Philippine succession law is codified primarily in Book III of the Civil Code of the Philippines (Republic Act No. 386, as amended), spanning Articles 774 to 1105. These provisions govern both testate and intestate succession and apply to all natural persons domiciled in the Philippines, except Muslims whose inheritance is regulated by the Code of Muslim Personal Laws (Presidential Decree No. 1083). Ancestral property—real or personal property acquired by the decedent through inheritance from his or her ascendants (parents, grandparents, or earlier generations)—forms part of the decedent’s separate or capital estate. Under the Family Code of the Philippines (Executive Order No. 209, as amended), property inherited during marriage is classified as exclusive property of the inheritor and does not form part of the absolute community of property or conjugal partnership of gains (Family Code, Article 92 and Article 109). Upon the owner’s death, this ancestral property is liquidated together with other assets to constitute the net estate available for distribution to heirs.

Succession opens at the moment of death (Civil Code, Article 777). The estate passes immediately to the heirs, subject first to the payment of debts, taxes, and charges. Ancestral property, being part of the separate estate, is fully included in the gross estate for purposes of computing legitimes and shares. The surviving spouse and grandchildren (as descendants) enjoy protected rights as compulsory heirs, which cannot be defeated except by valid disinheritance for causes enumerated in Article 919 of the Civil Code.

Property Classification and Its Impact on Ancestral Property
Before distribution, the surviving spouse’s property regime must be settled. Under the default conjugal partnership of gains or absolute community of property, the community property is liquidated first: the surviving spouse receives one-half outright as his or her conjugal share (Family Code, Article 102). The decedent’s one-half share of the community property, plus all separate property—including ancestral land or houses inherited from parents or grandparents—forms the estate proper. Ancestral property is therefore never automatically owned by the surviving spouse; it is subject to the heirs’ legitime and intestate shares. If the decedent was single or widowed at the time of inheritance, the entire ancestral property enters the estate without prior conjugal division.

Special laws may apply. For indigenous cultural communities and indigenous peoples, Republic Act No. 8371 (Indigenous Peoples’ Rights Act of 1997) recognizes ancestral domains and lands. Transmission follows customary law rather than the Civil Code, provided the domain has been certified. In such cases, surviving spouses and grandchildren may claim rights under tribal customs, which often emphasize collective ownership and priority to direct descendants, but the Civil Code governs non-certified ancestral lands or properties of non-indigenous Filipinos.

Rights of the Surviving Spouse
The surviving spouse is a compulsory heir under Article 887 of the Civil Code. His or her rights are twofold: (1) ownership of one-half of the community or conjugal property, and (2) a legitime from the net estate of the deceased spouse.

When legitimate children or descendants exist, the spouse’s legitime equals the share of one legitimate child (Civil Code, Article 892). The legitimate children collectively receive one-half of the net estate as their legitime (Article 888), divided equally among them. The spouse receives an identical portion. The remaining free portion may be disposed of by will. In intestate succession, the same rule applies: the spouse concurs with the children and receives exactly the same share as one child (Article 996).

If no legitimate children or descendants survive, the spouse receives one-half of the estate, with the other half going to legitimate parents or ascendants (Article 994). If the decedent left no other compulsory heirs, the spouse inherits the entire estate.

Additional protections include:

The right to administer the estate until final settlement (Rule 73, Rules of Court).
The family home—often built on ancestral land—is exempt from partition and execution up to the value allowed by law and may be occupied by the surviving spouse for life or until remarriage, subject to the rights of minor children (Family Code, Article 159).
The spouse enjoys usufruct or use rights over certain portions in specific cases, such as when minor children are left.
Estate tax at a flat 6% rate (Republic Act No. 10963, TRAIN Law) is imposed on the net estate, including ancestral property, and must be paid before transfer of titles.

