The following regulations must be followed while registering a .US domain name:
The Name Server restrictions are as follows:
While providing Contact details for .US domain names, you would be asked to specify the Nexus Information which pertains to:
Application Purpose: Whether the domain name being registered is for Business use (Profit/Non-profit), Personal use, etc.
Nexus Category: Whether the person registering the domain name is a resident/citizen of the United States of America, or the domain name is registered for an organization based in the United States, or having an office or facility therein.
The following words/phrases, or combination of any of these seven words/phrases are not allowed in any .US domain name:
shit
piss
fuck
cunt
cocksucker
motherfucker
tits
-
The following categories of names are reserved:
All numbers five digits and higher
All numbers in the format five digits-four digits (zip codes)
All telephone numbers including toll-free numbers
All names with hyphens in the third and fourth character positions (e.g. "pt--xs2h4l4b")