1) Why this topic is complicated

When a parent is a foreign national, Philippine inheritance questions become a hybrid of:

Philippine family law (to determine who the child is legally, and how filiation is proved), plus
Philippine conflict-of-laws rules (to determine which country’s inheritance law governs the decedent’s estate), plus
Philippine property and procedure rules (because property located in the Philippines is typically settled through Philippine courts/processes even if foreign law governs the shares).

This means an illegitimate child’s right to inherit may depend not only on Philippine rules on illegitimate children, but also on the foreign parent’s national law (and whether that foreign law recognizes inheritance rights for nonmarital children, what shares they get, and whether “forced heirship/legitime” exists at all).

2) Key Philippine legal framework (what you must know first)

A. “Illegitimate child” and what matters for inheritance

In Philippine law, an illegitimate child is generally a child conceived and born outside a valid marriage of the parents (subject to special situations like void/voidable marriages, legitimation, etc.). Illegitimacy affects:

Status (filiation), and
Inheritance share (when Philippine succession law applies).

Even when the parent is foreign, Philippine proceedings often still require the child to prove filiation—i.e., prove that the decedent is their parent—before the child can participate as an heir in settlement proceedings.

B. Who governs inheritance when the decedent is a foreign national

Under Philippine conflict-of-laws rules, the national law of the decedent governs:

Intestate and testamentary succession, including
the order of heirs,
the shares, and
the intrinsic validity of testamentary provisions (e.g., forced heirship/legitime issues), even as to property located in the Philippines.

Practical effect: If the parent died a foreign citizen, the inheritance rights of an illegitimate child (whether they inherit at all, and how much) are generally determined by the decedent’s national law, not automatically by Philippine legitime rules.

C. Philippine law still matters a lot (even if foreign law governs shares)

Even when foreign law determines who gets what, Philippine law typically controls:

Procedure for settling property located in the Philippines (judicial settlement, extrajudicial settlement, probate/allowance of wills),
Evidence rules (including proving foreign law and proving filiation),
Property law constraints (e.g., land ownership restrictions affecting foreign heirs in some cases).

3) Step one in every case: establish filiation (proving the child-parent relationship)

A. Why filiation is the gateway issue

No matter how generous a foreign inheritance law might be, the claimant must still show they are, legally, the decedent’s child. In many estate disputes, the fight is less about “shares” and more about “are you an heir at all?”

B. Common ways filiation of an illegitimate child is proved in Philippine practice

Philippine family law recognizes various modes of proving filiation of illegitimate children, commonly including:

Record of birth / birth certificate showing the parent (especially where the father acknowledges paternity),
Public documents or private handwritten instruments where the parent acknowledges the child,
Open and continuous possession of the status of a child (the parent consistently treated the child as their own, held them out publicly, supported them, etc.),
Judicial actions to establish filiation (which may include modern evidence like DNA testing, depending on circumstances and court rulings).

C. Special difficulties when the parent is foreign

Records may be abroad (civil registry, acknowledgment documents, family court orders).
Names and documentation standards differ across countries.
If the child was not acknowledged during the parent’s life, heirs may contest paternity after death, requiring a more evidence-heavy case.

Practical tip: Inheritance claims become dramatically stronger if paternity/maternity is documented while the parent is alive (e.g., acknowledgment in the birth record, affidavit of acknowledgment, will naming the child, consistent support and recognition).

4) If Philippine succession law applies: the baseline Philippine rule for illegitimate children

This section matters in two big situations:

The decedent is a Filipino citizen at death (not a foreign national), or
The foreign law is not proven in Philippine proceedings (and the court applies a presumption that foreign law is the same as Philippine law).

A. Illegitimate children are compulsory heirs

Under Philippine succession law, illegitimate children are compulsory heirs. That means the law reserves for them a minimum inheritance called a legitime, which cannot be impaired beyond what the law allows.

B. Amount: “half of the legitimate child’s share”

The classic Philippine rule: the legitime of each illegitimate child is one-half (1/2) of the legitime of a legitimate child.

So if a legitimate child is entitled to “1 share,” each illegitimate child is generally entitled to “½ share,” subject to the overall composition of compulsory heirs (legitimate children, surviving spouse, etc.) and whether the succession is testate or intestate.

C. Interaction with legitimate children and surviving spouse

Philippine law’s sharing structure depends on which heirs survive:

legitimate children (or descendants),
illegitimate children,
surviving spouse,
parents/ascendants (if no descendants),
and so on.

