(1) The Teachers' Retirement System can accept after-tax contributions from a member during a limitation year only if:
(a) the voluntary additional contribution to be made by the member does not exceed the amount determined by the Teachers' Retirement System to be necessary to fund the benefit attributable to such service credit; and
(b) the requirements of Internal Revenue Code (IRC) section 415(b) are met (without regard to any reductions for early retirement age), determined by treating the accrued benefit derived from all such contributions as an annual benefit for purposes of IRC section 415(b); or
(c) the requirements of IRC section 415(c)(1)(A) are met (without regard to the compensation limit), determined by treating all such contributions as annual additions for purposes of IRC section 415(c).
(2) After-tax member contributions cannot be accepted if:
(a) the member is purchasing more than five years of nonqualified service credit; or
(b) any nonqualified service credit is taken into account under this rule before the member has at least five years of participation under the retirement system.