Law of the Sea

Introduction

The Law of the Sea is the branch of Public International Law that governs the legal status and use of the world’s oceans and seas.

It regulates:

• maritime zones;
• territorial sovereignty;
• navigation;
• passage of ships;
• exploitation of marine resources;
• fisheries;
• continental shelf rights;
• exclusive economic zones;
• deep seabed resources;
• marine environmental protection;
• marine scientific research;
• piracy;
• maritime disputes;
• settlement of disputes concerning the sea.

The modern law of the sea is largely codified in the United Nations Convention on the Law of the Sea, 1982 (UNCLOS).

UNCLOS is often described as the “constitution for the oceans.”

Historical Development

The law of the sea developed gradually through customary international law, State practice and international agreements.

Important stages include:

Traditional Freedom of the Seas

Historically, much of the high seas were regarded as open to all States.

The principle of freedom of the seas was strongly associated with the writings of Hugo Grotius, particularly Mare Liberum.

The basic idea was:

High Seas → Not subject to territorial sovereignty of individual States

Territorial Sea Development

States gradually claimed sovereignty over adjacent coastal waters.

The traditional three-mile rule became influential, although it was never universally accepted as the permanent maximum.

1958 Geneva Conventions

Four major conventions were adopted in 1958:

• Convention on the Territorial Sea and Contiguous Zone;
• Convention on the High Seas;
• Convention on Fishing and Conservation of the Living Resources of the High Seas;
• Convention on the Continental Shelf.

These were important stages in codifying the law of the sea.

UNCLOS 1982

UNCLOS was adopted on 10 December 1982 at Montego Bay, Jamaica.

It entered into force on 16 November 1994.

UNCLOS comprehensively regulates maritime zones and ocean activities.

United Nations Convention on the Law of the Sea

UNCLOS is the principal modern treaty governing the law of the sea.

It contains 320 articles and 9 annexes.

It addresses almost every major aspect of ocean governance.

Its framework includes:

Internal Waters

↓

Territorial Sea

↓

Contiguous Zone

↓

Exclusive Economic Zone

↓

Continental Shelf

↓

High Seas

↓

The Area

Maritime Zones

The most important maritime zones are:

• internal waters;
• territorial sea;
• contiguous zone;
• exclusive economic zone;
• continental shelf;
• high seas;
• the Area.

Each zone has a different legal regime.

Baseline

The baseline is the starting point from which the breadth of most maritime zones is measured.

The normal baseline is the low-water line along the coast as marked on officially recognised large-scale charts.

UNCLOS Articles 5–7 contain important rules concerning baselines.

Normal Baseline

Under Article 5, the normal baseline is the low-water line along the coast.

From this baseline, States measure:

• territorial sea;
• contiguous zone;
• exclusive economic zone;
• certain aspects of continental shelf entitlement.

Straight Baselines

Under Article 7, straight baselines may be used in appropriate geographical situations, particularly where:

• the coastline is deeply indented and cut into; or
• there is a fringe of islands along the coast in its immediate vicinity.

Straight baselines must not depart appreciably from the general direction of the coast.

Internal Waters

Article 8 deals with internal waters.

Internal waters are waters on the landward side of the baseline.

Examples may include:

• ports;
• certain bays;
• waters enclosed by valid straight baselines.

The coastal State generally exercises full sovereignty over internal waters.

Territorial Sea

The territorial sea is the maritime zone extending up to 12 nautical miles from the baseline.

This is provided by Article 3 UNCLOS.

The coastal State exercises sovereignty over:

• the territorial sea;
• the airspace above it;
• its seabed and subsoil.

However, that sovereignty is subject to important limitations, especially the right of innocent passage.

Territorial Sea Formula

Baseline

↓

Up to 12 nautical miles

↓

Territorial Sea

↓

Coastal State Sovereignty

Right of Innocent Passage

Innocent Passage

Articles 17–32 deal with passage through the territorial sea.

Ships of all States enjoy the right of innocent passage through the territorial sea.

