Nature of Paternity and Filiation
Filiation is the civil status connecting a child to the child's parents, while paternity identifies the legal relation between the child and the father. It is not a mere biological fact because the law attaches to it name, support, parental authority, legitime, intestate succession, nationality-related records, and family status.
The Family Code classifies filiation by nature as legitimate or illegitimate. Adoptive filiation is juridical rather than biological, and legitimation is a statutory conversion of an existing illegitimate status into legitimate status by the subsequent valid marriage of qualified parents.
Status is indivisible against the world. A person cannot be legitimate for support but illegitimate for succession, and a civil registry entry cannot privately alter status unless the substantive requisites for recognition, legitimacy, or legitimation exist.
| Classification | Source of status | Principal consequence |
|---|---|---|
| Legitimate child | Conception or birth during a valid marriage, or a special statutory rule treating the child as legitimate | Full rights to surname, support, legitime, and succession as a legitimate child |
| Illegitimate child | Conception and birth outside a valid marriage, unless a statute provides otherwise | Rights recognized by law, but with a legitime generally equal to one-half that of a legitimate child |
| Legitimated child | Subsequent valid marriage of parents qualified to legitimate the child | Same rights as a legitimate child, with effects retroacting to birth |
Legitimate Filiation
A child conceived or born during the marriage of the parents is legitimate. The rule protects family stability by tying legitimacy to the marriage bond rather than to later suspicions, private declarations, or collateral attacks.
The phrase conceived or born is important. A child conceived before the marriage but born during the marriage is legitimate, and a child conceived during the marriage but born after its termination may remain legitimate if the statutory presumptions on gestation apply.
A child conceived through artificial insemination of the wife is legitimate when both spouses authorized or ratified the procedure in a written instrument executed and signed before the child's birth and recorded with the civil registry together with the birth certificate. The law treats consent as the controlling juridical act because the child is born into the marital family by the spouses' prior written acceptance.
Children conceived and born outside a valid marriage are illegitimate unless the Family Code or another statute expressly treats them as legitimate. Thus, children of void marriages are generally illegitimate, but children covered by special Family Code provisions on certain judgments of nullity and subsequent marriages retain legitimate status when the statutory conditions are present.
Presumptions Around Termination of Marriage
The law uses gestational presumptions to resolve uncertainty when a child is born near the beginning or end of a marriage. These presumptions operate unless competent proof places the child's filiation outside the statutory rule.
| Situation | Presumed status or filiation |
|---|---|
| Child born after one hundred eighty days following the celebration of the marriage | Presumed legitimate even if the mother declares otherwise or is convicted of adultery |
| Child born within three hundred days after termination of the marriage | Presumed conceived during the terminated marriage, subject to the rules on impugning legitimacy |
| Mother remarries within three hundred days after termination of the former marriage and the child is born before one hundred eighty days from the second marriage | Presumed conceived during the former marriage if born within three hundred days from its termination |
| Mother remarries within three hundred days after termination of the former marriage and the child is born after one hundred eighty days from the second marriage | Presumed conceived during the second marriage even if born within three hundred days from termination of the former marriage |
| Child born after three hundred days following termination of the marriage | Legitimacy or illegitimacy must be proved by the party alleging it |
The mother's statement that the child is not her husband's child does not defeat legitimacy. The mother's adultery also does not by itself defeat legitimacy because the law requires proof that excludes the husband, not merely proof that another man had access.
Impugning Legitimate Filiation
Legitimacy may be attacked only through a direct action to impugn it and only on grounds recognized by the Family Code. The action is restrictive because legitimacy is a civil status protected not only for the child but also for the family and society.
The husband is the ordinary party entitled to impugn the legitimacy of a child born to his wife. Other persons cannot ordinarily mount a collateral attack by simply alleging that the husband is not the biological father.
- Physical impossibility of access. The husband must have been physically incapable of sexual intercourse with the wife during the first one hundred twenty days of the three hundred days immediately preceding birth, or the spouses must have been living separately in a manner making intercourse impossible, or a serious illness must have absolutely prevented intercourse.
- Biological or scientific impossibility. Scientific evidence may show that the child could not have been that of the husband, subject to the special rule on validly consented artificial insemination.
- Defective consent to artificial insemination. If the child's legitimacy rests on artificial insemination, legitimacy may be impugned when the husband's consent was obtained through mistake, fraud, violence, intimidation, or undue influence.
Physical separation is not enough if access remained possible. Adultery, rumors, resemblance to another man, or an unsupported entry in the civil registry does not replace the statutory grounds.
The action is subject to short prescriptive periods counted from knowledge of the birth or, when the birth was concealed, from knowledge of its recording in the civil register. The period is one year if the husband or his heirs reside in the same city or municipality where the child was born or recorded, two years if they reside elsewhere in the Philippines, and three years if they reside abroad.
The heirs of the husband may impugn legitimacy only when the husband died before the expiration of the period for filing the action, when he died after filing the action, or when the child was born after his death. Their right is derivative and cannot be broader than the right granted to the husband.
