1) The Deed of Absolute Sale (DOAS): what it is and why “heirs” become an issue

A Deed of Absolute Sale is the common Philippine instrument used to document a completed sale of property (most often real property) where ownership is transferred from seller to buyer for a stated consideration. In practice, it is used to (a) prove the parties’ agreement, (b) support tax filings, and (c) serve as a registrable instrument for transfer of title.

When “heirs” enter the picture, it usually means the property is connected to a decedent’s estate or co-ownership among heirs—creating a frequent mismatch between:

who is shown on the title (often the deceased),
who has transmissible rights (the heirs), and
who actually signed the DOAS (sometimes not all heirs).

An addendum is often proposed to “fix” or “complete” the sale documentation—especially to include heirs who were not included or who did not sign earlier.

2) Addendum, amendment, correction, ratification: similar tools, different legal effects

In Philippine conveyancing practice, several instruments can look alike but do different jobs:

A. Addendum / Supplemental Agreement

An addendum is a document that adds to or supplements the original DOAS. It commonly:

adds missing details (IDs, TINs, addresses, marital status);
clarifies payment terms, possession, taxes, utilities;
adds representations/warranties;
and, sometimes, adds additional signatories such as heirs.

Key idea: an addendum can supplement a contract, but it must still comply with the rules on capacity, authority, consent, and registrability—especially if it affects ownership of real property.

B. Deed of Correction / Rectification

Used when the original DOAS contains clerical or descriptive errors (name spellings, technical description, lot number, title number, boundaries, etc.). Registries and tax offices often prefer a Deed of Correction for these issues rather than a broad “addendum.”

C. Deed of Confirmation / Ratification

Used when a person who should have consented (e.g., an omitted heir/co-owner) later confirms and accepts the transaction and/or conveys their share. This is often the cleanest document when the real issue is missing consent.

D. A New Deed of Sale (Re-execution)

Sometimes the best fix is simply to execute a fresh DOAS with all required parties properly included, especially when the original is materially defective, incomplete, or will be hard to register.

3) Why including heirs matters: basic succession and co-ownership rules

A. Ownership and rights upon death

Under Philippine civil law, when a person dies, their rights and obligations not extinguished by death generally pass to their heirs by succession. In real property transactions, this creates two important realities:

Title may still be in the deceased’s name even though heirs have transmissible rights.
Heirs typically become co-owners of the estate properties until partition (unless a will or judicial settlement provides otherwise).

B. Co-ownership and selling without all co-owners

A common problem: one or some heirs sign a DOAS selling the whole property without the others.

As a general principle in co-ownership:

A co-owner may dispose of their ideal/undivided share, but
cannot validly sell the shares of the other co-owners without authority/consent.

Practical consequence: if only some heirs sold, the buyer may have acquired only what those heirs could legally convey (their ideal shares), not necessarily full ownership of the entire property.

This is why “including heirs” is not just a paperwork preference; it is often essential to deliver what the buyer believes they bought: 100% ownership.

4) Common scenarios where an addendum “including heirs” is sought

Scenario 1: Property still titled in the deceased’s name; heirs already sold

Heirs execute a DOAS even though the Transfer Certificate of Title (TCT/CCT) is still in the decedent’s name, intending to later process estate settlement and transfer.

Reality: Registries and tax authorities typically require estate settlement documents and compliance (including estate tax/eCAR) before transfer can be processed.

Scenario 2: Only some heirs signed; one or more heirs were omitted

Later, the parties discover a missing heir—sometimes because of:

incomplete family information,
unknown or later-identified compulsory heirs (including illegitimate children in some cases),
heirs abroad,
or simple oversight.

Scenario 3: One person signed as “attorney-in-fact” without proper SPA

A relative signs “for and in behalf of” heirs without a valid Special Power of Attorney (SPA) or without proper legalization/authentication. An addendum is proposed to attach/confirm authority—or to have heirs sign directly.

Scenario 4: Estate settlement document exists but the DOAS doesn’t match it

For example, an Extrajudicial Settlement lists heirs and shares, but the DOAS:

uses inconsistent names,
omits an heir,
or sells the wrong percentage/share.

Scenario 5: Documentation is complete but registration/tax processing requires additional details

BIR/LGU/RD often requires details that were not included in the original DOAS (TINs, IDs, marital status, exact technical descriptions, etc.). An addendum/correction deed is used to comply.

