Cal. Civ. Proc. Code § 1345

If any person has erroneously delivered any unclaimed moneys or other unclaimed property to the state or any officer or employee thereof, and the moneys or other property is deposited in the Unclaimed Property Fund or is held by the Controller or Treasurer in the name of any account in that fund pursuant to this title, the moneys or other property delivered in error may be refunded or returned to that person on order of the Controller.