Inheritance Share of Illegitimate Children in the Philippines
(Comprehensive Legal Guide as of 21 April 2025)

1. Foundations: Where the Rules Come From

Source	Key Provisions on Illegitimate Children
Civil Code of the Philippines (1950)	Book III on Succession, esp. Arts. 887, 888, 895, 964–1016; Art. 992 (“barrier rule”).
Family Code of the Philippines (E.O. 209, 1987)	Arts. 172–176 (proof of filiation); Arts. 887 & 895 (compulsory heirs and legitimes); abolished the “natural/spurious” distinction and fixed the ½ ratio.
Special Laws	• RA 9858 (2009) – legitimation of children born to parents later married under Article 34 of the Family Code. • RA 9255 (2004) – use of father’s surname after acknowledgment. • RA 11222 (2019) – Simulated Birth Rectification Act (treats rectified child as legitimate).
Tax & Procedure	NIRC (as amended), Rules of Court (Rule 73 et seq.) on settlement and guardianship.
Jurisprudence	Diaz v. IAC (1989); Cabural v. Heirs of Cabural (2005); Aquino v. Aquino (G.R. No. 208912, 2021); Heirs of Malate v. Gamboa (G.R. No. 231112, 2022) – confirmed continued effect of Art. 992.

2. Who Is an “Illegitimate Child”?

An illegitimate child is one conceived and born outside a valid marriage (Art. 165, Family Code). The Family Code erased the old Civil‑Code categories (“natural,” “spurious,” etc.); now all illegitimate children enjoy identical succession rights subject to the limits below.

Recognition/filiation may be proved by: birth certificate signed by the father; a written/admitted acknowledgment; acts of open and continuous possession of status; or DNA evidence. (Arts. 172–175, FC; Republic v. Caguioa, 2022).

3. Two Pathways to Inheritance

Path	Governing Rules	When Applied
Intestate succession	Arts. 960 ff., Civil Code	No valid will, or will does not dispose of entire estate.
Testate succession	Testator’s will + compulsory‑heir limits (Art. 885)	There is a valid will; legitimes must still be respected.

In both paths, illegitimate children are compulsory heirs (Art. 887), meaning their legitime cannot be impaired by donations or legacies.

4. Legitime: the “½‑Rule” in a Nutshell

“The legitime of each illegitimate child shall be one‑half of the legitime of a legitimate child.”
— Art. 895, Civil Code (as amended by the Family Code)

Example (simple estate, Php 6 million)

Heirs	No.	Share of estate	Basis
Legitimate child	1	₱2 million	Legitime (½ of estate because no spouse)
Illegitimate child	1	₱1 million	½ of legit child’s legitime
Free portion	—	₱3 million	Disposable by will; if none, follows intestacy proportionally.

When several illegitimate children exist, they divide their ½‑share among themselves pro rata (Art. 895, ¶2).

5. Intestate Succession Scenarios

Both legitimate and illegitimate descendants.
Legitimate children & surviving spouse inherit in equal shares; illegitimate children receive ½ of each legitimate heir’s share, collectively.
Only illegitimate descendants.
They inherit as if legitimate (full estate pro rata) because there is no competition with legitimate issue (Art. 991).
Illegitimate child vs. legitimate ascendants.
If the deceased leaves no legitimate children but leaves legitimate parents/grandparents, illegitimate child and legitimate parents share the estate equally (Art. 990).
“Barrier rule” (Art. 992).
Illegitimate children cannot inherit intestate from the legitimate relatives of their parents, nor these relatives from them. Courts have consistently upheld this as of 2025. Aquino v. Aquino reaffirmed that repeal requires Congress.

6. Testate Succession & Legitimes

A testator may distribute the free portion (the part left after satisfying legitimes) to anyone. Because illegitimate children are compulsory heirs, a will still must leave them at least ½ of a legitimate child’s legitime. Failure renders the will partly void.

