(1)    Payment to 2 or more persons as joint beneficiaries shall be equal unless the participant, employee or annuitant has designated otherwise in the written designation of beneficiary on file with the department.

   (2)   A beneficiary of a deceased participant, annuitant, alternate payee, beneficiary, or employee may waive absolutely and without right of reconsideration or recovery all or part of any benefit payable under this chapter. The beneficiary shall then be determined as if the waiving beneficiary had died prior to the decedent except that if the person was a beneficiary under group 2 under s. 40.02 (8) (a) 2., payment shall be made as if at least one child had survived the participant, alternate payee, beneficiary, employee, or annuitant. Unless the department receives the beneficiary’s written request to cancel the waiver before the date on which it would otherwise become effective, the waiver shall be effective 30 days after it is received by the department or the date specified in the waiver, if earlier. The waiver may be cancelled by the beneficiary in writing before the effective date. A waiver received after the effective date on which a beneficiary has commenced a monthly annuity under s. 40.73 (2) or (3) shall apply to monthly payments payable after the effective date of the waiver. Payment shall be subject to the restrictions specified in s. 40.73 (2) (b).

   (4)   If a participant, employee or annuitant fully terminates all coverage and closes all accounts to which a written beneficiary designation applies, the designation does not apply if the individual again becomes a participant, employee or annuitant.

   (5)   A designation of a testamentary trust as beneficiary shall satisfy the requirement of s. 40.02 (8) (a) 1. that a person or trust be specifically named in a written designation of beneficiary whether the will establishing the trust is written before or after the designation of beneficiary is received by the department. If, however, a designation specified the date or otherwise identified a specific will, the designation shall not apply if the will is not the last will and testament of the participant, employee or annuitant.

   (6)   Any potential primary beneficiary under s. 40.02 (8) who cannot be located by reasonable efforts within 12 months after the later of the date of death of the participant or the date on which the department determines the person, trust, or estate initially became a potential primary beneficiary may be treated as a beneficiary that predeceased the participant and all other potential beneficiaries.

   (7)   A trust that does not exist on the date of the participant’s death or an estate not opened or reopened within 12 months after the department determines the estate initially became a potential primary beneficiary under s. 40.02 (8) may be treated as a beneficiary that predeceased the participant and all other potential beneficiaries.