Ed. Code, § 25015

(a) If a member elects to receive a benefit payable under the Defined Benefit Supplement Program as a joint and survivor annuity, the designation of the beneficiary made pursuant to Section 24300 or 24300.1 shall apply to the benefit payable under this chapter. The annuity beneficiary designation shall not be changed after the date the benefit becomes payable to the member, except as provided in Section 24320, 24321, 24322, 24323, 24324, 25011, 25011.1, 25018, or 25018.1, or Chapter 12 (commencing with Section 22650).

(b) If the member designates one or multiple option beneficiaries within Option 8 pursuant to Section 24300 or the compound option pursuant to Section 24300.1, the percentage of the unmodified allowance attributable to each option beneficiary specified in that designation shall apply to the joint and survivor annuity payable under this chapter. The member shall elect one joint and survivor annuity type and this annuity type shall be applied the same for each beneficiary and each designated percentage of the member only annuity. If any percentage of the allowance was designated to remain unmodified, the member only annuity shall apply for the corresponding percentage of the annuity provided under this chapter. The annuity amount payable to the member during the member’s lifetime shall be modified to be payable over the combined lives of the member and the annuity beneficiary or beneficiaries.

(1) Pursuant to Section 401(a)(9) of the Internal Revenue Code, the member shall not designate the 100-percent beneficiary annuity type under this subdivision if any annuity beneficiary is more than exactly 10 years younger than the member, unless that annuity beneficiary is the member’s spouse or former spouse who has been awarded a community property interest in the member’s benefits under this part.

(2) Pursuant to Section 401(a)(9) of the Internal Revenue Code, the member shall not designate the 75-percent beneficiary annuity type under this subdivision if any annuity beneficiary is more than exactly 19 years younger than the member, unless that annuity beneficiary is the member’s spouse or former spouse who has been awarded a community property interest in the member’s benefits under this part.

(c) (1) If the member predeceases an annuity beneficiary, the annuity beneficiary may designate, on a properly executed form provided by the system, a payee to receive an amount that may be payable in a lump sum pursuant to Section 25023 upon the death of the annuity beneficiary.

(2) Unless otherwise specified in the trust instrument, the trustee or beneficiary of the trust that is an annuity beneficiary is entitled to name a subsequent beneficiary if the trust is valid. If the trust is determined to be invalid or terminates, any election by the trustee pursuant to this paragraph shall be void and the beneficiary shall be entitled to exercise all rights provided to annuity beneficiaries under this part.