It's getting a bit tiresome to see these types of lawsuits, but Eric Goldman notes that this appears to be the ninth such lawsuit
against Google, claiming trademark violations for allowing people to buy AdWords on trademarked terms (or suggesting them as keywords). This time the company suing is Rosetta Stone, but the complaint is basically the same. In fact, it uses the same lawyers and apparently the same boilerplate language as some previous lawsuits (wonder if they charge full price for reusing the same text?). The problem is the same, however. It's a general misunderstanding of the purpose of trademark law, which does not give the trademark holder full control over the trademark, but merely is designed as consumer protection to stop confusion among buyers or, possibly, dilution of the trademark. But that does not
prevent the use in competitive advertisements. And, even if it did
the liability would be on the advertising party, and not Google. But Google has the cash, so everyone sues Google.