Under Article 76 of the Law of the Sea Convention each coastal state (sovereign country) has rights extending beyond the landmass. Many people incorrectly assume that simply locating a seastead more than 200 miles from shore makes it possible to establish a sovereign city-state.
A coastal nation may make a claim well beyond 200 miles based on the language in Article 76 regarding the Extended Continental Shelf (ECS). Within the 200 mile limit exists the Exclusive Economic Zone (EEZ) which gives control over the seafloor, including seabed and subsoil, as well as the column of water above the seabed. The extent of the ECS is determined by one of two formulae and, as a result, may extend beyond the EEZ. In this case sovereignty does not include the column of water but it does include the seabed and subsoil.
Article 76 specifically gives coastal nations sovereign rights and jurisdiction over construction, operation and use of artificial islands, installations and structures on the shelf. This jurisdiction also includes drilling on the continental shelf for any reason as well as any pipelines and prevention of marine pollution.
Article 76 appears to be a significant hurdle to the development of a permanent, politically-independent sovereign seastead.
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