an undertaking (e.g. shippers, consignees, forwarders, etc.) provided it has entered into, or demonstrates an intention to enter into, a contractual or other arrangement with a conference or shipping line for the shipment of goods, or any association of shippers, any undertaking (e.g. shipper, consignee, forwarder, etc) which has entered into ... a contractual arrangement with a "consortium" ... for the shipment of goods...