A lawsuit brought on by Vringo against AOL, Google, IAC Search & Media, Gannett, and Target began with two patent filings by Andrew Kennedy Lang -- now CTO, but formally of Lycos, who sold the rights back in 1998 and then repurchased them recently: Patents 6,314,420 and 6,775,664. The patents are essential to AdSense and AdWords, according to Ed Liston. He links to the patents, but also highlights other issues that Google is facing.