1) Core Concepts You Must Understand First

A. What happens to property upon death

In Philippine law, a deceased person’s property, rights, and obligations (not extinguished by death) form the estate. Succession opens at death, and the estate is transmitted to the heirs from that moment, subject to settlement of debts and the administration/partition process.

B. Co-ownership among heirs before partition

Before the estate is partitioned, heirs generally hold the estate property in co-ownership. Each heir’s right is typically an ideal or undivided share in the whole, not ownership of any specific room, corner, or metes-and-bounds portion.

Key consequence: No heir can validly claim to own (and thus sell) a specific physical portion of land or a specific property item as “mine alone” before partition, unless that property has already been validly adjudicated/assigned to them.

C. “Inheritance” vs “title” vs “possession”

Inheritance rights: arise at death (heirs become co-owners of the estate property, subject to settlement).
Title/registration: land titles may still be in the decedent’s name; registration does not create the inheritance, but it affects third-party dealings and proof.
Possession: one heir may possess/use the property; possession does not necessarily equal exclusive ownership.

2) What a Co-Heir Can (and Cannot) Sell Before Partition

A. What a co-heir can sell

A co-owner (including a co-heir) may sell their undivided ideal share in the co-owned property, even without the consent of the other co-owners. This is a sale of a quota (e.g., “my 1/5 share”), not a sale of the entire property or a specific portion.

Effect: the buyer steps into the seller-heir’s shoes as a co-owner (subject to legal limitations and the rights of other co-owners, including redemption in proper cases).

B. What a co-heir cannot validly sell (without authority)

A co-heir generally cannot validly sell:

The entire property (as if they were the sole owner), or
A determinate physical portion (specific boundaries) of the property, without the consent/authority of the others or without a prior partition/adjudication giving that portion to the seller.

Effect: As to the shares of the other heirs, such a sale is ineffective/unenforceable. The transaction may still be effective only to the extent of the seller’s own share (depending on the form and circumstances), but it cannot prejudice the non-consenting heirs.

C. Sale by a “self-appointed” representative

If one heir acts as if they are the administrator/executor or “authorized representative” without proper authority (court appointment in judicial settlement or written authority from co-heirs in extrajudicial arrangements), acts of disposition are vulnerable to challenge.

3) Typical Real-World Scenarios and Their Legal Treatment

Scenario 1: Co-heir sells “the whole land” to a buyer

General rule: valid only as to the seller’s ideal share; void/ineffective as to the shares of the non-consenting heirs. Remedy focus: recovery/recognition of your share, annulment/ineffectiveness as to your share, partition, and damages where warranted.

Scenario 2: Co-heir sells a specific portion (e.g., 300 sqm “at the back”)

Before partition, selling a definite portion is generally not binding on other heirs. The buyer may at best acquire whatever rights the seller eventually gets in partition, but cannot force the other heirs to yield that portion if it was never allocated to the seller.

Scenario 3: Co-heir forges signatures or fabricates an SPA/Deed of Extrajudicial Settlement

This triggers civil remedies (nullity, reconveyance, damages), and may also expose parties to criminal liability (forgery/falsification, estafa in proper cases), and administrative issues for notaries.

Scenario 4: Buyer claims to be an “innocent purchaser for value”

In registered land, buyer protections can be strong if the seller appears on the title as owner and there are no glaring defects. But in inheritance cases, titles are often still in the decedent’s name or irregularly transferred through questionable instruments. Whether “innocent purchaser” protection applies depends heavily on what the title showed, what instruments were registered, and what red flags existed.

4) Your Menu of Remedies (Civil, Procedural, and Practical)

Remedy A: Demand recognition of co-ownership and stop interference

When used: immediately upon discovery, especially if the buyer is taking possession, fencing, leasing, or excluding you.

Common steps:

Send a formal demand/notice to the seller-heir and buyer:
- assert your status as heir/co-owner,
- state that no consent was given,
- demand cessation of acts that exclude you,
- demand accounting for fruits/income if any,
- propose settlement/partition.

This establishes good faith on your side and creates a paper trail helpful for damages and attorney’s fees.

Remedy B: File an action for Partition (with ancillary relief)

Partition is often the most durable endgame because it converts undivided shares into specific allocations (or forces a sale and division of proceeds if partition in kind is impracticable).

What you can ask for alongside partition:

Accounting of rents, fruits, profits, or proceeds received by the selling heir and/or buyer (to the extent they enjoyed benefits belonging to the co-ownership).
Damages if bad faith is shown.
Appointment of a commissioner to partition, survey, and report.
If the property cannot be physically divided: judicial sale and division of proceeds.

