SUBJECT: The Rule on ‘The Exclusive Economic Zone’ (EEZ) under UNCLOS

I. Introduction

This memorandum provides an exhaustive analysis of the rule on the Exclusive Economic Zone (EEZ) under the United Nations Convention on the Law of the Sea (UNCLOS). The EEZ represents a fundamental innovation in the modern law of the sea, creating a sui generis zone beyond the territorial sea where coastal states exercise specific sovereign rights and jurisdiction, balanced by the freedoms of other states. This memo will delineate the legal framework, rights and duties of coastal and other states, delimitation principles, and enforcement mechanisms as established primarily in Part V of UNCLOS.

II. Definition and Legal Character of the EEZ

The Exclusive Economic Zone is an area beyond and adjacent to the territorial sea, extending to a maximum of 200 nautical miles from the baselines from which the breadth of the territorial sea is measured. Its legal character is distinct from both the territorial sea (full sovereignty) and the high seas (freedom of the seas). The EEZ is a zone of functional jurisdiction where the coastal state does not possess full sovereignty but enjoys, as articulated in Article 56 of UNCLOS, “sovereign rights for the purpose of exploring and exploiting, conserving and managing the natural resources, whether living or non-living,” as well as jurisdiction over specific activities. This hybrid nature necessitates a careful balancing of interests between the coastal state and the international community.

III. Rights and Jurisdiction of the Coastal State

Pursuant to Article 56 of UNCLOS, within its EEZ, the coastal state enjoys:

Sovereign rights for the purpose of exploring, exploiting, conserving, and managing all natural resources, both living (fish, mammals) and non-living (oil, gas, minerals) in the waters superjacent to the seabed, the seabed, and its subsoil.

Sovereign rights regarding other activities for the economic exploitation and exploration of the zone, such as the production of energy from water, currents, and winds.

Jurisdiction as provided for under relevant UNCLOS provisions concerning:

a. The establishment and use of artificial islands, installations, and structures (Article 60).
b. Marine scientific research (Article 56(1)(b)(ii) and Part XIII).
c. The protection and preservation of the marine environment (Article 56(1)(b)(iii) and Part XII).

Other rights and duties provided for under UNCLOS, including those related to the laying of submarine cables and pipelines (Article 58(1)), though this is a right also enjoyed by other states.

IV. Rights and Duties of Other States

Article 58 of UNCLOS guarantees that in the EEZ, all states, whether coastal or land-locked, enjoy the freedoms of navigation and overflight, and of the laying of submarine cables and pipelines, and other internationally lawful uses of the sea related to these freedoms. These freedoms must be exercised with due regard for the rights and duties of the coastal state and in compliance with its laws and regulations adopted in conformity with UNCLOS. Other states also have the duty to comply with the coastal state’s laws concerning resource-related matters, artificial islands, marine scientific research, and marine environmental protection. The freedoms exercised are those of the high seas, but they are not absolute within the EEZ as they are subject to the specific legal regime of the zone.

V. Delimitation of the EEZ between Adjacent or Opposite States

Article 74 of UNCLOS governs the delimitation of the EEZ between states with opposite or adjacent coasts. It provides that such delimitation “shall be effected by agreement on the basis of international law, as referred to in Article 38 of the Statute of the International Court of Justice, in order to achieve an equitable solution.” The article does not prescribe a specific method (e.g., equidistance), reflecting the contentious negotiations during UNCLOS III. State practice and international jurisprudence (e.g., North Sea Continental Shelf Cases, Libya/Malta Case) have developed a standard approach: delimitation begins by drawing a provisional equidistance line, which is then adjusted based on relevant circumstances to achieve an equitable solution. Relevant circumstances may include geography (coastal configuration, presence of islands), conduct of the parties, and a reasonable degree of proportionality between the length of the relevant coasts and the maritime areas allocated.

VI. Natural Resources Management and Conservation

A core component of the coastal state’s sovereign rights is the duty to ensure the conservation and optimum utilization of living resources. Articles 61 and 62 of UNCLOS impose specific obligations:

Determination of Allowable Catch: The coastal state must determine the total allowable catch (TAC) of living resources in its EEZ, taking into account the best scientific evidence available to ensure resources are not endangered by over-exploitation (conservation).

Promotion of Optimum Utilization: Where the coastal state does not have the capacity to harvest the entire TAC, it is obliged, through agreements or other arrangements, to give other states access to the surplus, paying particular regard to land-locked and geographically disadvantaged states, as well as developing states in the region (optimum utilization).

Regulation of Access: The coastal state establishes laws and regulations for foreign access, which may relate to licensing, fees, catch quotas, species, and areas.

VII. Comparative Table: Key Features of Maritime Zones under UNCLOS

Feature	Territorial Sea (Part II)	Contiguous Zone (Part II)	Exclusive Economic Zone (Part V)	High Seas (Part VII)
Maximum Breadth	12 nautical miles	24 nautical miles (from baselines)	200 nautical miles (from baselines)	Beyond EEZ/territorial sea
Coastal State Rights	Full sovereignty, subject to right of innocent passage	Limited control to prevent/infringe customs, fiscal, immigration, sanitary laws	Sovereign rights over resources; jurisdiction over artificial islands, MSR, environment	None (flag state jurisdiction prevails)
Key Freedoms of Other States	Innocent passage (continuous & expeditious)	Freedom of navigation and overflight	Freedoms of navigation, overflight, laying cables/pipelines (with due regard)	Full freedoms of the high seas
Resource Rights	Exclusive	None	Exclusive sovereign rights over all natural resources	Freedom of fishing (subject to treaties)
Legal Basis for Enforcement	Coastal state’s sovereign authority	Specific preventive/punitive powers for listed offenses	Enforcement of resource, environmental, and installation-related laws	Primarily flag state jurisdiction

VIII. Artificial Islands, Installations, and Structures

Under Article 60, the coastal state has the exclusive right to construct and to authorize and regulate the construction, operation, and use of artificial islands, and all installations and structures for economic purposes or those that may interfere with its rights in the EEZ. The coastal state has exclusive jurisdiction over such artificial islands, installations, and structures, including jurisdiction with regard to customs, fiscal, health, safety, and immigration laws. It may establish reasonable safety zones around them, not exceeding 500 meters, and must ensure their removal when abandoned or disused to ensure safety of navigation. Due notice must be given of their construction, and permanent means for warning of their presence must be maintained.

IX. Settlement of Disputes

Disputes concerning the interpretation or application of UNCLOS provisions regarding the EEZ are subject to the compulsory dispute settlement mechanisms under Part XV of UNCLOS. A state party is generally obliged to submit such disputes to a court or tribunal with jurisdiction under the Convention, which includes the International Tribunal for the Law of the Sea (ITLOS), the International Court of Justice (ICJ), or an arbitral tribunal. However, Article 298 allows states to make declarations excluding certain categories of disputes, including those involving maritime boundary delimitation or military activities, from compulsory procedures. For such excluded disputes, compulsory conciliation may still apply under specific conditions.

X. Conclusion

The Exclusive Economic Zone under UNCLOS establishes a sophisticated and balanced legal regime that reconciles the extension of coastal state resource jurisdiction with the preservation of key high seas freedoms for the international community. Its success lies in its detailed articulation of rights, duties, and obligations for both coastal and other states, covering resource management, environmental protection, and scientific research. While the regime is well-defined, its application continues to evolve through state practice and international jurisprudence, particularly in areas of delimitation, enforcement, and balancing competing uses. The EEZ remains a cornerstone of the modern law of the sea, fundamentally shaping ocean governance.