operate and manage RGIA. While doing so, it necessarily interacts/deals with airlines, customers, consumers and various third-party service providers who are willing to provide services or avail services at/of the airport. Any of these can potentially become the service provider or consumer in a downstream market. In the present case, the Informant is the provider of MRO services to the airlines. However, the abuse has specifically been alleged to have happened in the Line Maintenance Services market. Given the parameters under Section 2(t) of the Act, it is observed that the Line Maintenance Services are different from the Base Maintenance Services in terms of characteristics, price and end-use. The duration required to provide these services varies. While Base Maintenance Services, takes place after a long duration of time and are time consuming, the Line Maintenance Services may take place several times in a day in comparatively much lesser time. Additionally, it seems that provisioning of Base Maintenance Services does not require physical presence of the service provider at the airport while in case of Line Maintenance Services, it appears to be necessary. Thus, in terms of labour/infrastructure requirement, characteristics and the frequency for providing these services, Base Maintenance and Line Maintenance Services are different from each other and are hence not substitutable. Hence, the downstream market for the purposes of carrying out the analysis would be ‘ market for the provision of Line Maintenance Services at the RGIA ’.