Because these combinations can get technical, lawyers usually compute shares based on:

identifying all compulsory heirs,
determining the legitime reserved to each class,
allocating the free portion (if any), and
applying representation rules (if a child predeceased leaving descendants).

5) When the parent is foreign: the governing law is usually foreign law, but you must prove it

A. “Foreign law governs” is not self-executing

In a Philippine court proceeding, foreign law must be alleged and proven like a fact. If it is not properly proven, the court may apply the processual presumption (often phrased as: the foreign law is presumed the same as Philippine law).

Consequence: An illegitimate child might end up receiving a Philippine-style legitime share not because it is correct under foreign law, but because foreign law was not established in court.

B. What “foreign law governs succession” means for illegitimate children

Depending on the foreign parent’s national law:

The child may inherit equally with marital children (many modern jurisdictions have eliminated distinctions).
The child may inherit but with reduced shares or only if formally acknowledged.
The child may be excluded under some legal systems or older rules (sometimes mitigated by later reforms).
Forced heirship/legitime may be strong, limited, or nonexistent (common-law jurisdictions often allow broader freedom of disposition, subject to family provision statutes).

C. Conflict point: foreign law vs Philippine “public policy”

Philippine courts generally apply the decedent’s national law on succession even if it differs from Philippine forced heirship traditions. Still, if the foreign rule is extremely discriminatory, parties sometimes argue public policy or constitutional values—but outcomes are fact- and doctrine-sensitive. As a practical matter, expect the national law rule to control, unless a specific exception is successfully invoked.

6) Property in the Philippines: land and constitutional restrictions (and why heirs still settle locally)

A. Foreign ownership of Philippine land

The Philippine Constitution restricts foreign ownership of private land, with an exception commonly referred to as acquisition by hereditary succession. This matters when:

the decedent owned land in the Philippines, and
the heir (including an illegitimate child) is a foreigner.

Practical effect: Foreign heirs may be able to acquire land through inheritance in situations covered by “hereditary succession,” but the edges can be technical depending on the facts, how the land was acquired, and how the transfer is structured/documented.

B. Condominiums vs land

Foreigners can generally own condominium units (subject to statutory limits on foreign ownership in the condominium corporation). So even where land issues are tricky, condo property inheritance may be more straightforward.

C. Even if foreign law governs shares, Philippine settlement is often necessary

If there are assets in the Philippines (real property, bank accounts, shares of Philippine corporations), heirs typically must undergo Philippine settlement steps to:

transfer titles,
release bank deposits,
register deeds,
and pay estate taxes and comply with documentation requirements.

7) Testate vs intestate: how it plays out for an illegitimate child

A. Intestate succession (no will)

If the foreign parent dies without a will:

Determine the parent’s nationality at death (drives governing law on who inherits and in what shares).
Prove filiation.
Apply the governing law’s intestacy scheme.

Under Philippine law (if applicable), illegitimate children inherit as compulsory heirs and receive shares calibrated relative to legitimate children and the surviving spouse.

Under foreign law (if applicable), the child’s intestate share depends entirely on that foreign intestacy statute and how it treats nonmarital children.

B. Testamentary succession (with a will)

If there is a will, two big questions arise:

1) Is the will valid in form?

Formal validity often depends on rules on wills and conflict-of-laws principles (e.g., place where executed, law of the testator’s nationality, domicile, etc.). In Philippine proceedings involving Philippine assets, the will (or foreign probate) typically must be recognized/allowed through appropriate procedures.

2) Is the will valid “in substance” (shares and forced heirs)?

The intrinsic validity—including whether the will unlawfully disinherits or reduces a protected heir—generally follows the decedent’s national law.

So an illegitimate child’s ability to challenge a will (e.g., “my legitime was impaired”) depends on:

whether the governing national law recognizes a protected share,
whether it recognizes the child as a protected heir,
and what remedies it provides.

C. Disinheritance and omission

Under Philippine law, disinheritance is strictly regulated and must follow specific grounds and formalities. Under foreign law, rules vary widely: some allow broad freedom to exclude children; others require specific grounds or allow “family provision” claims.

8) Legitimation, adoption, and how status can change inheritance rights

A. Legitimation

If the parents were not married at the child’s birth but later marry (and the law allows legitimation under the specific circumstances), the child’s status may change from illegitimate to legitimate—dramatically affecting shares where Philippine law applies, and potentially affecting treatment under foreign law too.

