The United Nations Convention on the Law of the Sea (UNCLOS), also called the Law of the Sea Convention or the Law of the Sea Treaty, is an international agreement that establishes a legal framework for all marine and maritime activities. , 167 countries and the
European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe Europe is a large peninsula conventionally considered a continent in its own right because of its gre ...
are parties. The Convention resulted from the third United Nations Conference on the Law of the Sea (UNCLOS III), which took place between 1973 and 1982. UNCLOS replaced the four treaties of the 1958 Convention on the High Seas. UNCLOS came into force in 1994, a year after Guyana became the 60th nation to ratify the treaty. It is uncertain as to what extent the Convention codifies customary international law. While the
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receives instruments of
ratification Ratification is a principal's approval of an act of its agent that lacked the authority to bind the principal legally. Ratification defines the international act in which a state indicates its consent to be bound to a treaty if the parties inte ...
and accession and the UN provides support for meetings of states party to the Convention, the United Nations Secretariat has no direct operational role in the implementation of the Convention. A UN
specialized agency United Nations Specialized Agencies are autonomous organizations working with the United Nations The United Nations (UN) is an intergovernmental organization Globalization is social change associated with increased connectivity am ...
, the
International Maritime Organization The International Maritime Organization (IMO, French: ''Organisation maritime internationale'') is a specialised agency of the United Nations responsible for regulating shipping. The IMO was established following agreement at a UN conferenc ...
, does play a role, however, as well as other bodies such as the International Whaling Commission and the International Seabed Authority (ISA), which was established by the Convention itself.


UNCLOS replaces the older ' freedom of the seas' concept, dating from the 17th century. According to this concept, national rights were limited to a specified belt of water extending from a nation's
coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth Earth is the third planet from the Sun an ...
lines, usually ( three-mile limit), according to the '
cannon A cannon is a large- caliber gun classified as a type of artillery Artillery is a class of heavy military ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery developm ...
shot' rule developed by the Dutch jurist Cornelius van Bynkershoek. All waters beyond national boundaries were considered
international waters The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, ...
: free to all nations, but belonging to none of them (the '' mare liberum'' principle promulgated by
Hugo Grotius Hugo Grotius (; 10 April 1583 – 28 August 1645), also known as Huig de Groot () and Hugo de Groot (), was a Dutch humanist, diplomat, lawyer, theologian, jurist, poet and playwright. A teenage intellectual prodigy, he was born in Del ...
). In the early 20th century, some nations expressed their desire to extend national claims: to include mineral resources, to protect fish stocks, and to provide the means to enforce pollution controls. (The
League of Nations The League of Nations (french: link=no, Société des Nations ) was the first worldwide intergovernmental organisation whose principal mission was to maintain world peace. It was founded on 10 January 1920 by the Paris Peace Conference th ...
called a 1930 conference at
The Hague The Hague ( ; nl, Den Haag or ) is a city and municipality of the Netherlands, situated on the west coast facing the North Sea. The Hague is the country's administrative centre and its seat of government, and while the official capita ...
, but no agreements resulted.) Using the customary international law principle of a nation's right to protect its natural resources, President Harry S. Truman in 1945 extended United States control to all the natural resources of its
continental shelf A continental shelf is a portion of a continent A continent is any of several large landmass A landmass, or land mass, is a large region or area of land. The term is often used to refer to lands surrounded by an ocean or sea, ...
. Other nations were quick to follow suit. Between 1946 and 1950, Chile, Peru, and Ecuador extended their rights to a distance of to cover their Humboldt Current fishing grounds. Other nations extended their territorial seas to . By 1967, only 25 nations still used the old three nautical mile limit, while 66 nations had set a territorial limit and eight had set a limit. , only Jordan still uses the limit. That limit is also used in certain Australian islands, an area of Belize, some Japanese
strait A strait is an oceanic landform connecting two seas or two other large areas of water. The surface water generally flows at the same elevation on both sides and through the strait in either direction. Most commonly, it is a narrow ocean cha ...
s, certain areas of Papua New Guinea, and a few
British Overseas Territories The British Overseas Territories (BOTs), also known as the United Kingdom Overseas Territories (UKOTs), are fourteen territories with a constitutional and historical link with the United Kingdom The United Kingdom of Great Britain ...
, such as
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. UNCLOS does not deal with matters of territorial disputes or to resolve issues of sovereignty, as that field is governed by rules of customary international law on the acquisition and loss of territory. The United Nations Sustainable Development Goal 14 has a target regarding conservative and sustainable use of oceans and their resources in line with UNCLOS legal framework.


