Following up on previous posts (one, two) about controversy surrounding Friendster's recently-granted patent for social networking technology, Brian Aker says,
Back when I wrote the Zoo system for Slashdot, its social network system, I looked into the sixdegrees patent and commented at the time on it for Slashdot and Livejournal: Link to post. These types of patents are very implementation specific, and while the design for the systems are common enough, there are different methods of achieving the same ends — so social network systems need to be aware of how the patent is spelled out.
Link to Friendster patent.