NASA wants to exploit lunar resources in partnership with private companies, after having achieved successful joint ventures in Earth orbit. However, there are legal concerns: lunar land is international territory and therefore not subject to ordinary property ownership. The United States has not acceded to the applicable sections of the Outer Space Treaty for, among other things, how they regulate resource exploitation issues. (Link to a PDF with relevant legal texts >>>)
One American company has now initiated administrative proceedings in the United States to find out how moon colonies are to be regulated. The New Scientist magazine has looked into the matter; read more here >>>