Rights of Grandchildren
Grandchildren are compulsory heirs as legitimate descendants. They do not inherit directly if their parent (the decedent’s child) is still alive; the parent excludes them. However, grandchildren inherit by right of representation when their parent predeceases the decedent, is incapacitated, or is disinherited (Civil Code, Article 981). Representation occurs only in the direct descending line and is per stirpes: the grandchildren collectively receive the exact share their deceased parent would have received, including both legitime and free portion.

In intestate succession, grandchildren divide their parent’s share equally among themselves. If the decedent left a will that omits or inadequately provides for the grandchildren’s legitime, they may file an action for completion of legitime within the prescriptive period. Grandchildren also participate in collation: any donations or advances received by their parent from the decedent during life are brought back into the estate for equal division (Article 1061).

If all children survive and no representation applies, grandchildren may still receive property through testamentary disposition from the free portion or through inter vivos donations. They hold no automatic right over ancestral property unless representation or a will grants it.

Combined Rights and Division Process
When both the surviving spouse and grandchildren (by representation) exist, the net estate—including ancestral property—is divided as follows:

Legitime of legitimate children (or representing grandchildren) = one-half of net estate, divided per stirpes.
Surviving spouse’s legitime = share equal to one legitimate child’s portion.
Free portion (balance) may go to anyone designated in the will or, in intestacy, augments the shares proportionally.

In intestate succession with representing grandchildren and a surviving spouse, each stirps (branch) receives an equal share, and the spouse receives a share equal to one full child’s portion. Ancestral property is partitioned in kind whenever possible; otherwise, it is sold and the proceeds divided. Co-ownership results until actual partition, and any heir may demand partition at any time (Article 1083).

Extrajudicial settlement of estate is allowed when there is no will, no debts, and all heirs (including spouse and representing grandchildren) are of legal age (Rule 74, Rules of Court). A public instrument and publication are required, followed by transfer of title at the Register of Deeds. If minors are involved or disputes arise, judicial partition or settlement through probate court is mandatory.

Collation ensures fairness: prior donations of ancestral parcels to a child must be accounted for, reducing that branch’s share. The 30-year prescriptive period applies to actions for recovery of real property (ancestral land) from the estate.

Testate vs. Intestate Succession
In testate succession, the decedent may dispose of the free portion but cannot impair legitimes. A surviving spouse or representing grandchildren may petition for the completion of legitime if the will violates their protected shares. Valid disinheritance of a spouse or grandchild requires an express statement and one of the causes in Article 919 (e.g., attempt against life, abandonment). Without such cause, the disinherited heir can demand his or her legitime plus damages.

In intestate succession (no will or invalid will), the rules above apply automatically, giving the surviving spouse and grandchildren equal protection. Ancestral property passes intact to the heirs without testamentary preference.

Special Rules, Taxes, and Protections

Estate tax is 6% of the net estate, inclusive of ancestral property, with deductions for family home, standard deductions, and debts (TRAIN Law). No separate inheritance tax is imposed on heirs.
Transfer of ancestral land requires payment of documentary stamp tax, capital gains tax (if applicable), and registration fees before new titles are issued.
The family home exemption protects the surviving spouse’s right to continue residing on ancestral land used as the family home.
For indigenous ancestral domains, customary law under IPRA may grant the surviving spouse and grandchildren collective rights subject to tribal council approval, superseding Civil Code rules within certified domains.

Potential Disputes and Remedies
Common disputes involve:

Whether a particular parcel qualifies as ancestral (separate property).
Computation of legitime when ancestral property values fluctuate.
Claims of preterition (total omission of a compulsory heir).
Prescription of heirship claims after 30 years.
Conflicts between Civil Code and customary law in indigenous communities.

Remedies include actions for partition, reconveyance, completion of legitime, or annulment of fraudulent transfers. Courts strictly protect legitimes to uphold family solidarity and prevent unjust deprivation of ancestral heritage.

Philippine law thus balances the surviving spouse’s immediate conjugal and legitime rights with the grandchildren’s representational rights, ensuring ancestral property remains within the direct family line while respecting testamentary freedom within legal limits. All transfers must comply with registration laws to perfect title and protect third-party buyers.