California Code, Code of Civil Procedure - CCP § 1575

(a) If the State Controller believes that a person in another state holds property subject to escheat under this chapter and the courts of this state cannot obtain jurisdiction over that person, the Attorney General of this state may request an officer of the other state to bring an action in the name of this state to enforce the provisions of this chapter against such person.

(b) This state shall pay all reasonable costs incurred by the other state in any action brought under the authority of this section. The State Controller may agree to pay to any state bringing such an action a reward not to exceed fifteen percent of the value, after deducting reasonable costs, of any property recovered for this state as a direct or indirect result of such action. Any costs or rewards paid pursuant to this section shall be paid from the Abandoned Property Account in the Unclaimed Property Fund and shall not be deducted from the amount that is subject to be claimed by the owner in accordance with this chapter.