article 63(1) of the Family Code, which states the marriage bond remains intact.

Requirements for Legitimation

For legitimation to apply when parents are not legally separated (i.e., free to marry without unresolved marital ties):

Illegitimate Status of the Child: The child must have been conceived and born while the parents were not married to each other. This includes children from common-law relationships, extramarital affairs (where one parent was married to someone else but that marriage is later terminated properly), or void marriages.
Subsequent Valid Marriage: The biological parents must marry each other validly after the child's birth. The marriage must comply with the Family Code (Articles 1-54), including capacity, consent, authority of solemnizing officer, license, and ceremony. If either parent had a prior marriage, it must have ended via death, annulment (for voidable marriages, e.g., lack of consent), or nullity declaration (for void marriages, e.g., bigamy, incest). Legal separation is insufficient, as it prohibits remarriage (Article 63).
No Impediment at Conception: At the time of the child's conception, the parents must not have been disqualified from marrying each other, except for age or relationship issues that are later cured. If an absolute impediment existed (e.g., existing marriage), legitimation requires that impediment's removal with retroactive effect.
Acknowledgment: While not always explicit, the marriage implies acknowledgment. For registration, parents affirm paternity/maternity in the affidavit.
Applicability to All Ages: Legitimation applies regardless of the child's age, even if the child is an adult or married. However, procedural nuances apply for adults (see below).

Children ineligible for legitimation include those adopted (as adoption confers legitimacy separately under Republic Act No. 8552) or those whose parents cannot marry due to permanent impediments (e.g., same-sex parents, though same-sex marriage is not recognized; or blood relations).

Procedure for Filing and Registration

Legitimation is automatic upon marriage, but to reflect it in official records and enjoy practical benefits (e.g., updated birth certificate), parents must register it administratively. No court petition is required unless there are disputes (e.g., impugning legitimacy). The process, overseen by the PSA and LCRs, is as follows:

Contract the Marriage: Parents marry at a church, court, or mayor's office, obtaining a marriage certificate.
Register the Marriage: Submit the marriage contract to the LCR of the marriage place within 15 days (or 30 days if abroad). Obtain certified copies.
Prepare the Affidavit of Legitimation: Both parents execute a notarized affidavit stating:
- They are the biological parents.
- The child was born illegitimate.
- They have since married.
- No legal impediments existed or were resolved. If the child is 18 or older, the child must co-sign the affidavit to consent, particularly for surname change.
Gather Supporting Documents:
- Child's birth certificate (original and photocopy).
- Parents' marriage certificate.
- Parents' birth certificates or IDs.
- Certificate of No Marriage (CENOMAR) from PSA to prove no prior unresolved marriages.
- If applicable, annulment/nullity decree or death certificate of previous spouse.
- If one parent is a foreigner, additional documents like legal capacity to marry.
Submit to the LCR: File at the LCR where the child's birth was registered. If born abroad, at the Philippine Consulate.
Annotation and Transmission: The LCR annotates the birth register, changes the child's status to "legitimated," and allows use of the father's surname (if desired). The updated record is transmitted to the PSA for endorsement.
Obtain Updated Birth Certificate: Request a PSA-certified copy with the annotation (e.g., "Legitimated by subsequent marriage of parents on [date] per Article 178, Family Code").

Timeline: Processing takes 1-3 months. Fees are minimal (around PHP 100-500 for affidavits and copies). Late registration may require additional affidavits explaining delays.

If the child's birth was not registered initially, register it first via late registration under Republic Act No. 3753, then proceed with legitimation.

Effects of Legitimation

Upon legitimation:

Retroactive Rights: The child is deemed legitimate from birth (Article 180), entitling them to:
- Legitimate filiation rights (Article 179), including support, succession (equal share with legitimate siblings), and parental authority.
- Use of the father's surname without court order.
Property and Inheritance: The child gains intestate succession rights equivalent to legitimate children, including legitime (compulsory share).
Citizenship and Other Benefits: If relevant, affects nationality claims (e.g., if one parent is foreign).
Irrevocability: Legitimation cannot be revoked except through impugnment proving impossibility (Article 181), with a 1-2 year prescription period.

Potential Challenges and Special Cases

If One Parent Was Previously Married: Ensure the prior marriage was terminated properly. Legal separation alone invalidates the subsequent marriage, making legitimation impossible. Seek annulment first (process under Articles 45-54, taking 1-3 years).
Adult Children: The child must participate in the affidavit. If they refuse surname change, it requires a separate petition under Rule 103 of the Rules of Court.
Deceased Parent: If one parent dies after marriage but before registration, the surviving parent can file with proof of marriage and paternity.
Foreign Elements: If marriage occurred abroad, register via Report of Marriage at the Consulate. Foreign judgments (e.g., divorce) must be recognized judicially under Article 26 of the Family Code if involving a Filipino.
Disputes: If paternity is contested, DNA testing may be required via court order. Impugnment actions must be filed timely.
Muslim Filipinos: Under the Code of Muslim Personal Laws (Presidential Decree No. 1083), similar rules apply, but divorce is allowed, potentially simplifying remarriage.
Common Pitfalls: Incomplete documents lead to denials. If the child was acknowledged as illegitimate earlier, ensure consistency.

Conclusion

Legitimation when parents are not legally separated promotes family unity and protects children's rights by removing the stigma of illegitimacy through a straightforward administrative process. It underscores the Philippine emphasis on marriage as the foundation of family. However, the inability to remarry post-legal separation highlights the need for annulment in complex cases. Parties are advised to consult legal professionals for personalized guidance, as this overview is for informational purposes and may evolve with jurisprudence or amendments. Relevant rulings, such as in Santos v. CA (1995) on retroactivity, further illustrate the doctrine's application.