Key Takeaways
- Under the 1967 Outer Space Treaty, no country can claim sovereignty over the Moon or any part of it.
- Countries, and private companies authorized and supervised by their governments, may build stations on the Moon, but stations must be open to visits by other states on reasonable notice.
- The Artemis Accords, signed by 76 countries as of September 2026, set out nonbinding principles on resource extraction and safety zones, while broader rules for space resources are still being negotiated at the UN.
American astronauts were the first to walk on the Moon, but does that give the United States any claim to it? And if a country or company builds a base there, can it keep others out?
In this TalksOnLaw Brief, Joel Cohen talks with Frans von der Dunk, Harvey and Susan Perlman Alumni and Othmer Professor of Space Law at the University of Nebraska College of Law, about the legal status of the Moon and the open questions that lunar bases and mining will raise.
A Global Commons
The easy answer, Professor von der Dunk says, is that nobody owns the Moon, or more precisely, the whole community of states owns it together. The Outer Space Treaty of 1967 provides that no state may appropriate any part of the Moon. The treaty did not create an international authority to govern it. Instead, much like the high seas, the Moon is a global commons, open to all states to explore and use as long as they comply with international law.
States, Companies, and Lunar Bases
The freedom of space activities belongs first to states, he explains. Private companies depend on authorization from their governments, which remain responsible and liable for what they do. States may build stations on the Moon, but building one does not mean owning that part of the Moon forever. If another country wanted to inspect a station to verify that no military installations or weapons were present, its representatives could come in, though the host may take reasonable precautions first. The visitor could not occupy the facility. He adds that the 1979 Moon Agreement, which tried to create a resource regime, has not been ratified by the major space powers and can largely be set aside.
Use Without Ownership
You cannot own lunar land, but you are free to use it, he says. Whether continuous use can, in practice, keep others out indefinitely remains an open question. He points to the geostationary orbit, where occupying a slot is treated as time-limited rather than permanent, as a model for thinking about how long a lunar site can be held.
Safety Zones and Customary Law
The treaty does not mention zones, partly out of fear that they could turn into territorial claims. Instead, he explains, the law will develop through state practice: if one country announces a reasonable safety zone and others accept or copy it, that practice can harden into customary international law, while a broad rejection would push the first state to retreat.
What to Know Now
Professor von der Dunk's framework remains the foundation, and the safety-zone dynamic he describes is now unfolding. The Artemis Accords, launched by the United States in 2020, had 76 signatories as of September 2026. They state that extracting space resources does not in itself amount to national appropriation and call for safety zones to avoid harmful interference. Supporters see the Accords as practical implementation of the Outer Space Treaty; critics, including countries that have not signed, such as China and Russia, see rules being set outside the United Nations. A UN working group is drafting principles for space resource activities, and few nations remain parties to the Moon Agreement.
