As per Section 1(3) of the POG Act, the POG Act is applicable to:
(a) Every factory, mine, oilfield, plantation, port, and railway company.
(b) Every shop or establishment within the meaning of any law currently in force in relation to shops and establishments in a State, where 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 regard.
The contractor or the contracting company is an establishment within the meaning of the law, without any doubt in my mind. Therefore, the contractor is liable to pay Gratuity to his employees who complete 5 years or more of continuous service with him. Such employees may work for a single PE or multiple, and it is solely the duty and liability of the contractor to provide Gratuity to his employees.