Can a co-owner sell the property without the other co-owner’s agreement?

Short answer: Under Maryland law, a co-owner (a tenant in common) can usually transfer or sell only their own ownership share without the other co-owner’s permission. The buyer receives that share, not the entire property. If a sale or transfer was improper, the non-selling co-owner has several remedies: file a partition action, quiet title, seek an accounting or injunction, or pursue fraud or equitable remedies if the sale involved deception.

Detailed answer — what happens and what you can do

1. Understand the type of co-ownership

Begin by confirming how the property is owned. The two common forms are:

Tenants in common: Each owner has a separate, transferable share that they may sell or gift without the co-owner’s consent. The buyer receives only the seller’s share.
Joint tenancy (or tenancy by the entireties for married couples): These forms carry survivorship rights and can restrict unilateral transfers in practice. For married owners holding as tenants by the entireties, one spouse generally cannot convey the property to a third party without the other spouse’s participation.

If the recorded deed shows “tenants in common,” a co-owner can unilaterally convey their share. If the deed shows joint tenancy or tenancy by the entireties, different rules and protections can apply.

2. Effect of a unilateral sale by a co-owner

If a co-owner sells their share, the buyer becomes a co-owner (usually a tenant in common) holding only that fractional interest. The non-selling co-owner keeps their share and their rights (use, possession, and claim to rents or profits proportional to ownership), but the property is now co-owned with a new person.

3. Main legal remedies in Maryland

Depending on the facts, a co-owner who objects to a sale can pursue one or more of these actions:

Partition action (most common): Ask the court to physically divide the property (partition in kind) or order a sale and split the proceeds among owners (partition by sale). Maryland courts routinely hear partition suits when co-owners cannot agree. See Maryland Courts’ self-help resources for civil actions and property disputes: https://www.mdcourts.gov/legalhelp.
Quiet title / cloud on title action: If the sale produced a defective, fraudulent, or improperly recorded deed, you can seek a court order clearing title, removing the improper deed, and confirming your ownership interest.
Injunction or lis pendens: If a sale is pending and you have a strong basis to show it is wrongful (fraud, forged signature, or similar), you may seek a temporary injunction to stop closing or request a lis pendens to put third parties on notice of a claim affecting title.
Accounting and adjustments: A court can require an accounting for rents, profits, taxes, and expenses. If the buyer or selling co-owner received rents or benefits that should be shared, a court can order compensation.
Fraud, constructive trust, or other equitable remedies: If the sale occurred through fraud, forgery, undue influence, or concealment, you may ask a court to impose a constructive trust on the proceeds or otherwise undo the transaction and award damages.

4. Typical court outcomes and practical effects

If the court orders partition by sale, the property will be sold (often at public auction) and net proceeds divided among co-owners by their ownership shares.
If partition in kind is feasible (land can be fairly divided), the court may physically divide the land instead of ordering a sale.
If the sale to a third party was only of one owner’s share, the non-selling owner generally keeps their share; the court will protect that interest unless fraud or other wrongdoing is proven.

5. Time, cost, and evidence considerations

Partition and quiet-title cases take time and can be expensive. A successful result often depends on good records: deeds, the chain of title, settlement statements, proof of forgery or fraud (if alleged), proof of ownership shares, and any communications among co-owners.

6. When the sale may be void or voidable

Examples where the sale can be undone or challenged:

Forgery of a co-owner’s signature on a deed.
False notarization or fraudulent documentation.
Sale procured by undue influence, coercion, or serious deception.
Violation of a recorded restriction, court order, or marital-tenancy protection (for tenancy by entireties).

7. Steps a co-owner should take now

Obtain a copy of the recorded deed and the county land-records entry to confirm exactly what was conveyed and when. You can search county land records online or at the clerk’s office.
Check what was recorded after the sale (a deed, mortgage, or lien). Recording a deed does not always fix defects—those can be challenged in court.
Gather evidence: prior deeds, communications, witnesses, bank records, settlement statements, or any document showing fraud or agreement terms.
Consider filing a partition or quiet-title action if you want the property divided or the title cleared. If you suspect fraud, consider a temporary injunction or lis pendens to protect the property pending litigation.
Consult a Maryland real property attorney quickly if fraud, forgery, or complex transactions are involved. An attorney can explain strategic options, help prepare pleadings, and evaluate possible claims for damages or equitable relief.

Relevant Maryland resources and statutes

Maryland law on property and court procedures is available from statewide government resources. Useful starting points:

Maryland Courts — Legal Help and procedural information: https://www.mdcourts.gov/legalhelp
Maryland General Assembly — access the Maryland Code and search for the Real Property Article: https://mgaleg.maryland.gov

Partition, quiet-title, and equitable remedies in Maryland are governed by case law and statutory provisions found in the Maryland Code and in court rules. For statute text and to search for specific sections that address real property remedies, use the Maryland General Assembly site above.

Helpful hints

Act quickly if you suspect forgery or fraud — early steps (recording a notice, seeking temporary relief) can protect your rights.
Even if a co-owner sold without consent, the buyer generally gets only that owner’s share — your ownership interest does not automatically disappear.
Partition actions can result in sale at auction. Consider negotiation or buyout offers before starting litigation.
If the property is held as tenancy by the entireties (usually for married couples), consult counsel — transfer rules differ from tenants in common.
Keep clear records of payments, repairs, taxes, and rent; courts use those to allocate credits and charges in partition and accounting proceedings.
Title insurance may protect some buyers; check any title policy issued at the sale for coverage or claims procedures.

Disclaimer: This is general information about Maryland property law and is not legal advice. Nothing in this article creates an attorney-client relationship. For advice about your specific situation and to evaluate potential claims (partition, quiet title, injunction, fraud), consult a licensed Maryland attorney.