CA Prob Code Section 5011

Notwithstanding any other provision of this part, the rights of the parties in a nonprobate transfer of community property on death are subject to all of the following:

(a)

The terms of the instrument under which the nonprobate transfer is made.

(b)

A contrary state statute specifically applicable to the instrument under which the nonprobate transfer is made.

(c)

A written expression of intent of a party in the provision for transfer of the property or in a written consent to the provision.