Passage must be:

• continuous;
• expeditious;
• not prejudicial to the peace, good order or security of the coastal State.

Meaning of Passage

Under Article 18, passage includes navigation through the territorial sea for the purpose of:

• traversing that sea without entering internal waters; or
• proceeding to or from internal waters or a port facility.

When Passage Is Not Innocent

Under Article 19, passage is not innocent if it is prejudicial to the peace, good order or security of the coastal State.

Activities that may make passage non-innocent include:

• threat or use of force;
• weapons exercises;
• intelligence collection prejudicial to defence/security;
• propaganda affecting defence/security;
• launching or taking on board aircraft or military devices;
• loading or unloading contrary to customs, fiscal, immigration or sanitary laws;
• wilful pollution;
• fishing;
• research or survey activities;
• other activities not having a direct bearing on passage.

Submarines

Under Article 20, submarines and other underwater vehicles are required to navigate on the surface and show their flag while exercising innocent passage through the territorial sea.

Contiguous Zone

The contiguous zone extends up to 24 nautical miles from the baseline.

This is provided by Article 33 UNCLOS.

It is not equivalent to territorial sovereignty.

The coastal State may exercise necessary control to:

• prevent infringement of customs, fiscal, immigration or sanitary laws within its territory or territorial sea;
• punish infringement of those laws committed within its territory or territorial sea.

Territorial Sea vs Contiguous Zone

Territorial Sea	Contiguous Zone
Up to 12 nautical miles	Up to 24 nautical miles
Sovereignty	Limited enforcement/control jurisdiction
Innocent passage applies	No equivalent territorial sovereignty
Article 3	Article 33

Exclusive Economic Zone

The Exclusive Economic Zone (EEZ) is one of the most important innovations of UNCLOS.

Under Article 57, the EEZ may extend up to 200 nautical miles from the baselines.

The coastal State does not possess full sovereignty over the EEZ.

Instead, it has specific sovereign rights and jurisdiction.

Rights of the Coastal State in EEZ

Under Article 56, the coastal State has sovereign rights for:

• exploring;
• exploiting;
• conserving;
• managing natural resources.

These include:

Living Resources

Such as:

• fish;
• marine organisms.

Non-Living Resources

Such as:

• oil;
• gas;
• minerals.

The coastal State also has jurisdiction concerning:

• artificial islands and installations;
• marine scientific research;
• protection and preservation of the marine environment.

EEZ vs Territorial Sea

This is a very important examination distinction.

Territorial Sea	EEZ
Up to 12 nautical miles	Up to 200 nautical miles
Sovereignty	Sovereign rights + specified jurisdiction
Innocent passage	Navigation freedoms continue for other States
Article 3	Article 57
Territorial character	Functional economic zone

Rights of Other States in EEZ

Other States retain important freedoms in the EEZ, including:

• navigation;
• overflight;
• laying submarine cables and pipelines;

subject to the relevant provisions of UNCLOS.

Therefore, the EEZ is not an extension of the coastal State’s territorial sea.

Continental Shelf

The continental shelf concerns the seabed and subsoil of submarine areas extending beyond the territorial sea.

Under Article 76, the continental shelf comprises:

• seabed and subsoil of submarine areas;
• extending beyond the territorial sea throughout the natural prolongation of the land territory to the outer edge of the continental margin;

or

• to a distance of 200 nautical miles from the baselines where the outer edge of the continental margin does not extend that far.

Continental Shelf Rights

Under Article 77, the coastal State exercises sovereign rights over the continental shelf for the purpose of:

• exploring;
• exploiting its natural resources.

These rights are exclusive.

If the coastal State does not explore or exploit the shelf, another State cannot do so without its express consent.

Natural Resources of Continental Shelf

Resources include:

• mineral resources;
• other non-living resources;
• sedentary living organisms.

