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7 pages, Article 76, paragraph 1, of the United Nations Convention for the Law of the Sea (UNCLOS) establishes the entitlement of a coastal State to determine the outer limits of its continental shelf, and defines two different criteria to delimitate these outer limits based on either distance or nature of the submerged landmass. By default, the Convention states that the outer edge of the continental margin corresponds to a line delineated at a distance of 200 nautical miles from the baselines from which the breadth of the territorial sea is measured (the “reference distance” from here on). But this provision can be overcome in the case that the coastal State is able to demonstrate that the submerged land territory beyond this distance is a “natural prolongation” of the emerged landmass. This entitlement is evaluated by the Commission in reference to a “test of appurtenance” that consists on the factual demonstration of the natural prolongation of its land territory to the outer edge of the continental margin beyond the reference distance. This means that in the case that a State is able to demonstrate that the natural prolongation of its submerged land territory to the outer edge extends beyond the reference distance, its outer limit can be delineated by combination of two provisions in the form of the following complementary rules: (i) the thickness of the sedimentary rocks is at least 1% of the shortest distance from the “foot of continental slope” (FCS), or (ii) not more than 60 nautical miles from the FCS, and (iii) no further than a line delineated at a distance of 350 nautical miles from baselines, or (iv) no further than a line delineated at a distance of 100 nautical miles from the 2,500 m isobath. Submarine ridges constitute a special case where rule (iv) does not apply