In 1956, the United Nations held its first Conference on the Law of the Sea (UNCLOS I) at
Geneva Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevra ; rm, Genevra is the second-most populous city in Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government ...
, Switzerland. UNCLOS I resulted in four treaties concluded in 1958: * Convention on the Territorial Sea and Contiguous Zone, entry into force: 10 September 1964 * Convention on the Continental Shelf, entry into force: 10 June 1964 * Convention on the High Seas, entry into force: 30 September 1962 * Convention on Fishing and Conservation of Living Resources of the High Seas, entry into force: 20 March 1966 Although UNCLOS I was considered a success, it left open the important issue of breadth of territorial waters.


In 1960, the United Nations held the second Conference on the Law of the Sea ("UNCLOS II"); however, the six-week Geneva conference did not result in any new agreements. Generally speaking, developing nations and third world countries participated only as clients, allies, or dependents of the United States or the Soviet Union, with no significant voice of their own.


The issue of varying claims of territorial waters was raised in the UN in 1967 by Arvid Pardo of Malta, and in 1973 the ''Third United Nations Conference on the Law of the Sea'' convened in New York. In an attempt to reduce the possibility of groups of nation-states dominating the negotiations, the conference used a consensus process rather than majority vote. With more than 160 nations participating, the conference lasted until 1982. The resulting convention came into force on 16 November 1994, one year after the 60th state, Guyana, ratified the treaty. The convention introduced a number of provisions. The most significant issues covered were setting limits, navigation, archipelagic status and transit regimes, exclusive economic zones (EEZs), continental shelf jurisdiction, deep seabed mining, the exploitation regime, protection of the marine environment, scientific research, and settlement of disputes. The convention set the limit of various areas, measured from a carefully defined baseline. (Normally, a sea baseline follows the low-water line, but when the coastline is deeply indented, has fringing islands or is highly unstable, straight baselines may be used.) The areas are as follows: ; Internal waters:Covers all water and waterways on the landward side of the baseline. The coastal state is free to set laws, regulate use, and use any resource. Foreign vessels have no right of passage within internal waters. A vessel in the high seas assumes jurisdiction under the internal laws of its flag State. ; Territorial waters: Out to from the baseline, the coastal state is free to set laws, regulate use, and use any resource. Vessels were given the right of innocent passage through any territorial waters, with strategic straits allowing the passage of military craft as
transit passage Transit passage is a concept of the law of the sea, which allows a vessel or aircraft the freedom of navigation or overflight solely for the purpose of continuous and expeditious transit of a strait between one part of the high seas or exclusiv ...
, in that naval vessels are allowed to maintain postures that would be illegal in territorial waters. "Innocent passage" is defined by the convention as passing through waters in an expeditious and continuous manner, which is not "prejudicial to the peace, good order or the security" of the coastal state. Fishing, polluting, weapons practice, and spying are not "innocent", and submarines and other underwater vehicles are required to navigate on the surface and to show their flag. Nations can also temporarily suspend innocent passage in specific areas of their territorial seas, if doing so is essential for the protection of their security. ; Archipelagic waters: The convention set the definition of "Archipelagic