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The Multiple Operating Authority (MOA) feature allows an organization to segregate and track HOS between various Carriers, as well as, Fuel and Mileage among various Authorities under those carriers.Click here for a background on FMCSA Registrations as this is the structure applied even if you only operate intrastate.
It is important to first understand that one or more Operating Authority belong to a Single Carrier, this image illustrates this relationship: 
Detail regarding an FMCSA Registrations can be here. This is the structure applied even if you only operate intrastate.
When a Driver logs onto an ELD they will be presented with a list of Operating Authorities either from the Vehicles assigned Terminal or a Custom Group which both the Vehicle and Driver have been assigned. The Carrier which that Operating Authority belongs to will be automatically selected.
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