Why partition matters: it clarifies what portion belongs to whom and helps unwind or correctly align any transfer the co-heir attempted.

Remedy C: Action to declare the sale ineffective/void as to your share and to recover your rights

Depending on the facts and what is on record, pleadings commonly include:

Declaration of nullity (if the deed is void—e.g., forged signatures, no consent where required by law in the instrument, simulated transaction, etc.).
Annulment (if voidable factors exist).
Reconveyance (if a title was transferred and you seek to reconvey the portion that should belong to you).
Cancellation of title / annotation corrections (if the registry entries stem from void instruments).
Quieting of title (if there is a cloud created by the unlawful sale).

Practical note: The “best” cause of action depends on what exactly was signed/registered and whether the land is titled, untitled, or covered by tax declarations only.

Remedy D: Redemption rights (where applicable)

Philippine co-ownership rules provide legal redemption in certain co-owner sales to strangers, with strict timelines and conditions in many situations. If the sale was only of an undivided share to a third person, other co-owners may have a statutory right to redeem that share by reimbursing the buyer.

When this matters most:

The co-heir sold “my share” to a stranger, and you prefer to keep the property within the family rather than litigate ownership issues.

Cautions:

Redemption is time-sensitive and fact-sensitive (notice issues, who is a “stranger,” what was actually sold, and when you learned of it).
If the deed purports to sell the entire property, courts may treat the transaction differently; you may still argue it was effectively only a share-sale as to the seller’s interest, but strategy varies.

Remedy E: Injunction (temporary restraining order / preliminary injunction)

When used: you need to stop:

construction,
fencing,
eviction/exclusion,
cutting trees, extracting minerals,
leasing to third parties,
selling again to another buyer, while the main case (partition/nullity/reconveyance) is pending.

You typically must show:

a clear and unmistakable right needing protection,
urgent necessity to prevent serious damage,
no adequate remedy at law for the immediate harm.

Remedy F: Lis pendens annotation

If you file a case affecting title/possession of real property, you can seek annotation of lis pendens on the title (for titled land). This warns prospective buyers that the property is under litigation, discouraging further transfers and protecting your position against later transferees.

Remedy G: Accounting and recovery of fruits/proceeds

A co-owner who benefits from the property (or its sale proceeds attributable to the co-owned interest) may be required to account to the other co-owners.

This can include:

rental income,
agricultural produce,
lease payments,
sale proceeds corresponding to your share,
damages for exclusionary acts in bad faith.

Remedy H: Damages and attorney’s fees (bad faith-based)

You may claim damages when the seller-heir (and sometimes the buyer) acted in bad faith, such as:

knowingly selling more than their share,
misrepresenting sole ownership,
forging documents,
excluding co-heirs by force or intimidation,
concealing the sale and refusing to account.

Attorney’s fees are not automatic; they usually require statutory or equitable grounds and must be justified.

Remedy I: Criminal remedies (when there is fraud, forgery, or deception)

Civil cases resolve ownership and recovery. But where facts show criminal conduct, criminal complaints may be considered, commonly involving:

Falsification/forgery (fake signatures, spurious notarization),
Estafa (defrauding co-heirs or the buyer through deceit, depending on the structure of the scheme),
Other related offenses depending on conduct.

Strategic note: Criminal proceedings do not automatically restore property; they can, however, pressure settlement and address fraudulent behavior. They must be used carefully and grounded on evidence.

5) Extrajudicial Settlement Pitfalls That Often Enable Unauthorized Sales

Many inheritance sales happen after someone prepares an Extrajudicial Settlement (EJS) (sometimes with a deed of sale attached), then registers it.

Red flags:

Some heirs are omitted or “waived” without understanding.
Signatures of absent heirs are forged.
An SPA is presented but not actually issued.
A notary notarizes without personal appearance or proper IDs.
The deed is backdated.

Legal impact: If the EJS or the authority documents are void (e.g., forged), the resulting transfer and title annotations are vulnerable to cancellation/reconveyance.

6) Defenses You Will Face, and How They’re Usually Met

Defense 1: “I’m an heir, I can sell.”

Response: You can sell your undivided share, not the shares of others, and not a specific portion before partition without authority.

Defense 2: “You waived your rights / you signed.”

Response: Challenge the authenticity (forensic signature comparison), validity (lack of consent, vitiated consent), compliance (notarization defects), and capacity/authority issues.

Defense 3: “Buyer is an innocent purchaser.”

Response: Attack the basis for good faith:

What did the title show?
Was the title still in the decedent’s name?
Were there obvious irregularities in the chain of title?
Were all heirs properly represented in registered instruments?
Were there suspicious circumstances that required further inquiry?