States" in Part IV, which also defines how the state can draw its territorial borders. A baseline is drawn between the outermost points of the outermost islands, subject to these points being sufficiently close to one another. All waters inside this baseline are designated "Archipelagic Waters". The state has sovereignty over these waters mostly to the extent it has over internal waters, but subject to existing rights including traditional fishing rights of immediately adjacent states. Foreign vessels have right of innocent passage through archipelagic waters, but archipelagic states may limit innocent passage to designated sea lanes. ; Contiguous zone:Beyond the limit, there is a further from the territorial sea baseline limit, the contiguous zone. Here a state can continue to enforce laws in four specific areas (customs, taxation, immigration, and pollution) if the infringement started or is about to occur within the state's territory or territorial waters. This makes the contiguous zone a hot pursuit area. ; Exclusive economic zones (EEZs): These extend from the baseline. Within this area, the coastal nation has sole exploitation rights over all natural resources. In casual use, the term may include the territorial sea and even the continental shelf. The EEZs were introduced to halt the increasingly heated clashes over fishing rights, although oil was also becoming important. The success of an offshore
oil platform An oil platform (or oil rig, offshore platform, oil production platform, and similar terms) is a large structure with facilities to extract and process petroleum Petroleum, also known as crude oil, or simply oil, is a naturally occurrin ...
in the
Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...
in 1947 was soon repeated elsewhere in the world, and by 1970 it was technically feasible to operate in waters deep. Foreign nations have the freedom of navigation and overflight, subject to the regulation of the coastal states. Foreign states may also lay submarine pipes and cables. ;
Continental shelf A continental shelf is a portion of a continent A continent is any of several large landmass A landmass, or land mass, is a large region or area of land. The term is often used to refer to lands surrounded by an ocean or sea, ...
: The continental shelf is defined as the natural prolongation of the land territory to the continental margin's outer edge, or from the coastal state's baseline, whichever is greater. A state's continental shelf may exceed until the natural prolongation ends. However, it may never exceed from the baseline; nor may it exceed beyond the isobath (the line connecting the depth of 2 500 m). Coastal states have the right to harvest mineral and non-living material in the subsoil of its continental shelf, to the exclusion of others. Coastal states also have exclusive control over living resources "attached" to the continental shelf, but not to creatures living in the
water column A water column is a concept Concepts are defined as abstract ideas. They are understood to be the fundamental building blocks of the concept behind principles, thoughts and beliefs. They play an important role in all aspects of cognition. ...
beyond the exclusive economic zone. The area outside these areas is referred to as the "
high seas The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, ...
" or simply "the Area". Aside from its provisions defining ocean boundaries, the convention establishes general obligations for safeguarding the marine environment and protecting freedom of scientific research on the high seas, and also creates an innovative legal regime for controlling mineral resource exploitation in deep seabed areas beyond national jurisdiction, through an International Seabed Authority and the common heritage of mankind principle. Landlocked states are given a right of access to and from the sea, without taxation of traffic through transit states.

