Merchant Marine

Merchant Marine or Merchant Navy, commercial shipping fleet of a nation, including both cargo and passenger ships. In the shipping industry, merchant vessels are normally grouped according to the country where they are registered, whose maritime regulations they follow, and whose flags they fly. This structure parallels the organization of merchant shipping companies.

The size and significance of a merchant marine is measured by its total gross tonnage, the space with the hull and enclosed decks of all ships in the merchant marine. By these measures, Liberia and Panama have the largest merchant marines in the world, reflecting the lenient and economical ship registration rules which encourage companies based in many countries to register ships there and fly their flags as flags of convenience. Greece has the next largest merchant fleet; other nations with large merchant marines include the United States, Great Britain, Japan, Russia, China, Cyprus, and Norway.

Merchant marines traditionally form part of a nation's military resources, are legally obliged to serve their flag in war, and are often encouraged by subsidies and other government inducements for strategic reasons. However, such terms are not expected to apply in the case of flags of convenience.