Here’s a clear, practice-oriented legal guide—Philippine context—on Special Power of Attorney (SPA) vs. Authority to Sell for real property. No web search used.

1) The quick headline

To validly sell land/condo/house through an agent, Philippine civil law requires a Special Power of Attorney (SPA) expressly authorizing the sale of a specifically described immovable and its key terms.
An “Authority to Sell” (ATS)—often used as a listing/marketing authority for brokers—does not, by itself, empower the holder to sign the Deed of Sale or transfer ownership unless it meets the requirements of a true SPA.

Think of it this way: SPA = power to sign and bind owner; ATS = permission to market/find a buyer (unless it is drafted as, and formalized like, an SPA).

2) Legal backbone (Civil Code guideposts)

Agency & special powers. An agent needs a special power for acts of strict ownership—selling real property is one of those acts. The power must be express, in writing, and specific as to the immovable and transaction.
Form & enforceability. Contracts for the sale of real property and authority to sell immovables must be in writing (Statute of Frauds principles). A notarized SPA turns it into a public instrument, gives it presumption of regularity, and allows registry annotation.
Effect on title transfer. The Registry of Deeds (ROD) and BIR routinely require a notarized SPA (and, if executed abroad, apostilled/consularized) before they accept a Deed of Sale signed by an agent.

3) SPA vs. ATS at a glance

Feature	SPA to Sell Immovable	Authority to Sell (listing/marketing)
What it does	Lets agent sign the Deed of Absolute Sale, accept payments/earnest money (if granted), and bind principal	Lets broker/agent advertise, canvass, receive offers; no power to sign sale unless text elevates it to an SPA
Must be in writing?	Yes (and typically notarized)	Yes for clarity; but not sufficient for transfer unless it meets SPA requirements
Typical contents	Owner/principal & attorney-in-fact; technical description of property; minimum price/terms; authority to sign deeds & tax docs; bank dealings; receipt/issuance of OR; power to appoint sub-agents (if any); validity/revocation	Owner & broker/agent; exclusivity, listing price, commission rate, term; marketing channels; no authority to sign sale (unless explicitly converted into SPA and notarized)
Who uses it	Attorney-in-fact (could be a relative, lawyer, trusted person)	Licensed real-estate broker (RES practitioners), or owner’s sales agent
Registry/BIR acceptance	Accepted for title transfer if properly executed	Not accepted for title transfer by itself

You can combine them: a document titled “Authority to Sell” can also function as an SPA if it expressly grants the power to sell/sign and is properly notarized (and apostilled if signed abroad). But mere “authority to sell/market” language is not enough.

4) What a valid SPA to sell should say (practical checklist)

Identity & capacity

Full names, marital status, citizenship, addresses of principal(s) and attorney-in-fact; if married property, spousal consent (see §8).

Property

Exact description (TCT/OCT number; lot/block; area; condo unit/parking details; location). Attach copy of title and tax declaration.

Authority granted (state clearly; don’t assume)

To sell the property for not less than ₱[amount] (or to negotiate and accept offers subject to minimum price/terms).
To sign: Deed of Absolute Sale / Contract to Sell / Deed of Assignment; acknowledgment receipts, OR for sums received.
To receive: earnest money/down payment (state ceiling) and balance (with bank details/escrow instructions).
To sign BIR/ROD/LGU papers: Capital Gains Tax/creditable withholding tax forms, DST, eCAR processing, transfer tax, realty tax clearances, association/condo certs.
To secure releases: bank mortgage cancellation, loan payoff, SPA for specific bank dealings if property is mortgaged.
To appoint sub-agents (only if you want this).
To deliver possession upon completion (optional).

Boundaries

No self-dealing unless expressly allowed (e.g., agent may purchase); state whether allowed and price rules.
State no right to assign the SPA unless permitted.

Term & revocation

Effectivity (date/period; “until revoked” if preferred) and revocation clause.
Survival clause: agency ends on death or incapacity of principal; you may allow substitution if named.

Formalities

Notarization in the Philippines (acknowledgment).
If executed abroad: apostille (or consular authentication where apostille not available) then notarization recognition locally.
Documentary stamp tax on SPA is commonly paid (as required for certain instruments).

