The shipper is the owner of the cargo of a ship or a part of it.
The shipper can be the importer (the goods arrive on the territory) or the exporter (the goods leave the territory) according to the International commercial terms.
Sources : multiples sources internet, ouvrages spécialises, témoignages (Pratic-Export, fiches Pôle-emploi, Wikipédia, Onisep, CNRTL, Umep à la Page…)