Cal. Gov't Code § 21500

(a) Whenever a person entitled to payment of a member’s accumulated contributions or any other benefit fails to claim the payment or cannot be located or a warrant in payment is canceled pursuant to Section 17070, the amount owed from the retirement fund shall be administered in accordance with subdivision (c).
(b) Whenever the amount of a benefit payable by this system cannot be determined because the recipient cannot be identified or information necessary to determination of the benefit to be paid cannot be ascertained, the accumulated contributions of the member on whose account the benefit is payable shall be administered in accordance with subdivision (c).
(c) Notwithstanding any provision of law to the contrary, the amounts described in subdivisions (a) and (b) shall be held, or if a warrant has been drawn the warrant shall be redeposited in the retirement fund and held for the claimant without further accumulation of interest, and the redeposit shall not operate to reinstate the membership of the person with respect to whose membership the refund or benefit was payable in this system. If the proceeds are not claimed within four years after the date of redeposit, they shall revert to and become a part of the reserve established pursuant to Section 20174. Transfer to this reserve shall be made as of the June 30th next following the expiration of the four-year period.
The board may at any time after transfer of proceeds to the described reserve upon receipt of proper information satisfactory to it, return the proceeds so held in reserve to the credit of the claimant, to be administered in the manner provided under this system.
(d) For lump-sum death benefits administered in accordance with subdivision (c), where this system has made a diligent effort to identify or locate the person entitled to payment and that person cannot be found, payment may be made to the next entitled beneficiary or beneficiaries, upon receipt of valid claims, if two years have passed since the date of death. Payment made by this system in good faith and in reliance on those claims, notwithstanding that it may fail to discover a person otherwise entitled to share in the benefits, shall constitute a complete discharge and release of this system for further liability for the benefits.