A functional approach to reassessing the legal status and navigational rights of ships and ship-shaped structures

Wangwang Xing, Ling Zhu

Research output: Journal article publicationJournal articleAcademic researchpeer-review


Advancements in technology have prompted the emergence of several new kinds of ships and ship-shaped structures, including floating offshore platforms, unmanned maritime vehicles (UMVs), and unmanned merchant ships; this raises questions for international shipping regulations about their legal status and navigational rights. The legal status of a ship under the United Nations Convention on the Law of the Sea (UNCLOS), as well as other relevant international instruments, is different from that of a non-ship, since the latter does not have legal rights of international navigation. However, neither customary international law, nor the UNCLOS, provides a clear definition for the term “ship”, though different definitions of “ship” have been given in different international conventions and national statutes for their own purposes. This paper attempts to propose a functional approach, based on ships’ main functions of navigation and transportation, to reassessing the legal status and navigational rights of ships and ship-shaped structures. By following the functional approach, this paper clarifies that a ship having navigational rights means any self-propelled water-going vessel for the transportation of goods, passengers, and other objects, including vessels to be used for military or public service purposes. Based on this definition, the paper further finds that: 1) Floating offshore systems (including floating platforms and drill ships) should be regarded as ships when they are navigating in the waters; 2) most of the UMVs, being regarded as ship equipment or attachments, can only reflect their mother ship status; and 3) ocean-going bulkers and smaller container vessels that may be able to switch to unmanned operation should also be recognized as having the legal status of ships.

Original languageEnglish
Pages (from-to)120-130
Number of pages11
JournalTransport Policy
Publication statusPublished - Jun 2021


  • Legal status
  • Navigational right
  • Ship
  • Ship-shaped structure

ASJC Scopus subject areas

  • Geography, Planning and Development
  • Transportation

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