Part XI and the 1994 Agreement

Part XI of the Convention provides for a regime relating to minerals on the seabed outside any state's territorial waters or EEZ (Exclusive Economic Zones). It establishes an International Seabed Authority (ISA) to authorize seabed exploration and mining and collect and distribute the seabed mining royalty. The United States objected to the provisions of Part XI of the Convention on several grounds, arguing that the treaty was unfavorable to American economic and security interests. Due to Part XI, the United States refused to ratify the UNCLOS, although it expressed agreement with the remaining provisions of the Convention. From 1982 to 1990, the United States accepted all but Part XI as customary international law, while attempting to establish an alternative regime for exploitation of the minerals of the deep seabed. An agreement was made with other seabed mining nations and licenses were granted to four international consortia. Concurrently, the Preparatory Commission was established to prepare for the eventual coming into force of the Convention-recognized claims by applicants, sponsored by signatories of the Convention. Overlaps between the two groups were resolved, but a decline in the demand for minerals from the seabed made the seabed regime significantly less relevant. In addition, the decline of Communism in the late 1980s removed much of the support for some of the more contentious Part XI provisions. In 1990, consultations began between signatories and non-signatories (including the United States) over the possibility of modifying the Convention to allow the industrialized countries to join the Convention. The resulting 1994 Agreement on Implementation was adopted as a binding international Convention. It mandated that key articles, including those on limitation of seabed production and mandatory technology transfer, would not be applied, that the United States, if it became a member, would be guaranteed a seat on the Council of the International Seabed Authority, and finally, that voting would be done in groups, with each group able to block decisions on substantive matters. The 1994 Agreement also established a Finance Committee that would originate the financial decisions of the Authority, to which the largest donors would automatically be members and in which decisions would be made by consensus. On 1 February 2011, the Seabed Disputes Chamber of the International Tribunal for the Law of the Sea (ITLOS) issued an advisory opinion concerning the legal responsibilities and obligations of States Parties to the Convention with respect to the sponsorship of activities in the Area in accordance with Part XI of the Convention and the 1994 Agreement. The advisory opinion was issued in response to a formal request made by the International Seabed Authority following two prior applications the Authority's Legal and Technical Commission had received from the Republic of Nauru and the Kingdom of Tonga regarding proposed activities (a plan of work to explore for polymetallic nodules) to be undertaken in the Area by two State-sponsored contractors – Nauru Ocean Resources Inc. (sponsored by the Republic of Nauru) and Tonga Offshore Mining Ltd. (sponsored by the Kingdom of Tonga). The advisory opinion set forth the international legal responsibilities and obligations of Sponsoring States and the Authority to ensure that sponsored activities do not harm the marine environment, consistent with the applicable provisions of UNCLOS Part XI, Authority regulations, ITLOS case law, other international environmental treaties, and Principle 15 of the UN Rio Declaration.

Part XII – Protecting the marine environment

Part XII of UNCLOS contains special provisions for the protection of the marine environment, obligating all States to collaborate in this matter, as well as placing special obligations on flag States to ensure that ships under their flags adhere to international environmental regulations, often adopted by the IMO. The MARPOL Convention is an example of such regulation. Part XII also bestows coastal and port states with broadened jurisdictional rights for enforcing international environmental regulation within their territory and on the
high seas The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, ...

Biodiversity beyond national jurisdiction

In 2017, the
United Nations General Assembly The United Nations General Assembly (UNGA or GA; french: link=no, Assemblée générale, AG) is one of the six principal organs of the United Nations (UN), serving as the main deliberative, policymaking, and representative organ of the UN. Cur ...
(UNGA) voted to convene an intergovernmental conference (IGC) to consider establishing an international legally-binding instrument (ILBI) on the conservation and sustainable use of biodiversity beyond national jurisdiction (BBNJ). This is considered necessary because UNCLOS does not currently provide a framework for areas beyond national jurisdiction. There is a particular concern for marine biodiversity and the impact of overfishing on global fish stocks and ecosystem stability. The IGC convened a total of four sessions in 2018, 2019, and 2022 to negotiate the text for the BBNJ legal instrument. Progress was made in the four main elements: marine genetic resources (MGRs), benefit sharing using area-based management tools (ABMTs) including marine protected areas (MPAs), environmental impact assessments (EIAs) and capacity building and the transfer of marine technology (CB&TT). A fifth round of talks in August 2022 failed to produce an agreement, due in part to significant disagreements over how to share benefits derived from marine genetic resources and digital sequence information.


The convention was opened for signature on 10 December 1982 and entered into force on 16 November 1994 upon deposition of the 60th instrument of ratification. The convention has been ratified by 168 parties, which includes 164 UN member states, 1 UN Observer state ( Palestine) and two associated countries (the
Cook Islands ) , image_map = Cook Islands on the globe (small islands magnified) (Polynesia centered).svg , capital = Avarua , coordinates = , largest_city = Avarua , official_languages = , lan ...
Niue Niue (, ; niu, Niuē) is an island country in the South Pacific Ocean, northeast of New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean The Pacific Ocean is the largest a ...
) plus the
European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe Europe is a large peninsula conventionally considered a continent in its own right because of its gre ...