Once the period to impugn lapses, legitimacy becomes conclusive for civil purposes. Later biological certainty cannot revive a barred action because the law values finality of status over indefinite challenges to family relations.
Proof of Filiation
Filiation may be proved by primary evidence that directly acknowledges status, or by secondary evidence showing consistent treatment as a child. The choice of evidence affects not only the strength of the claim but also the period within which an action must be brought.
| Mode of proof | Legal significance |
|---|---|
| Record of birth appearing in the civil register | Primary proof when the record itself legally binds the parent whose filiation is asserted |
| Final judgment | Primary proof because the status has already been adjudicated in an adversarial proceeding |
| Admission in a public document | Primary proof when the parent acknowledges the child in a notarized or otherwise public instrument |
| Admission in a private handwritten instrument signed by the parent | Primary proof because the parent's personal writing and signature supply reliable acknowledgment |
| Open and continuous possession of the status of a child | Secondary proof based on consistent acts of recognition, support, care, reputation, and family treatment |
| Other evidence allowed by procedural rules and special laws | Secondary proof that may include letters, photographs, school records, medical records, testimony, or scientific evidence when competent and relevant |
A birth certificate is powerful only when it contains an acknowledgment attributable to the parent concerned. If the father's name was supplied by the mother, by the informant, or by the registrar without the father's signature or legally sufficient admission, the entry does not by itself prove paternity against him.
An admission in a public document need not be contained in a birth record. It may appear in an affidavit, deed, pleading, settlement, or other public instrument where the parent clearly and personally recognizes the child.
A private handwritten instrument must be treated carefully. The reliability comes from handwriting and signature attributable to the parent, not from a printed form merely carrying the alleged parent's name.
Open and continuous possession of status requires more than occasional affection or isolated financial help. It is shown by a pattern of conduct in which the parent and the family publicly and consistently treat the child as a child, such as by support, schooling, correspondence, cohabitation, reputation in the community, and inclusion in family dealings.
Scientific evidence may assist in proving or disproving biological relationship, but it does not automatically settle every civil consequence. The legal status of a child still depends on the applicable rules on legitimacy, prescription, recognition, and the proper parties.
Actions to Claim Filiation
An action to claim legitimate filiation may be brought by the child during the child's lifetime. If the child dies during minority or while insane, the right is transmitted to the heirs, who must act within the statutory period from the child's death.
For illegitimate children, the evidence used determines the time limit. If filiation is established through the record of birth, a final judgment, or an admission in a public document or private handwritten instrument, the action follows the period for claiming legitimate filiation. If the action relies on open and continuous possession of status or other secondary evidence, it must be brought during the lifetime of the alleged parent.
This distinction prevents stale claims based on testimonial or circumstantial evidence after the alleged parent can no longer personally admit, deny, explain, or contest the relationship. It also preserves claims supported by written or adjudicated recognition because those proofs are less dependent on memory.
Rights of Legitimate Children
Legitimate children have the right to bear the surnames of the father and mother in conformity with law. Their surname reflects legal family membership, not merely biological ancestry.
They are entitled to support from their parents and, in proper cases, from other relatives obliged by law. Support includes everything indispensable for sustenance, dwelling, clothing, medical attendance, education, and transportation in keeping with the family's resources and the child's needs.
Legitimate children are compulsory heirs of their parents. Their legitime is protected against donations, wills, and other dispositions that impair the reserved portion fixed by succession law.
Legitimate filiation also affects parental authority. As a rule, the father and mother jointly exercise parental authority over their unemancipated legitimate children, with the child's welfare controlling in case of disagreement requiring judicial intervention.
Illegitimate Filiation
An illegitimate child is one conceived and born outside a valid marriage, unless the child is made legitimate by a specific statutory rule. The status does not erase legal rights, but it changes the rules on surname, parental authority, legitime, and certain succession consequences.
Illegitimate children establish filiation by the same kinds of evidence used by legitimate children. The critical practical difference is that claims based on secondary evidence must be filed during the lifetime of the alleged parent.
An illegitimate child is generally under the parental authority of the mother, even when the father recognizes the child. Recognition by the father creates civil effects such as support, succession rights, and possible use of the father's surname, but it does not automatically transfer parental authority from the mother.
The legitime of an illegitimate child is generally one-half of the legitime of a legitimate child. This rule must be coordinated with the legitimes of the surviving spouse, legitimate children, and other compulsory heirs under succession law.
Illegitimate children may inherit by intestacy from their parents and from their own descendants, but the Civil Code barrier between the legitimate family and the illegitimate child limits intestate succession between an illegitimate child and the legitimate relatives of the parent. Testamentary dispositions may still benefit an illegitimate child if they do not impair legitimes and do not violate prohibitions on donations or succession.
Use of the Father's Surname Under Republic Act No. 9255
Republic Act No. 9255 amended the rule on surnames by allowing an illegitimate child to use the surname of the father when the father has expressly recognized the child. The law permits use of the paternal surname; it does not make the child legitimate.