5) Before choosing an addendum: determine what must legally be accomplished

An “addendum including heirs” may be trying to do one or more of these:

Add missing heirs as sellers so the conveyance covers all shares;
Obtain ratification of the earlier sale from omitted heirs;
Correct descriptions or identities to match title and estate documents;
Support registration (RD) and tax clearances (BIR/LGU);
Allocate obligations (estate tax, capital gains tax, documentary stamp tax, transfer tax, registration fees, etc.);
Confirm payment or provide receipts/acknowledgments.

If the true defect is missing consent/authority, a simple “addendum” that only lists names is usually not enough. The instrument must contain a clear conveyance (or ratification) by the heirs and must be properly executed and notarized.

6) Estate settlement and conveyancing: the backbone of an “heirs” transaction

A. Judicial vs extrajudicial settlement

Judicial settlement involves court proceedings (commonly where there are disputes, minors without proper representation, unclear heirship, debts/creditors issues, etc.).
Extrajudicial settlement is available in specific circumstances (commonly: intestate, no outstanding debts, heirs agree, and legal requirements are met). It is typically done by a public instrument and involves publication requirements.

B. The practical registration reality

Even if heirs are the “real parties in interest,” the Registry of Deeds commonly requires a chain of registrable documents to move the title:

Estate settlement instrument (or court order) to recognize transfer of rights from the decedent to heirs; then
Conveyance to buyer (sale/assignment/confirmation); then
Issuance of new title in buyer’s name.

In practice, many transactions use an Extrajudicial Settlement with Sale (or settlement + sale instruments presented together) to streamline the chain—subject to acceptance by the relevant offices and completeness of requirements.

C. Estate tax and the eCAR bottleneck

Transfer of real property from a decedent’s name typically requires estate tax compliance and issuance of the BIR’s authority to register (commonly referred to as eCAR). Without it, the Registry of Deeds generally will not transfer title.

7) When an addendum is appropriate—and when it is not

A. Addendum is commonly appropriate when:

the original DOAS is valid and complete as a conveyance, and the addendum only adds clarifications (payment schedule, possession date, tax allocation, minor corrections that do not change the substance);
the addendum adds missing documentary details required by notaries/tax offices (IDs, TINs, addresses);
the addendum functions as a supplemental undertaking (e.g., seller commits to produce estate documents by a certain date).

B. Addendum becomes risky or insufficient when:

the defect is missing ownership/consent (omitted heirs/co-owners did not sign);
the original DOAS purports to sell 100% but the signatories could legally convey less;
the property is still in the decedent’s name and there is no workable settlement pathway;
the addendum is being used to retroactively “insert” sellers into a deed that has already been notarized and possibly processed—offices may treat this as a new conveyance for tax/registration purposes;
the addendum changes fundamental terms (consideration, property identity, share allocation) in a way that triggers re-computation and re-filing of taxes and may raise fraud/avoidance concerns.

Often cleaner alternatives (depending on facts):

Deed of Confirmation/Ratification by omitted heirs;
Deed of Sale of Undivided Share by omitted heirs in favor of the buyer;
Deed of Waiver/Renunciation (carefully structured; may be treated as donation or sale depending on consideration);
Re-executed DOAS with all proper parties.

8) Legal capacity, authority, and special situations involving heirs

A. Minors or incapacitated heirs

If an heir is a minor or legally incapacitated, additional safeguards apply. As a rule, transactions affecting their property rights may require proper representation and, in many cases, court authority/approval depending on the nature of the disposition and applicable rules. This is a frequent reason why a “simple addendum” is not enough.

B. Heirs abroad

Heirs outside the Philippines may sign through:

notarization before a Philippine consular officer (consular notarization), or
local notarization with proper legalization/apostille where applicable, plus compliance with Philippine requirements for acceptance.

C. Heirs signing through an attorney-in-fact

If someone signs for heirs, the SPA must generally:

be specific as to the act of selling/conveying real property,
identify the property,
authorize signing and receiving consideration (if applicable),
and be properly notarized and recognized.

D. Surviving spouse and conjugal/community considerations

When property belonged to a married decedent, the surviving spouse may have a legally defined share depending on the property regime and whether the property is conjugal/community or exclusive. Estate settlement must reflect this correctly; otherwise, knowing who must sign becomes complicated.

9) Drafting an addendum “including heirs”: what it should contain (substance, not just names)

To function as a real conveyancing fix, an addendum must be drafted to match the legal objective. If the purpose is to include heirs so the buyer acquires full ownership, the document usually needs clear conveyance language and not merely an “acknowledgment.”

