In some cases, a company will ignore names like this if they don't harm them. Look at all the wii domains registered with little word of C&D's. Sometimes the publicity alone is worth allowing them, particularly if the name is used to promote the product or technology. However, if someone registered a bluray variant and pointed to the competing technology, that might put them on the legal radar. With something that big, sometimes you just have to pick your fights based on your legal budget and the harm they do or don't do. Just because there is no action doesn't mean it's legal or morally right. It may just not be know or worth the trouble to them. The buyer could end up being an authorized dealer or partner who is allowed fair use of the term. If I spent that kind of money, I surely wouldn't risk it by doing something stupid.