Slate's Explainer knows what you're asking, even if you don't. On Thursday, the column broke down the legal ins and outs of moon landings. Apparently, anyone can drop anchor on the moon: The trick is getting there. According to the Outer Space Treaty of 1967, you need a license to launch.
In the United States, that license comes from the FAA. Brazil, Israel, Russia and other countries with "emerging commercial space sectors" have FAA-analogs that sign off on launches.
As the Explainer points out,
By controlling what and who launches into space, a government can attempt to regulate what happens there. But once you're cleared to launch, you don't need special permission to land on the moon. There aren't any specific guidelines beyond what's in the 1967 treaty as to what happens on the lunar surface.
So what if spacecraft are one day built or launched from orbiting "dry docks?" I know, it sounds very sci-fi, but is it really such a wild proposition?
Any explainers out there want to take this on?