Cal. Code Regs. tit. 18 § 13671.3
Where a husband and wife deposit funds in a bank or savings and loan account as joint trustees, revocable by either and payable to either or the survivor, the account shall be treated in the same manner as a joint tenancy account upon the death of the first to die of said joint trustees. For example, assume that funds of A and B, husband and wife, are deposited in a bank or savings and loan account titled "A and B as joint trustees for C." The account is revocable by either A or B, can be drawn on by either and upon the death of either the account s payable to the surviving joint trustee. Upon death of A, the account becomes the property of B with continued right to revoke or withdraw. C has only a contingent interest in the account in the event B does not revoke or withdraw during lifetime. Hence, as between A and B the account is recognized for inheritance tax purposes to have the same effect as a joint tenancy account. If the account is still in existence at the death of B, the payment of the funds to C will be treated as a transfer from B to C.
NOTE: Reference: Section 13671, Revenue and Taxation Code.
Cal. Code Regs. Tit. 18, § 13671.3