Newly proposed projects of large satellite constellations are challenging the established business models of the satellite industry. Targeting the Low Earth Orbit (LEO), already the most populated orbit for space applications, these constellations pose an increasing risk regarding the sustainable use of outer space. According to the Inter- Agency Space Debris Coordination Committee (IADC), presenting at the Scientific and Technical Subcommittee of the UN COPUOS in 2018, the implementation level of the IADC Space Debris Mitigation Guidelines in LEO is considered as “insufficient and no apparent trend towards a better implementation is observed", when compared with GEO. In parallel, 11 private entities such as OneWeb, Telesat and SpaceX have applied for approval from the U.S. Federal Communications Commission (FCC) to initiate large satellite constellation projects.
Before the launch of these massive constellations, several legal issues have been identified from the perspectives of international obligations related to liability and registration. Taking them into consideration, as well as the IADC recommendations, the present article reviews one of the most fundamental principles in space law, the principle of non-appropriation, to clarify its applicability to the exclusive use of specific LEO orbits by large satellite constellations. After this clarification, the paper concludes with proposals for possible solutions.