Maryland Code, State Personnel and Pensions § 23-215

(1) is separated from employment for more than 4 years;

(2) is separated from employment, and rehired into a position that requires enrollment in a part of the Employees' Pension System or the Teachers' Pension System that is subject to a different rate of member contributions and benefit accrual;

(3) withdraws the member's accumulated contributions;

(4) becomes a retiree; or

(5) dies.