Cal. Bus. & Prof. Code § 7030
"Contractors are required by law to be licensed and regulated by the Contractors State License Board which has jurisdiction to investigate complaints against contractors if a complaint regarding a patent act or omission is filed within four years of the date of the alleged violation. A complaint regarding a latent act or omission pertaining to structural defects must be filed within 10 years of the date of the alleged violation. Any questions concerning a contractor may be referred to the Registrar, Contractors State License Board, P.O. Box 26000, Sacramento, CA 95826."
"Information about the Contractors State License Board (CSLB): CSLB is the state consumer protection agency that licenses and regulates construction contractors.
Contact CSLB for information about the licensed contractor you are considering, including information about disclosable complaints, disciplinary actions and civil judgments that are reported to CSLB.
Use only licensed contractors. If you file a complaint against a licensed contractor within the legal deadline (usually four years), CSLB has authority to investigate the complaint. If you use an unlicensed contractor, CSLB may not be able to help you resolve your complaint. Your only remedy may be in civil court, and you may be liable for damages arising out of any injuries to the unlicensed contractor or the unlicensed contractor's employees.
For more information:
Visit CSLB's internet website at www.cslb.ca.gov
Call CSLB at 800-321-CSLB (2752)
Write CSLB at P.O. Box 26000, Sacramento, CA 95826."
Ca. Bus. and Prof'l. Code § 7030