In general
The term “permissive service credit” means service credit—
(i)#
recognized by the governmental plan for purposes of calculating a participant’s benefit under the plan,
(ii)#
which such participant has not received under such governmental plan, and
(iii)#
which such participant may receive only by making a voluntary additional contribution, in an amount determined under such governmental plan, which does not exceed the amount necessary to fund the benefit attributable to such service credit.
Such term may include service credit for periods for which there is no performance of service, and, notwithstanding clause (ii), may include service credited in order to provide an increased benefit for service credit which a participant is receiving under the plan.