Here’s a full, practice-oriented legal article—Philippine context—on the co-owner’s right of legal redemption after a judicial partition. No web browsing used. I’ll explain the Civil Code framework, what “judicial partition” actually does to a co-ownership, when legal redemption is (and is not) available, deadlines, price/tender mechanics, and messy edge cases you’re likely to see in practice.

Co-Owner’s Right of Redemption After Judicial Partition (Philippines)

Snapshot (the big rules)

Legal redemption among co-owners (Civil Code) lets a co-owner buy the share that another co-owner sold to a stranger, so the co-ownership stays “in the family” and strangers are kept out.
Judicial partition generally terminates the co-ownership. Once the property is partitioned and the decision is final (and lots or aliquot portions are adjudicated), there is no more co-ownership to protect—so the co-owner’s legal redemption right ends.
Legal redemption does not apply to judicial or execution sales (e.g., a court-ordered public auction to implement partition of an indivisible thing). It is designed for voluntary sales by a co-owner, not court sales.
If a sale happens before partition becomes final (or where there’s still co-ownership), redemption may be invoked—but only if strict notice and deadline rules are met.

The legal scaffolding (Civil Code, distilled)

1) Co-ownership & partition

A co-ownership exists when the same property is owned by two or more persons pro-indiviso (undivided shares).
Partition (by agreement or by court) converts ideal shares into exclusive, determinate portions (or, if the thing is indivisible without loss, the court may order a sale and divide proceeds).
Effect of partition once final: co-ownership ends. Each adjudicatee becomes exclusive owner of his/her allotted portion.

2) Legal redemption among co-owners (core idea)

If a co-owner sells his undivided share to a third person (a stranger) while the co-ownership still exists, the other co-owners may redeem (buy that share and step into the buyer’s shoes).
Purpose: minimize co-ownership and exclude outsiders from an intimate ownership relation.

3) Notice & periods (highly technical but crucial)

Redemption must be exercised within 30 days from written notice of the sale given by the vendor or the buyer.
Written notice is the trigger. Without it, the 30-day clock does not start to run. (Recording in the Registry, rumors, or “actual knowledge” do not substitute for the written notice contemplated by the Code.)
One co-owner’s failure to act timely does not stop another co-owner from redeeming within his/her own 30-day window.

4) What transactions qualify

Sales or other onerous alienations (e.g., dación en pago) of the undivided share before the co-ownership ends.
Not covered: donations, swaps that aren’t truly onerous, judicial/execution sales, or sales after partition when co-ownership has already been extinguished.

After a judicial partition: do co-owners still have redemption rights?

A. Partition by adjudication of lots (typical case)

What happens: The court approves a subdivision/lotting plan and awards specific lots to named co-owners.
Effect: When the judgment becomes final and executory (and often titles are re-issued), the co-ownership ceases. Consequence: A subsequent sale by A of Lot 1 (A’s adjudicated lot) is not a sale of an undivided share. It’s a sale by an exclusive owner. → No co-owner’s redemption lies, because Article on co-owners’ redemption protects only ongoing co-ownerships and sales of undivided shares.

B. Partition by sale (indivisible thing sold and proceeds divided)

What happens: The court orders a public sale of the entire property; proceeds are divided among co-owners.
Effect: There’s no voluntary sale by a co-owner to a stranger; it’s a judicial sale to implement partition. → No co-owner’s redemption against the auction buyer; the co-ownership ends upon sale/proceeds distribution.

C. Before partition becomes final (sale during the pendency)

If, while the case is pending and before final partition, Co-owner A voluntarily sells his undivided share to Buyer B (a stranger):
- Other co-owners may redeem (subject to 30-day written notice rule).
- The case proceeds with Buyer B substituted for A (or joined) regarding A’s former undivided share—unless a co-owner redeems within the period and steps in.

Mechanics of exercising legal redemption (when it still exists)

Check that co-ownership still exists. If a final partition judgment already adjudicated specific lots, stop—redemption among co-owners is no longer available.
Confirm it was a covered sale. Must be a voluntary, onerous sale of an undivided share to a stranger (not to another co-owner).
Demand and mark the 30-day period. Upon written notice (from buyer or seller), calendar 30 days. If no written notice has been given, formally demand written notice to start the clock.
Tender the price correctly. Redemption requires paying the same price paid by the buyer plus legitimate expenses (e.g., taxes, registration fees) the buyer incurred for the sale.
- If the buyer refuses, make consignation (deposit in court) to avoid being time-barred.
Document everything. Written notice received, the date received, demand to redeem, tender, buyer’s response/refusal, and consignation receipts.