Continental Shelf vs EEZ

Continental Shelf	EEZ
Seabed and subsoil	Water column + seabed/subsoil aspects
Resource rights over seabed/subsoil	Broader economic rights and jurisdiction
Article 76	Article 57
Can extend beyond 200 nm subject to Article 76	Maximum 200 nm
Exists ipso facto and does not depend on proclamation	Generally requires establishment/claim within UNCLOS framework

Extended Continental Shelf

A coastal State may have a continental shelf extending beyond 200 nautical miles where the geographical requirements of Article 76 are satisfied.

The outer limits are subject to detailed technical rules.

The Commission on the Limits of the Continental Shelf (CLCS) plays an important role in considering submissions concerning the outer limits of the continental shelf beyond 200 nautical miles.

Commission on the Limits of the Continental Shelf

The CLCS is established under Annex II of UNCLOS.

Its principal role is to make recommendations to coastal States concerning the outer limits of their continental shelves beyond 200 nautical miles.

It does not determine maritime boundaries between States.

That distinction is important.

High Seas

The high seas are areas of the sea not included in:

• EEZ;
• territorial sea;
• internal waters;
• archipelagic waters.

The high seas are open to all States.

Freedom of the High Seas

Under Article 87, the freedom of the high seas includes, among other things:

• navigation;
• overflight;
• laying submarine cables and pipelines;
• construction of permitted artificial islands/installations;
• fishing;
• scientific research.

These freedoms must be exercised with due regard for the interests of other States.

Principle of Non-Appropriation

No State may validly claim sovereignty over the high seas.

Therefore:

High Seas

→ Freedom

→ No territorial sovereignty

Flag State Jurisdiction

Under Article 92, ships generally sail under the flag of one State and are subject to its jurisdiction on the high seas, subject to relevant exceptions.

The flag State exercises jurisdiction and control over ships flying its flag.

Warships

Warships generally enjoy immunity from the jurisdiction of States other than the flag State under Article 95 on the high seas.

Right of Visit

Under Article 110, a warship may exercise a right of visit in specified circumstances where there are reasonable grounds for suspecting that a ship is engaged in certain activities, such as:

• piracy;
• slave trade;
• unauthorised broadcasting;
• a ship without nationality;
• a ship of the same nationality in appropriate circumstances.

This is an exception to ordinary flag-State jurisdiction.

Piracy

Article 100 imposes a duty on all States to cooperate to the fullest possible extent in the repression of piracy.

Definition

Under Article 101, piracy includes certain illegal acts of violence, detention or depredation committed for private ends by the crew or passengers of a private ship or aircraft against another ship or aircraft, on the high seas or in a place outside the jurisdiction of any State.

Universal Jurisdiction Over Piracy

Piracy is traditionally recognised as a basis for universal jurisdiction.

A State may therefore take action against pirates even where there is no ordinary territorial or nationality connection, subject to UNCLOS and applicable international law.

Hot Pursuit

The doctrine of hot pursuit permits a coastal State, under specified conditions, to pursue a foreign ship beyond its territorial sea where the pursuit began while the ship was within waters under the coastal State’s jurisdiction.

Article 111 UNCLOS governs hot pursuit.

Conditions include:

• reasonable grounds for believing a violation occurred;
• pursuit must begin while the ship or one of its boats is within relevant waters;
• pursuit must be continuous;
• pursuit must not be interrupted in the prohibited manner;
• pursuit generally ends when the ship enters the territorial sea of its own State or a third State.

The Area

“The Area” means the seabed and ocean floor and subsoil thereof beyond the limits of national jurisdiction.

It is governed primarily by Part XI UNCLOS.

Common Heritage of Mankind

Under Article 136, the Area and its resources are the common heritage of mankind.

No State may claim sovereignty over the Area or its resources.

International Seabed Authority

The International Seabed Authority (ISA) was established under UNCLOS to organise and control activities in the Area.

Its functions include:

• regulating activities in the Area;
• administering mineral resources;
• protecting the marine environment;
• ensuring that the benefits of activities are dealt with according to the UNCLOS framework.

