Most if not all huge brands and co-orporations do this. They cybersquat - meaning they buy all their branded names under all the TLDs available. Accrording to Melbourne IT, approximately 80,000 trademarks were registered under the .xxx tld to protect their own brands before the tld actually launched. With brand protection being key, most companies have a policy of registering their names in all the available TLDs (.com, .net, .org, etc..).
Some say, companies shouldn't even be allowed to register these kind of 'defensive' registrations and should be cancelled if the domain is not use at all.
In the beginning, when news broke that .xxx tld was going to be live, the ICM Registry said it would only sell the tld to official adult entertainment companies, but the report has also stated that ICM CEO Stuart Lawley could also make over $200 Million US Dollars from defensive registration by companies proecting their brand.
What's your take on this issue?

