Section 1(3) in The Payment of Gratuity Act, 1972
(3) It shall apply to:
(a) every factory, mine, oilfield, plantation, port, and railway company;
(b) every shop or establishment within the meaning of any law for the time being in force in relation to shops and establishments in a State, in which ten or more persons are employed, or were employed, on any day of the preceding twelve months;
(c) such other establishments or class of establishments, in which ten or more employees are employed, or were employed, on any day of the preceding twelve months, as the Central Government may, by notification, specify in this behalf.
(It has nothing to do with your previous services). You are doing fresh services in private concerns, and therefore the applicability of gratuity is only subject to the conditions as prescribed in the Payment of Gratuity Act.