 Under a code sharing agreement, the airline that administers the flight (the one holding the operational permissions, airport slots and planning/controlling the flight and responsible for the ground handling services) is commonly called the "operating carrier", often abbreviated OPE CXR, even though the IATA SSIM term "Administrating carrier" is more precise.The reason for this is that a third carrier may be involved, typically in the case that the airline originally planning to operate the flight needs to hire a subcontractor to operate the flight on their behalf (typically a wet lease, meaning an aircraft is leased with crew and all facilities to fly, commonly due to capacity limitations, technical problems etc.