California Code, Family Code - FAM § 853

(a) A statement in a will of the character of property is not admissible as evidence of a transmutation of the property in a proceeding commenced before the death of the person who made the will.

(b) A waiver of a right to a joint and survivor annuity or survivor's benefits under the federal Retirement Equity Act of 1984 (Public Law 98-397)   1 is not a transmutation of the community property rights of the person executing the waiver.

(c) A written joinder or written consent to a nonprobate transfer of community property on death that satisfies Section 852 is a transmutation and is governed by the law applicable to transmutations and not by Chapter 2 (commencing with Section 5010) of Part 1 of Division 5 of the Probate Code.