Co-ownership is common in the Philippines—siblings inherit a house, friends buy land together, or spouses separate but keep a property undivided. This article gathers the core rules under the Civil Code (primarily Arts. 484–501, with related remedies and special statutes) and translates them into practical guidance you can actually use.

1) What is a co-ownership?

A co-ownership exists when ownership of the same thing or right belongs to two or more persons, each holding an ideal or undivided share (a percentage, not a specific corner of the land or room in the house).

Typical ways it arises

Succession (heirs take undivided estate property).
Purchase or donation to multiple persons.
Accretion or commingling (e.g., merging of movables, floods depositing soil).
By law or court order (e.g., partition suspended).

Nature of the interest

Each co-owner has full ownership of their ideal share and co-possession of the whole.
Presumption of equal shares if the title is silent; this can be rebutted by proof (e.g., who paid more).

2) Core rights of every co-owner

A. Right to use and enjoy the thing

You may use the whole property in line with its intended purpose, without injuring the thing or prejudicing the equal right of the others.
Use must be proportionate to your share and compatible with co-use by others.

B. Right to fruits and income

Civil fruits (rent), natural fruits (harvest), and industrial fruits are shared in proportion to shares.
A co-owner who alone collected rent or produce owes accounting to the others.

C. Right to dispose of your ideal share

You may sell, donate, exchange, or mortgage your undivided share without consent of the others.
The buyer steps into your shoes as a new co-owner (but see the legal redemption rule below).
You cannot unilaterally sell or encumber a specific physical portion (e.g., “the western half”) until partition.

D. Right to manage and to be heard

Acts of administration (e.g., hiring a caretaker, collecting rent, paying taxes) may be decided by the majority of interests (measured by shares, not headcount).
If no majority, or the majority’s decision is seriously prejudicial, any co-owner may ask the court to decide.

E. Right to prevent alterations

Alterations or acts of strict ownership that change the thing’s identity or purpose (e.g., converting a house into a nightclub, building a new floor) require unanimity. Without unanimous consent, the alteration may be stopped or undone.

F. Right to demand partition at any time

No one is obliged to remain in co-ownership. Any co-owner may demand partition anytime.
Exceptions (when partition may be barred temporarily):
- The co-owners agree in writing to keep it undivided for up to 10 years (renewable).
- A donor or testator validly prohibits partition for up to 20 years.
- Law prohibits partition (e.g., when partition would render the thing unserviceable for its intended use).
Partition is in kind if practicable; if indivisible or seriously impaired by division, the court may order allocation to one with indemnity or a public sale, then divide the proceeds.

G. Right to sue

Any co-owner may file ejectment or other actions to recover the whole from a stranger; recovery benefits all (subject to accounting).

H. Right of legal redemption (pre-emption/retraction)

If a co-owner of an undivided immovable sells their share to a non-co-owner, the remaining co-owners have a legal right to redeem the share.
Priority: Co-owners outrank adjoining owners under other redemption rules.
Period: A short window (counted from written notice of the sale) to exercise redemption in proportion to shares; if multiple co-owners redeem, they share the purchase pro rata.
Tip: Always give written notice of the sale to start the redemption period running.

3) Core duties of every co-owner

A. Contribute to expenses and taxes

Co-owners must share in necessary expenses for preservation, repairs, and taxes in proportion to their shares.
A co-owner who advanced these amounts may collect reimbursement with interest from the others.

B. Respect co-possession and avoid acts of exclusion

Possession by one is deemed on behalf of all. You cannot oust co-owners or appropriate the whole.
Usucapion against co-owners is not available unless the possessor performs a clear, unequivocal repudiation of the co-ownership, notifies the others (or the repudiation is notorious), and prescription runs only from that point.

C. Observe decisions and limits on alterations

Necessary repairs: Any co-owner may undertake urgent necessary repairs after due notice to the others and charge the common fund.
Useful or luxury improvements: Generally need majority (useful) or unanimous (alterations/strict ownership) consent. If made without proper consent, the improver may be limited to removal if possible without damage or recovery of the lesser of cost or increase in value, depending on good/bad faith and circumstances.
Administration: Follow majority-of-interests decisions; absent a majority, seek judicial direction.

D. Keep fair accounts

Anyone collecting rents, using the property exclusively, or handling funds owes regular accounting and must turn over net amounts due to co-owners.

4) Partition: how it works

A. By agreement (extrajudicial)

Co-owners survey and divide the property in kind according to shares.
If physical division is impracticable (e.g., a small urban lot with a single house), they may sell and divide proceeds or adjudicate to one who pays indemnity to the others.
Titles, tax declarations, and condo subdivision documents are updated to reflect the partition.

B. Judicial partition

Filed when consent is lacking, boundaries are contested, or indivisibility is at issue.
Court may appoint commissioners/surveyors, receive valuations, and decree in-kind division, adjudication with indemnity, or public sale if needed.

C. Effects of partition

Co-ownership ends. Each former co-owner becomes exclusive owner of their allotted portion.
Co-owners warrant to each other title and possession of the parts allotted (up to the value received), akin to reciprocal warranty in partition.

5) Repairs, improvements, and reimbursements—who pays?