Multiple co-owners want to redeem? They must all be allowed to exercise the right in proportion to their shares; if some refuse, those willing can proceed for their proportions.

Typical arguments and how they fare

“We can redeem even after partition because we were former co-owners.” ✗ No. After final partition, there’s no longer a sale of an undivided share; legal redemption among co-owners doesn’t apply.
“The auction buyer is a stranger; we can redeem.” ✗ No. Judicial/execution sales are outside the co-owner’s legal redemption rule (it targets voluntary stranger entry).
“We learned about the sale from the Registry; the 30 days lapsed.” ✗ Usually no. The Code contemplates written notice by the seller or buyer; mere registration or grapevine knowledge generally does not start the 30-day clock.
“The price was shockingly low; we can redeem at that price.” ✓ Yes, if the other requisites exist. Redemption price is the price actually paid (plus allowable expenses). If the price was simulated or in bad faith, that factual issue can be litigated.
“The buyer is the spouse/relative of a co-owner—still a ‘stranger’?” ✓ Likely yes. Unless that relative is himself/herself a co-owner, the transferee is a stranger for redemption purposes.

Intersections with heirship and adjacent-land redemption

Co-heirs (succession). Separate Civil Code rules give co-heirs a right to redeem hereditary rights sold to strangers within one month from written notice. That’s distinct from co-owners’ redemption and often arises before partition of the estate.
Adjacent lots (rural/urban pre-emption/redemption). These neighbor rights are different animals with their own conditions and deadlines. They do not revive co-owner redemption after partition.

Litigation & remedies playbook

If you’re asserting no redemption (post-partition seller/buyer)

Show finality of partition (decision, entry of judgment, implementation; new titles if issued).
Show nature of sale (judicial sale vs. voluntary) and timelines.
Move to dismiss any redemption claim for lack of cause of action (no co-ownership at time of sale; or sale was judicial).

If you’re asserting redemption (pre-partition)

Prove co-ownership status on the sale date.
Prove sale to a stranger and written-notice receipt date (to establish your 30-day window).
Make timely tender/consignation of the correct price plus expenses.
Sue for conveyance (specific performance) if buyer resists after proper tender; record a lis pendens if appropriate.

Evidence checklist

Partition docket and final judgment; sheriff’s reports; approved subdivision plan; new TCTs (if any).
Deed of sale (price, date, parties), proof of written notice and the date received.
Tender letter, proof of funds and consignation.
Proof buyer is a stranger (not a co-owner).
If claiming sham or simulated price, corroborating facts (consider valuation reports, taxes paid).

Practical pitfalls to avoid

Banking on “actual knowledge.” Without written notice, your 30-day period likely hasn’t started—but don’t sit on your rights; promptly demand the notice in writing and be ready to tender.
Tendering late or the wrong amount. If you’re redeeming, put up the exact price + allowable expenses; if the buyer stonewalls, consign fast.
Confusing co-heir vs. co-owner rules. The succession rule for co-heirs is not the same as the co-owner rule; the triggers and timing differ.
Assuming redemption survives partition. It doesn’t. Once the co-ownership ends by final partition or by judicial sale, the co-owner redemption right is gone.

Worked mini-scenarios

Sale before partition is final. A (co-owner) sells his undivided 1/3 share to X (stranger) while the partition case is pending. X (or A) serves B and C written notice on June 1. → B and/or C have until June 31 (30 days) to redeem by tendering the price + expenses; if refused, consign and sue for conveyance.
Judicial sale to implement partition. Court declares the land indivisible and orders a public auction. X, a non-co-owner, wins. → No co-owner redemption lies against X (it’s a judicial sale). Co-ownership ends; co-owners take their cash shares.
Partition by lots, then sale. Final judgment awards Lot A to Co-owner 1 and Lot B to Co-owner 2. Co-owner 1 later sells Lot A to X. → No co-owner redemption; sale was by an exclusive owner of a determinate lot after co-ownership ended.

Bottom line

The co-owner’s right of legal redemption is a pre-partition remedy aimed at keeping strangers out of an ongoing co-ownership after a voluntary sale of an undivided share.
A judicial partition (by adjudicating lots or by judicial sale and division of proceeds) extinguishes the co-ownership. Once that happens, legal redemption among co-owners no longer applies.
If you’re still pre-partition, redemption can be powerful—but only if you receive/give written notice, act within 30 days, and tender/consign the exact price plus expenses.
Post-partition disputes should focus on title defects, fraud, or execution issues, not on the co-owner redemption rule, which has run its course.