The Area vs High Seas

These concepts should not be confused.

High Seas

→ Water column beyond national maritime zones.

The Area

→ Seabed and subsoil beyond national jurisdiction.

Archipelagic States

UNCLOS recognises a special regime for archipelagic States.

An archipelagic State is a State constituted wholly by one or more archipelagos and may include other islands.

Under specified conditions, it may draw archipelagic baselines joining appropriate points of the outermost islands.

Archipelagic Waters

Waters enclosed by valid archipelagic baselines are known as archipelagic waters.

The archipelagic State exercises sovereignty over them, subject to UNCLOS limitations.

Important rights include:

• innocent passage;
• archipelagic sea lanes passage under applicable conditions.

Straits Used for International Navigation

UNCLOS establishes a special regime for certain straits used for international navigation.

The principal concept is:

Transit Passage

Under Articles 37–44, ships and aircraft enjoy the right of transit passage through straits used for international navigation between one part of the high seas or EEZ and another.

Transit Passage vs Innocent Passage

Transit Passage	Innocent Passage
Certain international straits	Territorial sea
Ships + aircraft	Primarily navigation by ships
Passage is continuous and expeditious	Passage must be innocent
Aircraft may overfly	No general equivalent right of overflight
Articles 37–44	Articles 17–19

Marine Scientific Research

UNCLOS contains rules concerning marine scientific research.

The coastal State has important authority over research in:

• territorial sea;
• EEZ;
• continental shelf.

Foreign States generally require the coastal State’s consent for research in the EEZ and on the continental shelf.

Marine Environmental Protection

Protection of the marine environment is a major component of UNCLOS.

Part XII deals with the Protection and Preservation of the Marine Environment.

States have a general obligation to protect and preserve the marine environment.

Article 192

Article 192 establishes the general obligation:

States have the obligation to protect and preserve the marine environment.

Article 194

States must take all measures consistent with UNCLOS that are necessary to prevent, reduce and control pollution of the marine environment.

Sources of pollution include:

• land-based sources;
• seabed activities;
• dumping;
• vessels;
• atmosphere.

Marine Pollution

UNCLOS addresses pollution resulting from:

• land-based activities;
• seabed activities;
• dumping;
• vessels;
• atmospheric sources.

The framework operates together with other specialised environmental treaties.

Fisheries

UNCLOS regulates fisheries in several maritime zones.

The coastal State exercises significant resource rights within the EEZ.

However, it must also:

• conserve living resources;
• take appropriate measures to prevent over-exploitation;
• cooperate concerning shared and highly migratory stocks.

Maximum Sustainable Yield

Article 61 requires coastal States to ensure that living resources are not endangered by over-exploitation.

States must consider relevant scientific evidence and seek to maintain or restore populations to levels that can produce maximum sustainable yield, subject to relevant environmental and economic considerations.

Straddling Fish Stocks

Fish stocks that move between:

• the EEZs of multiple States; or
• EEZs and adjacent high seas

create special problems.

UNCLOS provides a framework for cooperation.

The 1995 UN Fish Stocks Agreement further develops rules concerning:

• straddling fish stocks;
• highly migratory fish stocks;
• precautionary approaches;
• regional fisheries organisations.

Landlocked States

UNCLOS recognises certain rights of landlocked States, including rights concerning:

• access to and from the sea;
• transit through transit States under agreed arrangements.

Part X is relevant.

Maritime Boundaries

Where the maritime zones of two or more States overlap, the States may need to establish maritime boundaries.

UNCLOS provides different rules for different zones.

Territorial Sea Delimitation

Under Article 15, where the coasts of two States are opposite or adjacent, neither State is generally entitled to extend its territorial sea beyond the median line, unless:

• otherwise agreed; or
• historic title or other special circumstances justify a different boundary.

EEZ and Continental Shelf Delimitation

Articles 74 and 83 require delimitation of:

• EEZ between States with opposite or adjacent coasts;
• continental shelf between States with opposite or adjacent coasts.

