Short answer

If you own an undivided interest in real property in California (commonly as a tenant in common after inheritance), you may file a civil lawsuit called a partition action in superior court to ask the court to divide the property physically (partition in kind) or, if division is impractical, order a sale and divide the proceeds. The procedure, practical steps, and likely outcomes are governed by California’s partition statutes and local court rules.

Detailed answer — how a partition action works in California

1. Who can bring a partition action?
Any person with an estate or interest in the real property may seek partition. This typically includes heirs who inherited a fractional share (often as tenants in common). The statutory framework for partition actions begins at California Code of Civil Procedure section 872.010: see the statute here: CCP § 872.010.

2. Before you file — practical steps to prepare

• Confirm ownership. Get a copy of the recorded deed, probate documents (if any), or title report showing your interest and co-owners’ names.
• Determine how you hold title. An inherited interest commonly results in tenancy in common, which is partitionable. Joint tenancy may require severing the joint tenancy if that is an issue.
• Attempt negotiation. Courts prefer parties try to agree on division or sale terms. A written offer or mediation can save time and costs.
• Collect evidence about the property: legal description, parcel number, mortgages or liens, current use, and improvements.

3. Filing the partition complaint
If negotiation fails, you file a complaint for partition in the county superior court where the property is located. The complaint should: identify the property by legal description; name all known co-owners and interested parties (lienholders, mortgagees, tenants); state the type and extent of each person’s interest; and ask the court for partition in kind or for sale. After filing you must serve the complaint and summons on all interested parties.

4. Court procedures — what usually happens next

• Service and response. All co-owners and interested lienholders must be served and have the opportunity to respond.
• Pretrial and discovery. Parties exchange information on value, liens, and use of the property; the court may refer the case to mediation or settlement conferences.
• Appointment of referee or commissioner. California partition law permits the court to appoint a referee or commissioner to evaluate, map, or divide the land; the referee prepares a report and proposed plan.
• Partition in kind vs. partition by sale. The court prefers physical division (in kind) when it is feasible without undue prejudice to owners. If physical division is impractical or inequitable (e.g., single-family parcel that cannot be fairly divided), the court will order sale and apportion the proceeds.
• Sale procedure. When a sale is ordered, the court will set terms—often a public auction or private sale under court supervision—and ensure payment of liens, costs, taxes, and a fair distribution to co-owners according to their interests.

5. Costs, liens, and credits
Liens and mortgages are typically paid from sale proceeds before owners receive net distributions. The court also accounts for necessary expenses (property taxes, repairs, foreclosure of liens). Costs of partition (referee fees, appraisal, sale costs) are usually charged against the estate and apportioned among owners. Attorney fees are not automatically awarded to a prevailing party unless a contract, statute, or equitable ground supports fees.

6. Timeline and complexity
A partition action can take several months to a few years depending on complexity, number of parties, title issues, and whether the property can be divided. Complex title disputes, unresolved probate matters, or numerous lienholders increase time and cost.

7. Interaction with probate
If the property is still titled in a decedent’s name or is part of an open probate estate, you may need to address the probate administration first or name the personal representative as a party. Consult an attorney about concurrent probate and partition issues.

8. Where to file
File the partition complaint in the California Superior Court for the county where the real property is located. Local court rules may set additional filing, format, or fee requirements.

Key statute: The partition statutes are found in the California Code of Civil Procedure starting at section 872.010. See: CCP § 872.010.

Example (hypothetical facts)

Suppose you inherited a one-third undivided interest in a single-family parcel after a parent’s death. Two siblings own the other shares. The siblings cannot agree whether to sell or keep the house. You try mediation and offer to buy their shares, but no agreement is reached. You file a partition complaint in the county superior court, name the two siblings and any mortgagee, request partition in kind or, if not feasible, a sale. The court appoints a referee, determines the house cannot be fairly divided into three equal lots, orders a court-supervised sale, pays off the mortgage, sale costs and property taxes, then divides the net proceeds according to each owner’s share.

Helpful hints

• Get a title report early. It shows co-owners, liens, and potential claimants.
• Consider mediation before filing. Judges routinely encourage settlement and it can avoid the cost of litigation.
• Gather financial records: mortgage statements, tax bills, insurance, and maintenance expenses—these affect net distribution and credits.
• Think about tax consequences. A sale may trigger capital gains taxes; consult a tax advisor.
• Keep records of improvements and payments. You may be entitled to credits for payments you made that benefited the property.
• If title issues or adverse claimants exist, consider hiring an attorney to prepare and prosecute the complaint and handle service and sale procedures.
• Be realistic about cost vs. value. Partition litigation and sale costs can be substantial; compare expected net proceeds to the cost of litigation.