5) What an Authority to Sell (listing) should cover (if not intended to be an SPA)

Exclusivity (exclusive right to sell vs. non-exclusive).
Term (start/end), price, net-of or plus commissions.
Commission (rate, when earned—upon acceptance of offer vs completion; forfeiture if seller backs out without cause).
Marketing: permitted channels, signage, open houses, data privacy consents.
Access for viewings; keys; safety.
No power to bind the owner to a sale; offers require owner’s acceptance in writing.
If you want the agent to collect earnest money, say so (cap amount and escrow instructions).

RES compliance. The Philippine RESA Law requires licensed real estate service practitioners for brokerage practice; an ATS doesn’t “license” someone to broker if they aren’t duly licensed. An SPA also doesn’t waive licensing rules for brokerage; it only authorizes representation of the owner.

6) Married owners, co-owners, estates, corporations—special rules

Married property

If the property is conjugal/absolute community, both spouses generally must consent to sell. If one spouse executes the SPA, the other spouse must also sign (as co-principal or to give spousal consent); otherwise, the sale risks voidability.

Co-ownership

All co-owners must authorize the sale of the entire property—either by joining the SPA or issuing separate SPAs to the same attorney-in-fact. A single co-owner may authorize sale of his/her undivided share only.

Estate property

Title in the decedent’s name: generally, you need a court authority (judicial settlement) or an Extrajudicial Settlement (EJS) + SPA by all heirs (or by the administrator if judicial). Buyers and registries look for eCAR (estate tax) before transfer.

Corporations

Need Board Resolution authorizing the sale and naming the corporate signatory or agent; if delegating via SPA, attach the Board/Secretary’s Certificate. Check articles/by-laws for realty dispositions.

Guardians/trustees

Court approval is often required to sell minors’ or incompetent persons’ property. An SPA alone is insufficient; attach the court order.

7) Common traps (and how to avoid them)

Generic ATS used to sign sale. If the document doesn’t explicitly grant power to sell and sign and is not notarized, it will not pass BIR/ROD.
No minimum price/terms. Ambiguity invites disputes and accusations of breach of fiduciary duty.
Self-dealing by the agent. An agent cannot sell to themself or to their spouse/affiliates unless the SPA clearly permits it on stated terms.
Expired or revoked SPA. Registry may reject; buyer risks a void/voidable deed. Always check effectivity and ask for Affidavit of Non-Revocation at closing.
Foreign execution without apostille/consularization. The SPA becomes unusable locally.
Missing spousal/co-owner consent. Expect title transfer blockage and possible litigation.
Agent exceeds authority (e.g., accepts lower price, releases title early)—principal can repudiate and third parties may be left to claim against the agent.

8) Revocation, death, and notice to third parties

Revocation is generally free for the principal, but give written notice to the agent and publish/notify counterparties who relied on the SPA (buyers, brokers, bank, registry).
For real property, consider annotating the SPA (and later the Revocation) on the title to put the world on notice.
Agency terminates by death or civil interdiction of the principal (unless nature of the act or law provides otherwise). Transactions after death, without notice, can be contested. In practice, buyers ask for an Affidavit of Non-Revocation & Life at signing.

9) Roadmap: selling through an agent (owner’s perspective)

Decide: SPA (signing authority) vs. ATS (marketing only).
Draft the SPA with all §4 elements; have all owners/spouses sign & notarize (apostille if abroad).
Due diligence folder for the agent: title, tax dec, tax clearances, IDs, photos, association/condo certs, mortgage statements.
Broker engagement (if any): sign ATS (exclusive or not), define commission & earnest-money handling.
Negotiation: agent gathers offers; principal approves price/terms (or agent acts within SPA limits).
Signing: agent signs Deed of Absolute Sale/Contract to Sell; collects funds per SPA; issues ORs if required.
Taxes & transfer: file CGT/CWT, DST, secure eCAR, pay transfer tax, then ROD for new TCT/CCT.
Turnover: possession, HOA/condo clearances, utilities transfer.