The objective is to achieve an equitable solution.

Equidistance and Relevant Circumstances

International maritime delimitation jurisprudence has developed an approach involving:

• provisional equidistance line;
• relevant circumstances;
• adjustment where appropriate;
• disproportionality check.

The exact methodology depends upon the circumstances of the particular dispute.

Important Maritime Delimitation Cases

North Sea Continental Shelf Cases

The ICJ held that the equidistance method under the 1958 Continental Shelf Convention was not automatically binding on States that had not accepted it and emphasised equitable principles in delimitation.

Libya/Malta

The ICJ developed principles concerning continental shelf delimitation and the equitable result.

Qatar v Bahrain

Important for maritime delimitation and the legal status of maritime features.

Romania v Ukraine

The ICJ applied a structured methodology to maritime delimitation involving the Black Sea.

Bangladesh/Myanmar

The ITLOS judgment addressed maritime boundary delimitation in the Bay of Bengal.

Islands

Article 121 contains the principal rules concerning islands.

An island is a naturally formed area of land:

• surrounded by water;
• above water at high tide.

An island generally generates:

• territorial sea;
• contiguous zone;
• EEZ;
• continental shelf.

Rocks

Under Article 121(3):

Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf.

They may nevertheless have a territorial sea and contiguous zone where applicable.

Artificial Islands

Artificial islands do not have the same status as natural islands.

They do not possess:

• their own territorial sea;
• EEZ;
• continental shelf merely because they are constructed.

Maritime Zones Flowchart

Baseline

↓

Internal Waters

↓

Territorial Sea – 12 nm

↓

Contiguous Zone – 24 nm

↓

EEZ – 200 nm

↓

Continental Shelf – 200 nm or beyond under Article 76

↓

High Seas / The Area

Jurisdiction at Sea

Different States exercise different types of jurisdiction depending upon the maritime zone.

Coastal State

Exercises:

• sovereignty in territorial sea;
• limited enforcement powers in contiguous zone;
• sovereign rights and jurisdiction in EEZ;
• sovereign rights over continental shelf.

Flag State

Exercises jurisdiction over its vessels, particularly on the high seas.

Port State

May exercise jurisdiction over foreign vessels voluntarily entering its ports, subject to applicable international law.

Coastal State vs Flag State

Coastal State	Flag State
Territorial sovereignty	Jurisdiction over vessels
EEZ sovereign rights	Ship-related jurisdiction
Marine resource jurisdiction	High-seas jurisdiction
Environmental/enforcement powers	Flag-State responsibility

Port State Jurisdiction

A State may exercise jurisdiction over foreign ships voluntarily entering its ports.

Port-State control is particularly important concerning:

• safety;
• pollution;
• labour standards;
• vessel conditions.

Warships and Sovereign Immunity

Under Article 32, with specified exceptions, nothing in UNCLOS affects the immunities of warships and other government ships operated for non-commercial purposes.

UNCLOS and Maritime Dispute Settlement

UNCLOS provides a comprehensive dispute-settlement framework in Part XV.

States Parties are required to settle disputes concerning the interpretation or application of the Convention by peaceful means.

Article 279

States Parties must settle disputes concerning the interpretation or application of UNCLOS by peaceful means consistent with the UN Charter.

Article 287

States may choose among specified procedures for compulsory dispute settlement, including:

• International Tribunal for the Law of the Sea;
• International Court of Justice;
• arbitral tribunal constituted under Annex VII;
• special arbitral tribunal under Annex VIII.

ITLOS

The International Tribunal for the Law of the Sea (ITLOS) is an international judicial body established under UNCLOS.

Its seat is in Hamburg, Germany.

It has jurisdiction in matters assigned to it under UNCLOS and applicable agreements.

Annex VII Arbitration

Annex VII provides for arbitration as a major dispute-settlement mechanism.

It is particularly important because it can operate where the relevant compulsory procedure is engaged under UNCLOS, subject to applicable declarations and exceptions.

