ARS Technica: "Facebook's entire social network model, which allows users to create profiles for and connect with, among other things, persons and businesses, is based on Yahoo!'s patented social networking technology," Yahoo claims in the lawsuit, filed yesterday in US District Court in Northern California. "Prior to adopting Yahoo!'s patented social networking technology in 2008, Facebook was considered one of the worst performing Internet sites for advertising. Facebook's use of that social networking model has reportedly dramatically driven up Facebook's advertising click through rates."