Sec. 4.1020. Government Service Buy Back Program. (a) Definitions. For the purpose of this section, the following words and phrases shall have the meaning ascribed to them in this subsection, unless a different meaning is clearly indicated by the context: Buy Back shall mean purchase by a member of retirement credit for periods of eligible service with other governmental entities or purchase by a member of retirement credit for uncompensated maternity leave. Full-time Service shall mean a minimum of six (6) months of uninterrupted service with an eligible governmental entity, excluding part-time service. Governmental Entity shall mean the United States Government, including its territories, any agency of the United States Government, the United States Postal Service and any branch of the United States military service; any State or political subdivision thereof; any local government or special district within any State in the United States, and shall exclude non-governmental agencies supported by government contracts or grants and any prior service with the City of Los Angeles. Government Service Buy Back Program or GSB shall mean the method for the buy back of retirement credit set forth in this section. Prior Plan shall mean a retirement plan of a governmental entity in which the member was a participant during full-time service. Uncompensated Maternity Leave shall mean a leave of absence from City Service taken for maternity reasons without pay, provided that such leave shall be a minimum of one (1) month and a maximum of twelve (12) months with respect to any one pregnancy. (b) Eligibility. A member is eligible to buy back credit for periods of full-time service with other governmental entities and to buy back credit for periods of uncompensated maternity leave. Notwithstanding the foregoing: (1) Members may not buy back credit for periods of service for which they are currently eligible or will become eligible to receive a retirement benefit from a prior plan, provided, however, that to the extent required by federal law, periods of service in the United States military reserve may be purchased even if the Member is eligible to receive a retirement benefit from the prior plan.