A. Core structural parts

Title and nature “ADDENDUM (or SUPPLEMENT) TO THE DEED OF ABSOLUTE SALE dated ___”
Reference clause Identify the original DOAS by:

date of execution/notarization,
document number/page/book/series (notarial details),
parties,
property identifiers (TCT/CCT number; lot/unit details).

Recitals (whereas clauses) Explain why heirs are being included, e.g.:

the registered owner is deceased;
parties desire to include omitted heirs/co-owners;
heirs confirm their relationship and rights;
parties confirm that the intent has always been to convey the entire property.

Identification of heirs List each heir with:

full name, citizenship, civil status, address;
relationship to decedent;
government ID details;
and, ideally, a reference to supporting documents (death certificate; marriage/birth certificates; extrajudicial settlement; judicial declaration).

Statement of rights/shares State whether heirs are co-owners and, if known, the shares (or that they collectively represent the entire interest). Misstating shares can create later disputes.
Conveyance or ratification clause (the heart of the fix) Depending on strategy, one of the following must be clearly stated:

Option 1: Conveyance by heirs (as additional sellers) The heirs, for and in consideration of the same purchase price (or specified portion), sell, transfer, and convey their shares/rights to the buyer.

Option 2: Ratification/confirmation Heirs confirm and ratify the prior sale and expressly convey any interest they have, so there is no ambiguity that title is being transferred.

Option 3: Sale of undivided shares Each omitted heir sells and transfers their undivided share to the buyer for a stated consideration.

Consideration and receipts Address whether:

the original price covered all shares, and heirs acknowledge receipt (and from whom); or
the buyer pays additional amounts to omitted heirs; or
the consideration is allocated per share.

This is not only contractual; it can affect tax treatment and later claims.

Warranties and representations Common representations to include:

heirs are the lawful heirs (or among them) and have capacity;
no other heirs exist (or disclosure of potential heirs);
no adverse claims, liens, or pending litigation (or full disclosure if there are);
consent is free and voluntary;
documents submitted are genuine.

Undertakings for estate settlement and registration If the title is still in the decedent’s name, include obligations and timelines:

who files estate settlement documents;
who shoulders estate tax and costs;
cooperation commitments (signing forms, appearing, providing IDs/TINs).

Taxes and expenses allocation Typical allocations:

estate tax: often charged to the estate/heirs by agreement, but can be negotiated;
capital gains tax/withholding (depending on asset classification and parties): often seller;
documentary stamp tax: often buyer (by practice, though negotiable);
transfer tax and registration fees: often buyer (by practice, negotiable).

The addendum should reflect the parties’ agreement clearly.

Effectivity and integration State that the addendum is attached to and forms an integral part of the original DOAS; in case of conflict, specify which prevails.
Notarial acknowledgment For real property, notarization is critical for registrability. Ensure the notarization is properly done, with competent evidence of identity and correct details.

B. Annexes typically attached

certified true copy of TCT/CCT or owner’s duplicate details;
tax declaration and latest real property tax receipts;
death certificate of the registered owner;
proof of heirship (marriage/birth certificates; judicial declarations if any);
extrajudicial settlement instrument (or court orders) when applicable;
SPAs (if any), with proper notarization/authentication;
valid IDs, TINs, community tax certificates where required by practice.

10) Notarization and execution details that often decide success or failure

Even a well-drafted addendum can fail in processing if execution formalities are sloppy.

Common execution best practices

Use consistent names matching IDs and civil registry records (watch for middle names, suffixes, accent marks, multiple surnames).
Ensure the property identifiers match the title exactly (TCT/CCT number; lot/unit; technical description).
Make sure every added heir signs on each page as required by notarial practice custom.
For SPAs, ensure the authority is specific to selling/conveying the described property and signing the addendum/related deeds.
Avoid handwritten edits after notarization; if unavoidable, execute a new corrected instrument.

11) Tax and registration implications: the part most people underestimate

When heirs are added after the fact, offices may treat it as:

a continuation of the original sale, or
a new/separate conveyance by the omitted heirs, depending on timing and document structure.

A. Typical taxes and clearances involved (real property)

Estate tax (where the registered owner is deceased and transfer is from the decedent’s name);
Capital gains tax (commonly applied to sale of real property treated as a capital asset) or other applicable income tax/withholding depending on classification;
Documentary stamp tax on the conveyance;
Local transfer tax (LGU);
Registration fees (Registry of Deeds).

