Spider.io used to release quite a few studies on this. One such: http://www.spider.io/blog/2013/03/chameleon-botnet/ http://www.spider.io/blog/2013/03/chameleo

Spider.io used to release quite a few studies on this. One such: http://www.spider.io/blog/2013/03/chameleon-botnet/ http://www.spider.io/blog/2013/03/chameleon-botnet/ But they got bought over by Google recently - Didn't think Google would need to acquire a team around fraud detection and prevention - GOOG pretty much wrote the book on Click Fraud. Personally felt it was a deal done more to prevent the release of such articles that might harm the Online Ad World or GOOG's creds.