B. Adoption

A legally adopted child typically inherits as a child of the adopter under the adoption law and applicable succession rules. If the foreign parent adopted the child under a valid process recognized in the Philippines (or properly proven/recognized), adoption can be an alternative legal pathway to inheritance rights, especially where biological filiation is disputed.

9) Procedure in the Philippines: how an illegitimate child asserts inheritance rights

A. Typical routes

Judicial settlement of estate (court-supervised; often used when there are disputes, a will, or minor/incapacitated heirs).
Extrajudicial settlement (only when heirs agree and legal conditions are met).
Probate/allowance of a will, including recognition of a foreign will or foreign probate in relation to Philippine assets (often handled through specific procedural steps).

B. What the illegitimate child usually must do

Appear and claim as an heir in the settlement proceeding.
Prove filiation (if contested or not clearly documented).
If foreign law governs: plead and prove foreign succession law relevant to the child’s status and share.
Challenge any settlement that excludes them (e.g., extrajudicial settlement executed without them).

C. Watch-outs: being “left out” of an extrajudicial settlement

A common real-world problem: other heirs execute an extrajudicial settlement and transfer titles without including the illegitimate child. Remedies may include:

challenging the settlement for excluding a rightful heir,
filing actions to annul/impugn the partition as to the excluded share,
seeking reconveyance where property was transferred based on incomplete heirship declarations,
pursuing estate settlement judicially if agreement is impossible.

10) Taxes and documentation: inheritance is not just “who gets what”

Even a clearly entitled heir can be blocked by compliance issues:

Estate tax rules and clearance requirements,
title transfer documentation (registry of deeds requirements),
bank requirements for release of deposits,
authentication of foreign documents (apostille/consularization depending on the document’s origin and applicable rules),
and the need for court orders in contested cases.

11) Common scenarios and how the answer changes

Scenario 1: Foreign parent dies a foreign citizen; child is illegitimate; assets in the Philippines

Governing succession law: foreign parent’s national law.
Threshold requirement: child must prove filiation.
Critical litigation issue: proving foreign law and whether it recognizes the child’s inheritance rights.

Scenario 2: Foreign parent dies but foreign law is not proven in Philippine court

Court may apply processual presumption → Philippine succession rules may be applied by default.
The illegitimate child may benefit (or lose) depending on what the unproven foreign law actually says.

Scenario 3: Parent was once Filipino, later naturalized abroad; property in Philippines includes land

Determine citizenship at death (this is often decisive for which succession law governs).
Land transfer to foreign heirs triggers constitutional/property-law considerations, but inheritance transfers may still be possible under the hereditary succession exception depending on circumstances.

Scenario 4: There is a will that omits the illegitimate child

Child may contest based on the governing national law:
- If forced heirship applies and includes nonmarital children → possible reduction/annulment of dispositions that impair the child’s reserved share.
- If broad testamentary freedom applies → child may have limited or no recourse (unless family provision remedies exist under that law).

12) Practical roadmap (what an illegitimate child should gather and do)

Proof of filiation: birth records, acknowledgments, communications, support evidence, photos, public recognition, any will statements, and possible DNA-related evidence strategies.
Proof of decedent’s nationality at death: passport records, naturalization certificates, etc.
Locate Philippine assets: titles, tax declarations, bank accounts, corporate shareholdings.
Obtain and authenticate foreign documents: death certificate, foreign probate orders, will copies, civil registry documents.
Prepare to prove foreign law in Philippine proceedings if the decedent was foreign at death.
Move quickly if property is being transferred via extrajudicial settlement without inclusion.

13) Bottom-line principles to remember

Filiation first: no proven parent-child relationship, no inheritance right.
If the decedent was a foreign citizen at death, the foreign national law usually governs the child’s inheritance share—even for property in the Philippines.
Foreign law must be proven in Philippine proceedings; otherwise, courts may apply Philippine law by presumption.
Philippine procedure and property rules still shape the actual transfer of Philippine assets.
Land ownership restrictions can affect how inheritance is implemented, especially where heirs are foreigners, but inheritance-based acquisition is often treated differently from ordinary purchase.

This is general legal information in the Philippine context and is not a substitute for advice on a specific case. If you share the parent’s nationality, whether there is a will, and what Philippine assets exist (land/condo/bank/shares), the analysis can be tailored to the most likely governing rules and pressure points.