After seeing 100s of sites, talked to dozens of webmasters, did numerous testing and wrote some major SEO companies. I am pretty confident to say, there is no such thing as a FRED Update it is simply a major Update of the well known Panda Algo. This is basically confirmed by Sistrix, one of their social media guys wrote me, that they are seeing many sites formerly affected py Panda are now beeing hit by Fred. Here are the correlations I found: - Keyword Density - Ads especially Above the fold - Ratio of Thin Content sites - Bounce Rate - Page loading time - Spammy links The links which seem to be effected, are mainly Social Bookmarks, Forum span links and SAPE footer and header links. There seem to be no correlation with PBN-Links or Links from Forum threads. Forum Profil links seem to be completely devalued and no measurable effect at all. The good news is, they Algo seems to work realtime and it sometimes shows, immediate recovery. The best tut how to recover is, from my experience this one: http://blog.searchmetrics.com/us/20...initely-get-hit-by-a-panda-algorithm-penalty/ The tools I recommed in dealing with it are bascially: - Seobility Site Crawler (for detecting weaknesses of the website) and - Seobook Keyword Density Checker http://tools.seobook.com/general/keyword-density/ - G Analytics for bounce rates and non-performing content - as well as the SEMRush Dashboard, free Account link audit tool for identifying spammy links I don't have any affiliation with any of these companies and this stuff is all free.