Cal. Veh. Code § 9869
The department shall transmit information from each initial application and each transfer application or renewal application to the county assessor in the county of residence of the owner of the vessel and to the county assessor in the county in which the vessel is principally kept if other than the county of residence of the owner, if such other county is known to the department. If an application shows that the owner of the vessel has changed his residence from one county to another county or shows that there has been a change in the county in which the vessel is principally kept, the department shall transmit information of the change to the assessor of the county in which the owner of the vessel formerly resided or to the assessor of the county in which the vessel formerly was principally kept. After the department receives a notice pursuant to Section 9864, the department shall transmit information of the destruction or abandonment to the assessor of the county in which the owner of the vessel resides and to the assessor of the county in which the vessel is or was principally kept, if other than the county of residence of the owner, if such other county was known to the department.
Ca. Veh. Code § 9869