Umm, yeah... Plenty of companies own the rights to use specific words as trademarks
Apple, McDonalds, Nike, Google, Walmart, Microsfoft, etc.
Distinctive trademarks however, have to acquire distinctiveness thorugh secondary meaning - the point where consumers are easily able to recognize the source of the product.
They teach intellectual propertiy in law schools. But you don't have to go to law school to know this stuff. You have access to the internet now. There is no excuse to be ignorant anymore.
Having said that, if the word "Sky" had actually acuired secondary meaning and every other person on the street knew that the word "sky" could refer to a product that was produced by a particular entitity, then BSkyB could have actually won this case.
PeterDuck's comments