Annex VIII Special Arbitration

Annex VIII provides specialised arbitration for disputes concerning:

• fisheries;
• protection and preservation of the marine environment;
• marine scientific research;
• navigation.

Provisional Measures Under UNCLOS

UNCLOS provides mechanisms for provisional measures.

ITLOS can play an important role in urgent maritime disputes.

The tribunal may order measures designed to:

• preserve rights;
• prevent serious harm;
• protect the marine environment.

Important Law of the Sea Cases

S.S. Lotus (1927)

The Permanent Court of International Justice considered jurisdiction over a collision on the high seas and emphasised the importance of flag-State jurisdiction and the absence of a general prohibition unless established by international law.

Fisheries Jurisdiction

The ICJ’s Fisheries Jurisdiction cases addressed coastal-State fisheries rights and international obligations.

North Sea Continental Shelf

Important for continental shelf delimitation and customary international law.

Nicaragua v United States

Relevant to maritime activities, use of force and customary international law.

Qatar v Bahrain

Important for maritime delimitation and territorial/maritime sovereignty issues.

Guyana v Venezuela

Important for maritime and territorial issues and dispute settlement.

Bangladesh/Myanmar

ITLOS addressed maritime delimitation in the Bay of Bengal.

Philippines v China

The South China Sea Arbitration under Annex VII addressed major questions concerning maritime entitlements, historic rights and features under UNCLOS.

China did not participate in the arbitration, but the tribunal proceeded under the UNCLOS framework.

South China Sea Arbitration

The South China Sea Arbitration (Philippines v China) is one of the most significant modern UNCLOS cases.

The tribunal considered:

• maritime entitlements;
• status of maritime features;
• historic rights;
• environmental obligations;
• conduct affecting the marine environment.

The award is particularly important for the interpretation of Article 121 and UNCLOS maritime zones.

Freedom of Navigation

Freedom of navigation is a fundamental principle of the law of the sea.

However, the nature of the freedom depends upon the maritime zone.

For example:

Territorial Sea

→ Innocent passage

International Strait

→ Transit passage

EEZ

→ Navigation freedoms

High Seas

→ Freedom of navigation

Law of the Sea and National Security

UNCLOS interacts with national-security concerns involving:

• naval operations;
• warships;
• military exercises;
• maritime surveillance;
• navigation.

Questions concerning military activities in the EEZ have generated significant legal debate.

Piracy vs Armed Robbery at Sea

This distinction is important.

Piracy

Generally occurs on the high seas or outside the jurisdiction of any State and falls within the UNCLOS piracy framework.

Armed Robbery Against Ships

Generally occurs within the internal waters, archipelagic waters or territorial sea of a coastal State.

It is therefore primarily subject to the coastal State’s jurisdiction.

Law of the Sea and Maritime Resources

Marine resources include:

• fisheries;
• oil;
• gas;
• seabed minerals;
• renewable marine resources.

Different zones create different rights over those resources.

Important UNCLOS Articles

Remember the following:

