In 1994 a competitor to Interop trademarked the generic
word "shownet" as a purely hostile move, forcing Interop
to stop using it because it had not previously been
trademarked and the theory was that it would take to much
time and money to fight.
Whose theory was that? At least in the United States, that makes little
sense. In the U.S., you must show that you have been consistently using a
trademark and identifying it with your product or service in order to claim
proprietary status for it, and if you have not been actively using and
protecting it, or if someone was actively using it before you did, your
trademark is unlikely to stand. Maybe Interop should have fought it.
Trademarks are not like patents or copyrights. You must actively use and
protect a trademark, or it can lose its special status. And you can only
register it _after_ you have established it as a trademark, not before (in
the U.S.--in Europe, you can register before you use it, which is kind of
bizarre and much more restrictive).
Thus, it is now called "InteropNet" and yes, it's heavily
trademarked.
It's either a trademark or it's not. There are no degrees of trademark
(other than registration).