A tie-in ship is a vessel built and owned by an overseas shipping company built at the request of a Japanese shipping company for the purpose of long-term charter. Under this system, introduced in 1970s, overseas shipping companies become eligible for loans from the Japan Bank for International Cooperation. For overseas shipping companies, this system can effectively reduce the costs of building vessels. At the same time, Japanese shipping companies can charter foreign vessels together with relatively cheap foreign crews, thus effectively cutting transportation costs. In addition to the simple tie-in by which a Japanese company commissions an overseas company to build and provide a vessel, there are other types of tie-in arrangements. A joint tie-in involves the Japanese and foreign company in a joint venture. For a complete tie-in, the Japanese company establishes a company overseas to commission the work.
In 1984, the U.S. congress passed a new maritime transport law characterized by the following: The law demands that the Federal Marine Committee, which regulates U.S marine transportation businesses, speed up its authorization process. At the same time, it requires all liner shipping conferences to stipulate independent action with regard to all shipping routes associated with the United States. This is a system in which shipping companies can set fees and services freely with 10 days notice, regardless of the conference agreement. The law also recognizes the service contract, allowing shippers to provide special services or fares to a consignor who has committed to send more than a given amount of cargo during a given period of time. This is in addition to the time volume rate, another type of large-volume discount.