Question: Cancall Communications, Inc., a distributor of prepaid wireless telephone services, acquired airtime on Omnipoint Corp.'s network that it then resold to its customers. In the prepaid wireless telecommunications industry, each consumer must use a telephone handset that is specifically programmed to access a specific network. The service providers supply Subscriber Identification Module Cards (SIM Cards) to each of their customers. The SIM cards contain specific information about each consumer and enable that consumer to access the network. Omnipoint refused to sell Cancall SIM cards alone, but instead required that Cancall's customers purchase new handsets, which were manufactured by three handset manufacturers (the Equipment Manufacturers) and supplied to Omnipoint for use with its network. While direct Omnipoint customers could purchase the handsets from Omnipoint for $49, Omnipoint charged Cancall $189 for the same handsets. The Equipment Manufacturers refused to sell the handsets directly to Cancall. Cancall has alleged that the Equipment Manufacturers have violated the Robinson-Patman Act. Have they? Why, or why not?