7. Representation & Survivorship

Downward representation. Illegitimate descendants may represent their pre‑deceased illegitimate parent in inheriting from a grandparent (Art. 902), but cannot represent through a legitimate line because of Art. 992.
Surviving spouse of the decedent is a separate compulsory heir; her legitime is compared with both classes of children per Art. 892.

8. Legitimation, Adoption & Subsequent Marriage

Mechanism	Resulting Status	Effect on Succession
Legitimation under RA 9858 (parents free to marry and later do so)	Child becomes legitimate retroactively to birth.	Now entitled to the full legitime of a legitimate child; ½‑rule no longer applies.
Simulated‑birth rectification (RA 11222) after compliance	Child is deemed legitimate from decree date.	Legitime becomes equal to legitimate child prospectively.
Adoption (RA 11642, 2022 Domestic Admin Adoption Law)	Adoptee is legitimate child of adopter; legal tie with biological parents is, in effect, cut.	Inherits from adopter as legitimate; biological link severed (save in cases of step‑parent adoption under Art. 189, FC).

9. Waiver, Renunciation, Compromise

Illegitimate children may not waive their legitime in advance (void under Art. 739). After the estate is open and their shares fixed, they may renounce or compromise, but minors require court approval.

10. Tax & Procedural Notes

Estate tax is imposed on the estate, not the heirs; shares of illegitimate children are included in computing the gross estate.
Extra‑judicial settlement is possible only if (a) no debts, (b) all heirs of age and agree; minors require guardianship.
Publication of the settlement and submission of a bond are mandatory even when illegitimate children are the only heirs.
Prescription: An action to demand legitime prescribes in 10 years (Art. 1144, Civil Code) from settlement or repudiation; if fraud is later discovered, 4 years from discovery (Art. 1391).

11. Common Pitfalls & Practical Tips

Failure to prove filiation early. File an action under Art. 173 within four years after reaching majority if filiation is not in the birth certificate.
Ignoring the “barrier rule.” Illegitimate heirs often sue collateral relatives in intestacy, only to be dismissed. If the decedent was legitimate, consider testate solutions (a will or donations) to break the barrier.
Assuming equality under “illegitimate = legitimate” bills. Several measures to repeal Art. 992 are pending, but none have been enacted as of April 2025.
Overlooking legitimation routes. If parents later marry—or can marry under Art. 34—file legitimation: it instantly upgrades shares.
Signing an extra‑judicial settlement that omits illegitimate children. This is voidable for fraud; illegitimate children can annul it within four years of discovery.

12. At a Glance: Quick Questions

Question	Short Answer
Can a will disinherit an illegitimate child?	Only on grounds in Art. 919 (serious offenses). Otherwise void.
Is DNA testing mandatory?	No, but it is the strongest modern evidence of filiation.
Do illegitimate grandchildren represent their parent against a legitimate grandparent?	Yes, if the intervening parent was also illegitimate (Art. 902).
Does using the father’s surname (RA 9255) make the child legitimate?	No; status remains illegitimate.
If a legitimate and an illegitimate child die together, who inherits?	Apply right of accretion or representation depending on survivorship evidence; absent such, assume simultaneous death (Art. 43) and open succession per stirpes.

13. Looking Forward

Legislative agenda. Multiple bills seek to repeal Art. 992 and place illegitimate children on absolute parity. As of the 19th Congress, no bill has become law.
Estate‑planning practice. Lawyers increasingly recommend testamentary trusts and lifetime donations to ensure illegitimate children receive more than the compulsory minimum, bypassing Art. 992’s intestate barrier.
Digital records & DNA. Courts now regularly accept DNA profiles; the Public Attorney’s Office offers indigent DNA‑testing vouchers in paternity suits (DOJ Circular 021‑2023).

Conclusion

While the Philippines has progressively expanded the rights of children born outside wedlock, the current framework still imposes two major constraints: the ½‑rule on legitimes and the Art. 992 barrier against legitimate collateral relatives. Knowing when these limits apply—and how legitimation, wills, or trusts can legally circumvent them—is essential for heirs and estate planners alike. Always consider the specific family constellation, gather documentary proof of filiation early, and, where possible, secure professional advice before the estate is opened.