(a)     Interest of members in system. At no time prior to the satisfaction of all liabilities under the system with respect to retirees and members and their spouses or beneficiaries, shall any part of the corpus or income of the fund be used for or diverted to any purpose other than for their exclusive benefit.

(b)     No reduction of accrued benefits. No amendment or ordinance shall be adopted by the city council of the City of Melbourne which shall have the effect of reducing the then vested accrued benefits of members or a member's beneficiaries.

(c)     Qualification of system. It is intended that the system will constitute a qualified pension plan under the applicable provisions of the code, as now in effect or hereafter amended. Any modification or amendment of the system may be made retroactively, if necessary or appropriate, to qualify or maintain the system as a plan meeting the requirements of the applicable provisions of the code as now in effect or hereafter amended, or any other applicable provisions of the U.S. federal tax laws, as now in effect or hereafter amended or adopted, and the regulations issued thereunder.

(d)     Use of forfeitures. Forfeitures arising from terminations of service of members shall serve only to reduce future city contributions.