US CODE: Title 15, Chapter 1, Section 2.
[antitrust at usdoj.gov removed from cc's]
>So I count one place: ARIN.
Actually, technically speaking, there are two. ARIN and the IANA.
>There could have been others, but they have all agreed among
>themselves to carve the world up into exclusive zones in which each
>will have the sole and exclusive right to allocate address blocks.
"Agreed among themselves"? Please see RFC 1466 and who its authors are.
>Perhaps we just ought to drop the geographic limitations and let the
>three registries allocate anywhere in the world.
This has been discussed in the past in numerous venues, however the major
sticking point is coming up with a way that insures the competitive
registries do not ease allocation requirements in order to obtain additional
customers without creating a huge bureaucracy of auditors. If you come up
with a way, I'm sure all the registries (myself in particular) will be very
interested in hearing about it.