It is undisputed that treaties can create binding obligations on individuals (physical human beings). However, the proposition that treaties may impose international legal obligations on collective non-state entities, such as private business corporations, remains controversial. Nevertheless, within the legal framework of the United Nations Convention on the Law of the Sea (UNCLOS) Part XI and Annex III, private business corporations (including the subsidiaries of some of the world’s leading mining, energy, and defence corporations) have been exploring areas of the Pacific, Indian, and Atlantic Oceans with the aim of exploiting natural resources from the deep seabed.

This chapter examines two key issues (and objections) relating to the imposition of binding obligations on collective non-state entities through a treaty: (i) the legal possibility of such binding regulation directly through a treaty, without the interposition of any state or municipal law; and (ii) the applicability and legal effects of the pacta tertiis rule, i.e. the classic rule that treaties bind only their parties and do not create rights or obligations for non-parties.