Paid-search giant Google (NASDAQ: GOOG) has been sued by AMR Corp.'s (NYSE: AMR) American Airlines over an advertising dispute, according to the Associated Press. The suit alleges that Google would sell American Airlines-trademarked keywords to rival airlines. In doing so, Google obviously managed to seriously offend the management at American.

It's interesting that Google refused to settle with American before the case went to court. It proves that Google is aware of these practices and feels they can justify them.

I'd assume that Google refused to settle based on a previous legal decision -- this one related to Geico, a segment of Berkshire Hathaway (NYSE: BRK.A). This case was very similar to American's. Geico was angry because other insurance companies had been allowed to purchase advertising under the term "Geico," a trademark of the company. In this case, the judge decided that Google's procedures were actually legal.

Despite the popularity of Google's search engine, one has to wonder if advertisers or publishers are ever going to seriously put their feet down against Google's practices. Google collects more than half of the AdSense program's revenues for itself and remains incredibly secretive, even to its best publishers. As this case displays, Google also has controversial practices with advertising customers -- practices that could come back and haunt this company in the future.

I'd argue that the company's earnings multiple of 40 and powerful growth estimates from analysts don't reflect the potential risks involved in the company's sometimes-deceptive practices.

Disclosure: Kevin Kelly is long Berkshire Hathaway (B).