Regulation, Law, Compliance and Governance

Public international law of the sea glossary

The UNCLOS framework for ocean governance: baselines and maritime zones (territorial sea, contiguous zone, EEZ, continental shelf, high seas, the Area), navigational regimes such as innocent, transit, and archipelagic sea-lanes passage, boundary delimitation and dispute settlement through ITLOS, the ICJ, and Annex VII tribunals, the International Seabed Authority, the BBNJ High Seas Treaty, and the polar regimes.

66 defined terms.

A

Abuse of Rights: Principle restraining excessive exercise of treaty rights, recognized in UNCLOS Article 300.
Annex VII Tribunal: Ad hoc arbitral tribunal constituted under UNCLOS Annex VII.
Archipelagic Sea Lanes Passage: Right of passage through archipelagic waters under UNCLOS Articles 53-54.
Archipelagic State: State constituted by archipelagos under UNCLOS Article 46.
Archipelagic Waters: Waters enclosed by archipelagic baselines.
Area, The: Seabed and subsoil beyond national jurisdiction, common heritage of mankind under UNCLOS Article 136.
Article 121 UNCLOS: Regime of islands, including the rocks rule in paragraph 3.
Article 234 UNCLOS: Ice-covered areas, allowing coastal-state regulation.

B

Baseline: Line from which the breadth of maritime zones is measured.
BBNJ Agreement 2023: Agreement under UNCLOS on Marine Biological Diversity of Areas Beyond National Jurisdiction.
Boundary Delimitation: Determination of maritime boundaries between adjacent or opposite states.

C

CLCS: Commission on the Limits of the Continental Shelf, established under UNCLOS Annex II.
Coastal State: State with sovereignty or jurisdiction over adjacent maritime zones.
Compulsory Procedures (UNCLOS Part XV): Dispute-settlement mechanisms entailing binding decisions.
Conciliation: Non-binding dispute mechanism under UNCLOS Annex V (used in Timor Sea case 2018).
Contiguous Zone: Zone up to 24 nm where the coastal state may enforce customs, fiscal, immigration, and sanitary laws (UNCLOS Article 33).
Continental Shelf: Seabed and subsoil beyond territorial sea, up to the outer edge of the continental margin or 200 nm.

D

Deep Seabed Mining: Activities in the Area, regulated by ISA under UNCLOS Part XI and the 1994 Implementing Agreement.
DOALOS: UN Division for Ocean Affairs and the Law of the Sea.
Due Regard: Standard of conduct between competing high seas freedoms (UNCLOS Article 87(2)).

E

EEZ: Exclusive Economic Zone, up to 200 nm under UNCLOS Part V.
Equidistance Principle: Default delimitation method, qualified by relevant circumstances.
Equity: Element in maritime boundary delimitation per ICJ jurisprudence.
Erga Omnes: Obligations owed to the international community as a whole.

F

Flag State: State of the ship's nationality, with jurisdiction under UNCLOS Article 94.
Flag State Genuine Link: Required under UNCLOS Article 91.
Freedom of the High Seas: Article 87 UNCLOS freedoms of navigation, overflight, cables, structures, fishing, and research.

H

High Seas: Waters beyond the EEZ under UNCLOS Part VII.
Hot Pursuit: Coastal-state right under UNCLOS Article 111.

I

ICJ: International Court of Justice, with maritime cases including North Sea Continental Shelf and Nicaragua v Colombia.
Innocent Passage: Right of foreign ships through the territorial sea under UNCLOS Articles 17-32.
Internal Waters: Waters landward of the baseline.
International Straits: Subject to transit passage under UNCLOS Part III.
ISA: International Seabed Authority based in Kingston, Jamaica.
ITLOS: International Tribunal for the Law of the Sea, Hamburg.

J

Jurisdiction (Coastal State): Functional rights in EEZ and on continental shelf under UNCLOS Parts V and VI.

L

Land-Locked State: Right of access to and from the sea under UNCLOS Article 125.
Law of the Sea Convention 1982: UNCLOS, in force 1994.
Lotus Principle: PCIJ doctrine of state sovereignty over flagged ships (Lotus, 1927), now qualified by UNCLOS.

M

Maritime Boundary: Line dividing maritime zones between states.
MOX Plant Case: ITLOS Order on provisional measures (2001).
MSR: Marine Scientific Research, regulated under UNCLOS Part XIII.

N

Nationality of Ships: Determined by flag state under UNCLOS Article 91.
Nicaragua v Colombia 2012: ICJ judgment on maritime delimitation in the Caribbean.

P

Pacta Sunt Servanda: Principle codified in Article 26 of the VCLT.
Part XII UNCLOS: Protection and preservation of the marine environment.
Part XV UNCLOS: Dispute settlement.
PCA: Permanent Court of Arbitration, registry for many UNCLOS Annex VII cases.
Piracy: Defined in UNCLOS Article 101.
Polar Code: Adopted under SOLAS XIV and MARPOL; complements Article 234 jurisdiction.
Provisional Measures: Interim measures under UNCLOS Article 290.

R

Reasonable Bond: Required for release of a vessel under UNCLOS Article 292 (Saiga, Camouco).
Regulating State: Coastal state authority over EEZ marine pollution under UNCLOS Article 211.
Right of Visit: Warship's right under UNCLOS Article 110.

S

Saiga No. 2 Case: ITLOS 1999 judgment on prompt release and use of force.
Search and Rescue: SAR Convention obligations parallel UNCLOS Article 98.
South China Sea Arbitration 2016: PCA award under UNCLOS Annex VII (Philippines v China).
Sovereign Immunity: Doctrine reflected in UNCLOS Articles 32, 95, and 96 for warships and government non-commercial ships.
Special Arbitration: Procedure under UNCLOS Annex VIII for fisheries, MSR, navigation, or pollution disputes.
Spitsbergen Treaty 1920: Multilateral treaty governing Svalbard sovereignty and access.
Straight Baselines: Permitted in specified geographic conditions under UNCLOS Article 7.
Submarine Cables: Freedom under UNCLOS Article 87 and Article 112.

T

Territorial Sea: Up to 12 nm under UNCLOS Article 3.
Transit Passage: Through straits used for international navigation under UNCLOS Article 38.

U

UNCLOS: United Nations Convention on the Law of the Sea, 1982.

V

VCLT 1969: Vienna Convention on the Law of Treaties.

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