Article 3 → Territorial sea: 12 nautical miles

Articles 5–7 → Baselines

Article 8 → Internal waters

Articles 17–19 → Innocent passage

Article 20 → Submarines in territorial sea

Article 33 → Contiguous zone: 24 nautical miles

Article 56 → EEZ rights

Article 57 → EEZ: 200 nautical miles

Article 61 → Conservation of living resources

Article 62 → Utilisation of living resources

Article 63 → Stocks occurring within/adjacent to EEZs

Article 74 → EEZ delimitation

Article 76 → Continental shelf

Article 77 → Continental shelf rights

Article 83 → Continental shelf delimitation

Article 87 → Freedom of high seas

Article 89 → No sovereignty over high seas

Article 92 → Flag-State jurisdiction

Article 95 → Warship immunity

Article 100 → Duty to cooperate against piracy

Article 101 → Definition of piracy

Article 110 → Right of visit

Article 111 → Hot pursuit

Article 121 → Islands

Article 136 → Common heritage of mankind

Article 192 → Protection of marine environment

Article 194 → Prevention of marine pollution

Article 279 → Peaceful settlement

Article 287 → Choice of dispute-settlement procedure

Article 288 → Jurisdiction

Maritime Zone Comparison

Zone	Maximum Extent	Coastal State Rights
Internal Waters	Landward of baseline	Sovereignty
Territorial Sea	12 nm	Sovereignty subject to innocent passage
Contiguous Zone	24 nm	Limited enforcement jurisdiction
EEZ	200 nm	Sovereign rights over resources + specified jurisdiction
Continental Shelf	At least 200 nm where applicable; potentially beyond	Sovereign rights over seabed/subsoil resources
High Seas	Beyond national maritime zones	No State sovereignty
The Area	Seabed beyond national jurisdiction	Common heritage of mankind

Law of the Sea and International Organisations

Several international institutions play important roles in the law of the sea:

International Tribunal for the Law of the Sea

Judicial settlement under UNCLOS.

International Seabed Authority

Administration of activities in the Area.

Commission on the Limits of the Continental Shelf

Recommendations concerning outer continental shelf limits.

International Maritime Organization

Develops international rules concerning maritime safety, shipping and prevention of pollution from ships.

Law of the Sea and IMO

The International Maritime Organization (IMO) is a specialised UN agency concerned with shipping.

It deals with matters including:

• maritime safety;
• maritime security;
• prevention of marine pollution from ships;
• shipping standards.

UNCLOS provides the broad legal framework, while specialised treaties adopted through the IMO regulate particular maritime activities.

Important Conventions Related to UNCLOS

The law of the sea operates together with other international instruments, including:

• MARPOL;
• SOLAS;
• STCW;
• 1995 UN Fish Stocks Agreement;
• 1958 Geneva Conventions on the Law of the Sea.

Law of the Sea and Environmental Law

Modern law of the sea increasingly connects:

Maritime Jurisdiction

with

Environmental Protection

States must exercise their maritime rights consistently with environmental obligations.

Precautionary Approach

The precautionary approach has become important in modern marine environmental governance, particularly concerning:

• fisheries;
• biodiversity;
• pollution;
• climate-related marine impacts.

Its precise legal status varies according to the applicable treaty and context.

Marine Biodiversity Beyond National Jurisdiction

Modern ocean law has expanded beyond traditional maritime zones.

The 2023 Agreement under UNCLOS on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction, commonly called the BBNJ Agreement, addresses biodiversity in areas beyond national jurisdiction.

Its major themes include:

• marine genetic resources;
• area-based management tools;
• environmental impact assessments;
• capacity-building;
• technology transfer.

It complements rather than replaces UNCLOS.

Importance of the Law of the Sea

The law of the sea is important because oceans cover the majority of the Earth’s surface and contain:

• major trade routes;
• fisheries;
• oil and gas;
• minerals;
• biodiversity;
• strategic waterways.

The legal regime attempts to balance:

