They involved agreements among Denmark, Germany, and the Netherlands regarding the "delimitation" of areas, rich in oil and gas, of the continental shelf in the North Sea.

If the delimitation had been determined by the equidistance rule ("drawing a line each point of which is equally distant from each shore"), Germany would have received a smaller portion of the resource-rich shelf relative to the two other states.

Notably, Denmark and the Netherlands had ratified the 1958 Geneva Continental Shelf Convention, unlike the Federal Republic of Germany, which wished for Article 6, p. 2 (equidistance principle) to be applied: Article 6 An important question the Court answered was if the equidistance principle was, at the date of the ruling, a customary international law binding on all States.

Moreover, as stated in para 77, the practice must also, as a subjective element, stem from a notion of opinio juris sive necessitatis.

The Court ultimately urged the parties to "abat[e] the effects of an incidental special feature [Germany's concave coast] from which an unjustifiable difference of treatment could result".