A mechanic's lien is a security interest that California law gives to contractors, subcontractors, laborers, material suppliers, and design professionals who have contributed to an improvement of real property but have not been paid. The lien attaches to the property itself and can ultimately be used to force a sale of the property to satisfy the unpaid debt.

Any person or company that provides labor, services, equipment, or materials used in the construction or improvement of California real property can potentially file a mechanic's lien — including general contractors, subcontractors of all tiers, material suppliers, equipment lessors, architects, engineers, and surveyors, provided they have followed all applicable notice requirements.

A California Preliminary Notice (also called a 20-Day Preliminary Notice) is a written notice that subcontractors, suppliers, and other claimants (other than direct contractors) must serve on the owner, general contractor, and lender within 20 days of first providing labor or materials. Failing to serve a proper Preliminary Notice generally bars the claimant from filing a valid mechanic's lien.

For direct contractors, a mechanic's lien must be recorded within 90 days of completion of the work of improvement (or 60 days after a notice of completion or cessation is recorded). For all other claimants (subcontractors, suppliers, etc.), the deadline is 30 days after recording of a notice of completion or cessation, or 90 days after completion if no notice is recorded.

After recording a valid mechanic's lien, the claimant must file a lawsuit to foreclose on the lien within 90 days of recording, or the lien will be automatically released. The lawsuit asks the court to order the property sold and the proceeds applied to the unpaid debt. An attorney should be retained promptly to ensure deadlines are met.

Yes. A property owner can petition a California court to release an invalid or unenforceable mechanic's lien by posting a release bond equal to 125% of the lien amount. The owner can also seek a court order expunging a lien on procedural grounds, such as failure to serve the required Preliminary Notice or missing filing deadlines.

Yes. A recorded mechanic's lien clouds the property's title. Title companies will typically require that the lien be released, bonded over, or resolved before insuring a sale or refinance. This gives lien claimants significant leverage to negotiate payment.

A conditional waiver is effective only upon receipt of payment and is commonly exchanged before a check clears. An unconditional waiver releases lien rights immediately regardless of whether the check is honored. California law provides standard forms for both; using the correct form is critical to preserving or waiving your rights properly.