Scenario	Consent Needed	Who Pays	Takeaway
Urgent necessary repairs (prevent loss/deterioration)	Prior notice (if practicable); unilateral action allowed if urgent	All, in proportion to shares	Document urgency, notify co-owners, keep receipts
Non-urgent necessary repairs	Majority of interests	All	Use a written resolution; budget & apportion
Useful improvements (increase value/utility)	Majority of interests (administration)	Those who approved; dissenters may opt out unless decision validly binds all	Align with intended use to avoid challenge
Alterations (change identity/purpose)	Unanimous	If done without unanimity, removal or limited reimbursement rules apply	When in doubt, treat as alteration and secure unanimity

Note: Local building rules and permits still apply.

6) Income, exclusive use, and accounting

Exclusive use by one does not automatically entitle others to rent, but if it excludes them or generates income, expect accounting and sharing.
If one co-owner occupies the whole without excluding others and no rent is charged, courts look at fairness, consent, and local practice in deciding compensation.
Keep a common ledger: rentals collected, expenses paid, and balances by share.

7) Dealings with third parties

Leases: A lease granted by the majority binds the co-ownership as an act of administration (watch the lease term; very long leases may be treated as acts of strict ownership).
Mortgages: A mortgage over one co-owner’s ideal share is valid only up to that share; the mortgagee cannot foreclose a specific corner until partition.
Sales: A sale by one of the entire property is valid only as to their share; the buyer becomes a co-owner with the rest.
Torrens title: Due diligence and proper registration remain essential to protect buyers and lenders.

8) Taxes and fees

Real property tax (RPT) and assessments are borne pro rata.
Capital gains tax/creditable withholding, documentary stamp tax, and registration fees apply to sales of undivided shares or to transfers on partition (often treated as non-taxable conveyances of own share, but check current BIR rules on partitions, exchanges, and basis allocations).
Keep individual TINs, a working bank account (if collecting rent), and ORs for clean accounting.

9) Ending or pausing a co-ownership

Agreement not to partition: Up to 10 years (renewable).
Testamentary/donative prohibition: Up to 20 years.
Consolidation: One buys out the rest (mind the legal redemption if a non-co-owner is involved).
Partition (contractual or judicial).
Conversion to a different regime: E.g., forming a partnership or corporation to hold title (changes governance, liability, and taxes).

10) Special contexts

Condominiums (R.A. 4726): Unit ownership is exclusive; common areas are held in co-ownership by unit owners in proportion to appurtenant interests. By-laws and the condominium corporation’s rules overlay the Civil Code.
Common walls and fences (party walls): Special rules apply to construction, openings, and cost-sharing.
Spouses and family property: Don’t confuse conjugal/ACP regimes with co-ownership; similar sharing ideas but different codes and consequences.

11) Common pitfalls (and how to avoid them)

Silent titles → Clarify percentages in a side agreement; attach to the title file.
No paper trail → Keep written resolutions, notices of repairs, receipts, and annual accounting.
Improvements without consent → Treat gray areas as alterations; seek unanimity or at least majority with clear minutes.
Selling to outsiders without notice → You risk legal redemption biting later; always serve written notice.
Exclusive occupation with no accounting → Expect disputes; set use schedules or pay occupancy rent by agreement.
Assuming prescription against co-owners** → No; you need a clear repudiation plus notice and time.

12) Practical toolkit

A. Co-owners’ agreement (one-page checklist)

Parties and percentage shares.
Purpose and permitted uses.
Administrator (if any) and decision rules (majority by interests).
Repairs & improvements workflow (notice, bids, approvals).
Bank account and accounting cycle (quarterly).
Renting rules (minimum rate, term caps, broker).
Insurance and RPT responsibilities.
No-partition period (if any; max 10 years) and dispute venue.
Right of first refusal among co-owners before selling to outsiders (separate from statutory redemption).

B. Notices you’ll likely need

Notice of urgent repair (brief description, cost cap, target date).
Call for majority decision (agenda, quorum by shares).
Written notice of sale to start the redemption clock.
Annual accounting (income, expenses, balances by share).

C. Evidence to keep handy

Title, tax dec, survey plan, IDs of co-owners.
Receipts, leases, bank statements.
Resolutions, consents, and service of notices.

13) Quick FAQs

Can one co-owner bar another from entering? Generally no. Each has co-possession. Exclusion invites suits and damages.

Can I build a second floor on our undivided house? Treat as an alteration → unanimous consent. Without it, you risk removal or only limited reimbursement.

We can’t split the lot fairly. Now what? Seek adjudication with indemnity to one co-owner (who pays the others), or a court-ordered sale with division of proceeds.

I bought a sibling’s share; do the others get a say? They can’t block a share transfer, but other co-owners may exercise legal redemption if you are an outsider (or if your buyer is).

How do we stop constant fights? Adopt a written co-owners’ agreement, appoint an administrator, and keep regular accounting. Most disputes are paper problems.

14) Bottom line

Think of co-ownership as shared sovereignty over one thing: broad freedom to use and dispose of your share, balanced by duties to preserve the whole and respect equal rights.
The law favors exit (partition), majority administration, unanimity for alterations, pro-rata burdens, pro-rata benefits, and transparency via notice and accounting.
If stakes are high (e.g., impending sale, redevelopment, or exclusion), get tailored legal advice and formalize your arrangement before problems harden into lawsuits.