2.1 Introduction
This chapter analyzes the scope of the non-appropriation principle and assesses its impact on the potential exploitation of natural resources in outer space. The non-appropriation principle is incorporated in Article II of the Outer Space Treaty [OST]. The provision codifies a fundamental principle regulating outer space. It stipulates:
“Outer space, including the moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.” (1) The OST (n. 21), supra.
As the OST is silent on the legal status of natural resources in outer space, questions arise regarding the scope and impact of Article II regarding natural resources in outer space: How does the non-appropriation principle, if at all, affect the potential exploitation of said resources? Leading scholars in the field have for a long time addressed the question, but their conclusions are of similar nature: Whether natural resources in outer space are covered by the non-appropriation principle is unclear.(2) See Masson-Zwaan and Sundahl (2023), 386; Hobe and Chen (2016), 29; Tronchetti (2015), 790.
As we will see in the following sections, the non-appropriation principle entails that the acquiring or taking ownership of any part of outer space and celestial bodies by any means, is prohibited. In other words, the rule arguably prohibits exclusive ownership of any part of outer space. Yet, there is subsequent uncertainty surrounding the principle’s reach. For example, what does the broad wording of ‘appropriation by use’ or ‘appropriation by any means’ entail? Is it so far reaching that it encompasses ownership of natural resources of celestial bodies? Is it possible to differentiate between the appropriation of celestial bodies themselves and the appropriation of natural resources derived from them? Furthermore, where exactly does the boundary lie between 'appropriation by use' or ‘any other means’, and a type of use that does not constitute appropriation as indicated in the treaty, but may in fact be a freedom guaranteed by the OST Article I?
Key questions in this chapter are:
What is a ‘celestial body’?
What constitutes ‘national appropriation’ under the Outer Space Treaty?
What is the meaning of appropriation ‘by claim of sovereignty, by means of use or occupation, or by any other means’?
What is the relationship between space activities the non-appropriation principle?
Have there been subsequent developments in the interpretations of the non-appropriation principle that may impact space resource activities?