10) Buyer’s protection when dealing with an agent

Ask for the SPA (original or certified copy), check notary acknowledgment, dates, property description, price floor, and agent’s ID.
If principal is married, check spousal consent. If co-owned, ensure all principals gave power.
If SPA was signed abroad, require apostille/consularization and ID of signatory.
Get an Affidavit of Non-Revocation & Life dated close to signing.
Pay only as allowed in SPA; large sums via manager’s check/escrow; get official receipts.
Consider title annotation of the SPA (and later the sale) to avoid double sales.

11) Sample clauses & short templates (adapt to your facts)

A) Special Power of Attorney to Sell (short-form skeleton)

SPECIAL POWER OF ATTORNEY I/We, [Name(s) of Owner(s)], [civil status], [citizenship], of [address] (“Principal/s”), appoint [Name of Attorney-in-Fact], [details], of [address], as my/our Attorney-in-Fact, to:

SELL the property covered by [OCT/TCT No. ___], located at [full description; lot/block/area/unit], for not less than ₱[amount], under cash or bank-financed terms customary in the market;

SIGN any Deed of Absolute Sale/Contract to Sell, acknowledgments/receipts, and all BIR/ROD/LGU papers (CGT/CWT/DST/eCAR/transfer tax/realty tax/condo-HOA certifications), and submit/receive documents and checks;

RECEIVE earnest money/down payment up to ₱[cap] into [bank details/escrow], and deliver possession upon full payment;

[Optional] SELL to self/relative/entity (allowed/not allowed) subject to price floor and arm’s-length terms;

[Optional] Appoint sub-agents. This SPA is effective from [date] to [date/until revoked] and revocable by written notice. Executed this [date] at [City], Philippines. (Signatures of principal/s) ACKNOWLEDGMENT [notarial block]

B) Authority to Sell (Listing) – Non-SPA

AUTHORITY TO SELL (LISTING) Owner [Name] authorizes [Licensed Broker/PRC No.] to market property [description] for ₱[price] from [start] to [end], exclusive/non-exclusive. Commission: [__%], earned upon [acceptance/closing]. Broker may receive earnest money up to ₱[cap] [to be deposited in escrow/broker’s trust account]. Broker has no authority to sign a deed of sale or transfer title; all offers subject to Owner’s written acceptance. (Signatures; PRC/ID details; date)

Note: If you want the broker to sign on your behalf, do not rely on this form. Issue an SPA.

12) If things go wrong: ratification, rescission, and disputes

Agent exceeded authority (sold below minimum price; altered terms): principal can disown the sale; buyer may claim against the agent. A principal may ratify the unauthorized act, curing defects from the start.
Double sale (owner sells to two buyers): rules on first registrant in good faith apply; buyers should register immediately.
Breach by agent: principals can sue for damages, accounting, and cancel agency; criminal liability can arise for estafa (abuse of confidence).
Unlicensed brokerage: can affect commission entitlement and expose parties to administrative liability; it does not automatically void a properly executed sale signed by a duly authorized attorney-in-fact.

13) Practical FAQs

Q: Can I sell property using only an ATS my cousin signed? A: Not for signing the deed. Issue a notarized SPA with the property details and price.

Q: I’m overseas. What do I need? A: Sign the SPA before a competent notary abroad and obtain an apostille (or consular authentication where applicable). Send the original to the Philippines.

Q: Can my agent also receive the full purchase price? A: Only if the SPA says so. For safety, use escrow or have payment direct to owner.

Q: My spouse is abroad and co-owner. Can I sign alone with an SPA from them? A: Yes—if the spouse issues a proper SPA (apostilled/consularized) expressly authorizing you to sell.

Q: Can an SPA be irrevocable? A: Agencies coupled with an interest (e.g., given as security) can be made irrevocable for the agreed period. Ordinary sale SPAs are revocable anytime, subject to liability for abuse.

14) Bottom line

If you want someone to bind you in a sale of real property, issue a clear, notarized SPA that names the property and terms.
Use an Authority to Sell when you only intend marketing + commission; don’t expect it to transfer title.
For married/co-owned/estate/corporate properties, secure the right consents and board/court papers.
Buyers should verify the SPA’s validity, scope, spousal/co-owner consent, and non-revocation before paying.

This guide is general information, not legal advice. For live transactions (mortgaged titles, adverse annotations, estate/co-owner issues, foreign execution), consult counsel and align your SPA/ATS with current registry and tax-processing practices.