Practical warning: If the addendum changes parties or consideration materially, it can trigger re-assessment and new filing requirements. Late filings can trigger surcharges/interest/penalties depending on circumstances.

B. Registration consequences

To affect third parties and to complete the transfer of title, the conveyance must generally be registered. If the addendum is integral to the conveyance (because it supplies missing sellers), it typically must be submitted/recorded in a manner acceptable to the Registry of Deeds.

In many cases, a Registry will be more comfortable recording a separate deed (sale of undivided share or deed of confirmation/ratification) by omitted heirs rather than “editing” the original sale by addendum—especially if the original DOAS has already been processed or annotated.

12) Third-party effects and risk management (why buyers push to include all heirs)

A. Registration and protection

Under the Torrens system, registration is critical for protecting interests against third parties. However, registration does not magically create ownership if the seller had no right to convey a particular share. This is why ensuring that all heirs with rights have validly conveyed or ratified is central.

B. Double sale and adverse transfers

Where not all owners/heirs have signed, the “unsold” share remains vulnerable to:

later sale by the omitted heir to someone else,
partition disputes,
adverse claims,
estate/creditor issues.

A properly executed and registrable instrument covering all shares reduces these risks dramatically.

13) Common pitfalls in “Addendum Including Heirs” documents

Listing heirs without conveyance language Merely naming heirs as “conforming” or “aware” may not transfer their rights.
No proof of heirship / wrong heirs Incorrect heirship assumptions are a major source of future litigation.
Ignoring minor heirs or heirs with special status This can render the intended transfer vulnerable.
Using an SPA that is too general General authority is often rejected or attacked; real property authority must be specific.
Conflicting property descriptions Even small mismatches (lot number, area, CCT vs TCT identifiers) cause processing failure.
Assuming an addendum fixes estate settlement Heirs cannot bypass the estate settlement/tax clearance pathway when the title remains in a decedent’s name.
Under-documenting consideration Omitted heirs may later claim they never agreed to price/payment; clear acknowledgments matter.
Improper notarization Defective notarization can make a document non-registrable and undermine enforceability.

14) Practical document strategy: choosing the best instrument for the situation

Situation A: Omitted heir is cooperative and the original DOAS is not yet fully processed

Common workable approach:

execute an addendum that includes the heir as a seller with explicit conveyance/ratification language,
align it with estate settlement documentation,
then process taxes and registration with the full packet.

Situation B: Original DOAS already registered or title already transferred to buyer

Often cleaner approach:

omitted heirs execute a separate deed (sale of undivided share or confirmation/ratification with conveyance) directly in favor of the current registered owner,
then register that instrument to consolidate ownership.

Situation C: There is uncertainty on heirs (potential undisclosed compulsory heirs)

More cautious approach:

pause “paper fixes,”
establish heirship conclusively (civil registry and, if needed, judicial proceedings),
then execute settlement and conveyance with correct parties.

Situation D: Minor heirs or disputes among heirs

Typically requires a judicially safe route; an addendum is rarely sufficient.

15) Clause checklist (quick reference) for an addendum that truly “includes heirs”

Clear reference to the original DOAS (date, notarial details, title number).
Complete identification of each heir with IDs and relationship to decedent.
Clear statement of heirship basis (and reference to supporting documents).
Clear statement of rights/shares and co-ownership context.
Express conveyance (sell/transfer/convey) of each heir’s share or express ratification plus conveyance.
Consideration allocation and receipt acknowledgments.
Warranties on title/claims/heirship and disclosure of encumbrances.
Undertakings for estate settlement, tax filings, eCAR, and RD compliance.
Allocation of taxes/fees and timeline obligations.
Integration clause linking addendum to the original DOAS.
Proper notarization and execution (including SPAs/overseas formalities where applicable).
Annexes: title documents, death certificate, proof of heirship, settlement instrument, IDs.

16) Bottom line

In Philippine property transactions, “including heirs” is not a cosmetic update—it is usually about curing missing consent and completing the chain of ownership. An addendum can work when it is drafted as a true conveyancing instrument (or a clear ratification with conveyance), executed with proper authority and formalities, and aligned with estate settlement and registration requirements. When the issue is fundamental—uncertain heirship, minors, disputes, or a title already processed—separate, purpose-built instruments (confirmation/ratification or sale of undivided shares, and proper settlement documents) are often the legally sturdier path.