A sale may be annulled or declared void if any of the essential elements of a valid contract are defective. Under the Civil Code, these elements are: consent, object, and cause. Common reasons for questioning a sale include:

• Lack of valid consent — One party was forced, intimidated, or tricked into selling.
• Vice of consent — Error, fraud, or undue influence affected the decision.
• Seller lacked authority — The person who signed the deed had no right to sell (e.g., only one spouse sold conjugal property without the other’s consent).
• Defective title — The seller did not have clean title to the property.
• Non-payment or incomplete payment — The buyer failed to pay as agreed.

There is an important legal distinction:

Voidable Contract (Annulment)

If the contract was valid until challenged (e.g., sale with vice of consent), it is voidable. The injured party must file for annulment within 4 years from the time the defect was discovered.

Void Contract (Declaration of Nullity)

If the contract is void from the beginning (e.g., sale of conjugal property without spousal consent), the action for declaration of nullity does not prescribe. It can be challenged at any time.

Deed of Absolute Sale Was Forged

If the seller’s signature was forged, the deed is void. The true owner can file a case to declare the deed null and void, and to cancel any title that was issued based on the forged deed.

Sale by One Spouse Without Consent

Under the Family Code, the sale of conjugal property requires the consent of both spouses. A sale made by only one spouse without the other’s written consent is voidable.

Sale of Inherited Property Without Settlement

If a property was inherited but the estate was not yet settled, the heirs cannot validly sell it until the estate proceedings are complete and the property is properly titled in their names.