Recognition for this purpose may appear in the record of birth, in an admission in a public document, or in a private handwritten instrument signed by the father. The acknowledgment must be attributable to the father because the use of his surname rests on his recognition of paternity.
The child's use of the father's surname does not erase the mother's parental authority over an illegitimate child. It also does not equal legitimation, does not by itself create a valid marriage between the parents, and does not increase the child's legitime to that of a legitimate child.
Administrative annotation of the father's surname in the civil registry is evidentiary and record-keeping in character. If paternity is disputed, the existence and effect of recognition may still require judicial determination.
The father who has recognized an illegitimate child may bring an action before the regular courts to prove non-filiation during his lifetime. This remedy addresses erroneous or disputed recognition, but it must be reconciled with the rules protecting civil status, due process, and the child's rights.
Legitimation
Legitimation is the legal process by which an illegitimate child becomes legitimate by operation of law upon the subsequent valid marriage of the child's parents. It is different from recognition because recognition proves paternity or maternity, while legitimation changes the child's civil status.
The basic requisites are: the child was conceived and born outside wedlock; the parents, at the time of conception, were not disqualified by any legal impediment to marry each other, except the age-only impediment covered by Republic Act No. 9858; and the parents later entered into a valid marriage.
Republic Act No. 9858 expanded legitimation by covering children whose parents were disqualified from marrying each other at the time of conception solely because either or both parents were below eighteen years of age. The amendment recognizes that minority alone should not permanently prevent the child from becoming legitimate when the parents later validly marry.
Other impediments remain fatal to legitimation. If, at the time of conception, either parent was married to another person, or the parents were within a prohibited degree of relationship, the child cannot be legitimated by the parents' later marriage after the impediment disappears.
The subsequent marriage must be valid. A void marriage cannot legitimate because the law requires a legally effective marriage as the operative act that changes status.
Legitimation takes effect by operation of law from the celebration of the valid subsequent marriage, but its civil effects retroact to the child's birth. Civil registry annotation records the status; it does not create legitimation when the requisites are absent.
A legitimated child enjoys the same rights as a legitimate child. The child may use the surname and claim support, parental authority consequences, legitime, and succession rights as a legitimate child.
Legitimation also benefits the descendants of a child who died before the parents' subsequent marriage. The law preserves the transmission of benefits to the child's line because the status would have belonged to the child had the child survived.
Legitimation may be impugned only by those whose rights are prejudiced and only within the statutory period from the accrual of their cause of action. The usual grounds are absence of a qualifying parent-child relationship, lack of a valid subsequent marriage, or the existence of a disqualifying impediment at the time of conception other than the minority exception.
Civil Registry and Status
The civil registry records facts and legal acknowledgments, but it does not create filiation contrary to law. A record may be corrected to reflect true civil status only through the procedure required for the nature of the correction.
Clerical or typographical errors may be handled administratively when the law allows, but substantial changes affecting legitimacy, paternity, maternity, or surname require observance of due process and notice to persons whose rights may be affected. Filiation cannot be changed by a private agreement between adults when the child's legal status and succession rights are involved.
A child may have evidence of biological paternity without having the civil status of a legitimate child. Conversely, a child protected by the presumption of legitimacy may retain legitimate status even when later allegations point to a different biological father, if the law bars or rejects the action to impugn.
Comparative Effects
| Aspect | Legitimate child | Illegitimate child | Legitimated child |
|---|---|---|---|
| Surname | Uses the surnames of the father and mother according to law | Generally uses the mother's surname, but may use the father's surname upon express recognition under Republic Act No. 9255 | Uses surname rights of a legitimate child after legitimation |
| Parental authority | Generally joint parental authority of father and mother | Generally under the mother's parental authority | Governed by rules for legitimate children |
| Support | Full right to support from obliged relatives under the Family Code | Right to support from parents and other persons obliged by law, subject to status rules | Same support rights as a legitimate child |
| Legitime | Full legitime of a legitimate child | Generally one-half of the legitime of a legitimate child | Full legitime of a legitimate child, with effects retroacting to birth |
| Conversion of status | No conversion needed | May be legitimated if all requisites exist | Already converted to legitimate status by operation of law |
Doctrinal Synthesis
Paternity and filiation turn on the interaction of biological fact, marital status, statutory presumptions, written recognition, and procedural time limits. Biology matters, but it does not override every rule protecting legitimacy, finality, and the child's civil status.
Legitimate status is favored when the child is conceived or born within marriage, and it can be defeated only by the proper party, on statutory grounds, within the statutory period. Illegitimate status carries enforceable rights, including support and succession, but recognition and surname use do not transform it into legitimacy.
Legitimation is the principal statutory bridge from illegitimacy to legitimacy. It requires both qualifying parentage at conception and a later valid marriage, with Republic Act No. 9858 removing minority as the sole disqualifying impediment.
The most reliable proof of filiation is an official record, final judgment, or personal written admission by the parent. When proof rests on conduct, reputation, or other circumstantial evidence, the law demands timely action while the alleged parent is still alive.