A sea zone extending up to 200 nautical miles from a coastal state's baseline where it has sovereign rights over resources.
In practice
For a master, the EEZ is operationally significant because MARPOL enforcement — particularly for Annex I and Annex V violations — extends throughout the zone. A coastal state may inspect a vessel suspected of discharging in its EEZ, and many states exercise this right actively. Vessels arrested for MARPOL violations within the EEZ of a state that is a party to the Convention can face prosecution in that state's courts.
Regulatory detail & full definition
The Exclusive Economic Zone is a maritime zone defined by UNCLOS Article 57 as extending up to 200 nautical miles from the baseline from which the territorial sea is measured. Within the EEZ, the coastal state has sovereign rights for the purpose of exploring, exploiting, conserving, and managing the natural resources of the waters, seabed, and subsoil. The coastal state also has jurisdiction over marine scientific research and the protection of the marine environment within its EEZ.
For a master, the EEZ is operationally significant because MARPOL enforcement — particularly for Annex I and Annex V violations — extends throughout the zone. A coastal state may inspect a vessel suspected of discharging in its EEZ, and many states exercise this right actively. Vessels arrested for MARPOL violations within the EEZ of a state that is a party to the Convention can face prosecution in that state's courts.
The EEZ does not restrict freedom of navigation in the same way as the territorial sea. Ships may transit, lay cables and pipelines, and conduct other internationally lawful uses of the sea. However, fishing vessels require authorisation from the coastal state. The outer boundary of overlapping EEZs between neighbouring states is frequently subject to maritime boundary disputes, which can affect the legal regime applicable to a vessel at a given position.