The combined merchant fleets compose almost 90% of all the interstellar spacecraft in the Imperium. Each fleet is based in one of the five Segmentae Majoris, and its administrative staff operate from the Segmentum Fortress. Although these fleet bases are huge ports equipped with docks, shipyards and repair facilities, their main function is to administer the fleets operating within their area. Only a small proportion of ships ever travel to the Segmentum Fortress where they are theoretically based.
Each merchant ship serves its fleet under an arrangement called a Merchant Charter. Not all charters are the same - some confer more power and responsibility to the ship's captain than others - but all types take the form of a feudal oath sworn to the fleet authorities on behalf of the Emperor. A captain may not register his vessel with the fleet authorities until this oath has been sworn and a record of it entered at the Segmentum Fortress for that zone and on the Segmentum Fortress on Mars.
Merchant Fleet Ships
- Armed Freighter
- Vagabond Class Merchant Trader
- Universe Class Mass Conveyor
- Carrack Hauler
- Fast Clipper
- Galaxy Class Armed Freighter
- Tarask Class Merchantman
- Goliath Class Forge Tender
- Heavy Transport
- 1: White Dwarf 139 (UK), pg. 17
- 2: White Dwarf 140 (UK), pg. 50
- 3: Rogue Trader: Battlefleet Koronus, pgs. 29-30