Alice and Bill have a nice summary post on Google’s loss of two recent trademark cases arising out of its Adwords ad system.  Quotes:

Both lawsuits have hinged on Google’s signature keyword-advertising system, Adwords, which pairs text ads with related search results. For example, a Nike ad appears after a search for running shoes. Through the system, Google allows marketers to bid for such search-related keywords, including common branded and trademarked terms.

The negative rulings could hamper the company’s advertising practices–at least in Western Europe, where the courts have been favorable to trademark owners. Google derives the lion’s share of its revenue from online advertising.