Coastal State Sovereignty

Resource Rights

Freedom of Navigation

Environmental Protection

Interests of the International Community

Quick Revision

• Law of the Sea regulates the legal use of oceans and seas.
• The principal modern treaty is UNCLOS 1982.
• UNCLOS adopted → 10 December 1982.
• UNCLOS entered into force → 16 November 1994.
• UNCLOS → 320 Articles + 9 Annexes.
• Often called the constitution for the oceans.
• Baseline is the starting point for measuring maritime zones.
• Normal baseline → low-water line.
• Internal waters → sovereignty.
• Territorial sea → 12 nautical miles.
• Territorial sea → sovereignty subject to innocent passage.
• Contiguous zone → 24 nautical miles.
• Contiguous zone → limited enforcement jurisdiction.
• EEZ → 200 nautical miles.
• EEZ → sovereign rights, not full sovereignty.
• Continental shelf → seabed and subsoil.
• Continental shelf can extend beyond 200 nm under Article 76 if geographical conditions are satisfied.
• High seas → freedom and no territorial sovereignty.
• The Area → seabed beyond national jurisdiction.
• The Area and its resources → common heritage of mankind.
• ISA → International Seabed Authority.
• CLCS → Continental Shelf limits beyond 200 nm.
• ITLOS → Law of the Sea Tribunal.
• Article 3 → 12 nm territorial sea.
• Article 33 → 24 nm contiguous zone.
• Article 57 → 200 nm EEZ.
• Article 76 → Continental shelf.
• Article 87 → High seas freedoms.
• Article 101 → Piracy.
• Article 111 → Hot pursuit.
• Article 121 → Islands.
• Article 136 → Common heritage of mankind.
• Article 192 → Marine environmental protection.
• Article 287 → Dispute-settlement choices.
• Piracy is subject to universal jurisdiction under the UNCLOS framework.
• Innocent passage applies through the territorial sea.
• Transit passage applies through certain international straits.
• EEZ ≠ territorial sea.
• Continental shelf ≠ EEZ.
• High seas ≠ The Area.
• Artificial islands do not generate their own territorial sea, EEZ or continental shelf.
• Rocks incapable of sustaining human habitation or economic life of their own do not generate an EEZ or continental shelf under Article 121(3).
• Maritime delimitation seeks an equitable solution under Articles 74 and 83.
• Important cases:
  • S.S. Lotus;
  • Fisheries Jurisdiction;
  • North Sea Continental Shelf;
  • Qatar v Bahrain;
  • Bangladesh/Myanmar;
  • Philippines v China.

One-Line Memory Trick

Maritime Zones

“12 – 24 – 200”

12 nm → Territorial Sea

24 nm → Contiguous Zone

200 nm → EEZ

Resource Rights

Territorial Sea → Sovereignty

EEZ → Resources + Specified Jurisdiction

Continental Shelf → Seabed/Subsoil Resources

High Seas → Freedom

Area → Common Heritage

Passage

Territorial Sea → Innocent Passage

International Straits → Transit Passage

High Seas → Freedom of Navigation

Key Institutions

ITLOS → Disputes

ISA → The Area

CLCS → Continental Shelf Limits

IMO → Shipping Regulation

Conclusion

The Law of the Sea establishes a comprehensive legal framework for balancing the competing interests of coastal States, maritime States and the international community. The modern regime is centred on UNCLOS 1982, which codifies and develops rules concerning maritime zones, navigation, natural resources, environmental protection, scientific research and dispute settlement.

The most important conceptual distinction is between the different maritime zones. The territorial sea extends up to 12 nautical miles and is subject to coastal-State sovereignty, while the contiguous zone extends up to 24 nautical miles and gives the coastal State limited enforcement powers. The EEZ may extend up to 200 nautical miles and gives the coastal State sovereign rights over natural resources without converting the zone into territorial waters.

The continental shelf concerns the seabed and subsoil and may extend beyond 200 nautical miles where Article 76 permits. Beyond national maritime zones, the high seas remain open to all States, while the seabed beyond national jurisdiction—the Area—and its resources are treated as the common heritage of mankind.

UNCLOS also balances resource rights with freedoms of navigation and environmental responsibilities. Rules concerning innocent passage, transit passage, piracy, hot pursuit, marine scientific research and protection of the marine environment form essential parts of the system.

Finally, UNCLOS provides an extensive dispute-settlement framework involving ITLOS, the ICJ, Annex VII arbitration and Annex VIII special arbitration. Cases such as North Sea Continental Shelf, Qatar v Bahrain, Bangladesh/Myanmar and Philippines v China have significantly developed modern maritime law.

For examination purposes, remember the core formula:

12 nm → Territorial Sea

24 nm → Contiguous Zone

200 nm → EEZ

Continental Shelf → Seabed/Subsoil

High Seas → Freedom

The Area → Common Heritage of Mankind

UNCLOS → Constitution for the Oceans