The significance of UNCLOS stems from the fact that it systemizes and codifies the standards and principles of international maritime law, which are based on centuries of maritime experience and are expressed to a great extent in the United Nations Charter and current international maritime law norms, such as the Geneva Conventions of 1958. A large portion of these requirements were further strengthened and expanded.capt. Enchev, V. (2012), Fundamentals of Maritime Law

See also

* * * * * * * * * * * * * * * * * * * List of territories governed by the United Nations

Further reading

* Sara McLaughlin Mitchell and Andrew P. Owsiak. 2021.
Judicialization of the Sea: Bargaining in the Shadow of UNCLOS
" ''American Journal of International Law.''


External links


* ttp://www.itlos.org/ International Tribunal for the Law of the Sea
Permanent Court of Arbitration – Past and Pending Cases

Decisions of the World Court Relevant to the UNCLOS (2010)
Contents & Indexes

* ttps://www.un.org/Depts/los/clcs_new/clcs_home.htm UN Commission on the Limits of the Continental Shelf*  
UNEP Shelf Programme, UN organisation set up to assist States in delineating their continental shelf beyond 200 nautical miles (370 km)

EEZ/CS Boundaries Canadian Database

Digital Map of the World's Exclusive Economic Zones

SOPAC Maritime Boundaries Database

procedural history note and audiovisual material on the ''1958 Geneva Conventions on the Law of the Sea'' in th

* ttp://legal.un.org/avl/ha/uncls/uncls.html Introductory note by Tullio Treves procedural history note and audiovisual material on the ''United Nations Convention on the Law of the Sea'' in th
Historic Archives of the United Nations Audiovisual Library of International Law
{{DEFAULTSORT:Law of the Sea Convention 1994 in the environment * Convention on the Law of the Sea United Nations Convention on the Law of the Sea United Nations Convention on the Law of the Sea United Nations Convention on the Law of the Sea United Nations Convention on the Law of the Sea Treaties of Albania Treaties of Algeria Treaties of the People's Republic of Angola Treaties of Antigua and Barbuda Treaties of Argentina Treaties of Armenia Treaties of Australia Treaties of Austria Treaties of Azerbaijan Treaties of the Bahamas Treaties of Bahrain Treaties of Bangladesh Treaties of Barbados Treaties of Belarus Treaties of Belgium Treaties of Belize Treaties of Benin Treaties of Bolivia Treaties of Bosnia and Herzegovina Treaties of Botswana Treaties of Brazil Treaties of Brunei Treaties of Bulgaria Treaties of Burkina Faso Treaties of Cameroon Treaties of Canada Treaties of Cape Verde Treaties of Chad Treaties of Chile Treaties of the People's Republic of China Treaties of the 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Treaties of the Yemen Arab Republic Treaties of Yugoslavia Treaties of Zambia Treaties of Zimbabwe Treaties entered into by the European Union 1982 in Jamaica United Nations Convention on the Law of the Sea Treaties establishing intergovernmental organizations Treaties extended to Aruba Treaties extended to the Netherlands Antilles Treaties extended to Jersey Treaties extended to Guernsey Treaties extended to the Isle of Man Treaties extended to Anguilla Treaties extended to Bermuda Treaties extended to the British Antarctic Territory Treaties extended to the British Indian Ocean Territory Treaties extended to the British Virgin Islands Treaties extended to the Cayman Islands Treaties extended to the Falkland Islands Treaties extended to Gibraltar Treaties extended to Montserrat Treaties extended to the Pitcairn Islands Treaties extended to Saint Helena, Ascension and Tristan da Cunha Treaties extended to South Georgia and the South Sandwich Islands Treaties extended to the Turks and Caicos Islands Treaties extended to the Faroe Islands Treaties extended to Greenland