This is the United States view on asteroids, but there is a 1967 United Nations Outer Space Treaty that may say otherwise.
"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," states Article 2 of the treaty.
"The UN treaty in essence forbids private ownership of celestial property. According to the treaty, you could not arrive on the Moon or an asteroid and claim it for ownership, at least as a country," according to an attorney Michael Gold for Bigelow Aerospace."
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