California Code, Code of Civil Procedure - CCP § 1604

(a) All unclaimed intangible property, together with all interest and other increments accruing thereto, is subject to delivery to this state if the last known address of the owner is in this state. If the last known address of an owner is in this state, any other owner's address which is unknown shall be presumed to be in this state. If the last known addresses of owners are in this state and in one or more other states, the addresses of other owners whose addresses are unknown shall be presumed to be within this state if the federal agency having custody of the unclaimed property initially acquired possession in this state. If the records of the United States do not disclose the address of any owner of unclaimed property, such address shall be presumed to be within this state if the federal agency having custody of such property initially acquired possession in this state. All addresses presumed to be within this state are presumed to be within the County of Sacramento. For the purposes of this chapter, it shall be presumed that the situs of unclaimed intangible property is in this state if the last known or presumed address of the owner is in this state.

(b) All unclaimed tangible property is subject to delivery to this state if the federal agency having custody of the unclaimed property initially acquired possession in this state.