Defense 4: “Prescription / laches.”

Response: Depends on the remedy and whether the deed is void or voidable, whether you were excluded, whether you had notice, and what acts occurred. Time issues are highly fact-specific; courts consider when the cause of action accrued and whether delay was unreasonable and prejudicial.

7) Evidence Checklist (What Usually Wins or Loses These Cases)

Essential documents

Death certificate of the decedent.
Proof of heirship:
- birth certificates, marriage certificates, recognition/legitimation documents, etc.
Title (TCT/OCT) or tax declaration, survey plans, property documents.
Certified true copies of:
- deed of sale,
- EJS,
- SPAs,
- notarial register entries (where obtainable),
- registry annotations.
Proof of lack of consent:
- your absence from the deed,
- no SPA,
- proof you were abroad/elsewhere at signing.
Proof of bad faith and damages:
- messages, admissions, demand letters,
- receipts of rent collection,
- construction photos, barangay blotter, police reports,
- affidavits of neighbors, tenants.

For forgery issues

Specimen signatures,
IDs showing signature style,
Travel records,
Notary-related records.

8) Choosing the Right Case: Common Procedural Pathways

A. If the property is titled and a new title was issued to the buyer

Often involves:

Reconveyance / cancellation of title (or partial reconveyance),
Declaration of nullity of deed (if void),
Injunction,
Lis pendens,
Partition (either combined or separate, depending on strategy and court practice).

B. If the title is still in the decedent’s name and buyer just took possession

Often involves:

Action to protect co-ownership rights,
Partition and accounting,
Injunction,
If a deed exists: declaration of ineffectiveness/nullity as against your share.

C. If the transaction was only a sale of “share”

Then:

Evaluate legal redemption promptly,
Or proceed with partition while treating buyer as substituted co-owner (if you choose not to redeem).

D. If the property is being leased/earning income

Always consider:

Accounting,
Deposit/escrow of rents under court supervision (where appropriate),
Immediate injunctive relief to prevent dissipation.

9) Settlement Options That Preserve Family Value

Litigation can be slow and expensive. Common settlement structures:

Buy-out: remaining heirs buy the buyer’s acquired share (or vice versa).
Rescission by mutual agreement: buyer returns rights for refund plus reasonable costs.
Partition agreement: heirs agree on allocations; buyer gets the seller’s allocated portion (only after proper partition).
Sale of whole property with division: everyone sells together to one buyer at better price; proceeds divided.

Settlements should be documented carefully, with tax and registration compliance, and with clear releases.

10) Tax, Registration, and Compliance Consequences (Often Overlooked)

Unauthorized sales frequently cause:

Wrongful or premature payment computations,
Estate tax and transfer obligations mishandled,
Penalties/interest,
Registration complications when instruments are later declared void.

From a remedies standpoint:

Improper tax filings do not automatically validate ownership, but they can complicate unwinding.
Courts may order restoration of parties to their prior positions, with reimbursements depending on good/bad faith.

11) Practical Strategy: What To Do Immediately Upon Discovery

Secure certified true copies of title and all registered instruments from the Registry of Deeds (and tax records from Assessor’s Office if untitled).
Document possession and acts on the property (photos, videos, witnesses).
Send a demand letter to seller and buyer; demand accounting and cessation.
If there is ongoing construction or threatened exclusion: file for injunction and annotate lis pendens once a case is filed.
Decide whether to prioritize:
- Redemption (if a share was sold), or
- Partition + nullity/reconveyance, especially if the deed overreaches or is forged.
Preserve evidence of forgery/fraud; consider a forensic route early.

12) Common Outcomes You Can Expect

Buyer remains co-owner only to the extent of the seller’s valid share (if it was effectively a share-sale and buyer acted in good faith).
Sale is set aside as against non-consenting heirs’ shares; title/annotations may be corrected.
Partition is ordered, allocating specific portions; any valid buyer interest attaches only to what the seller was entitled to.
Accounting and damages may be awarded if bad faith and exclusion are proven.
If fraud/forgery is established, civil nullity plus potential criminal accountability may follow.

13) Key Takeaways

Before partition, heirs are usually co-owners with ideal shares.
A co-heir may dispose of only their undivided share, not the whole property or a specific portion belonging to everyone.
Remedies typically combine partition, injunction, lis pendens, nullity/ineffectiveness or reconveyance, accounting, and damages—plus redemption where applicable.
The best remedy depends on what was actually sold, what was registered, the state of the title, and whether there was fraud or forgery.