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Hi Patrick, On the 27th of September, there were two major updates by Google - an EMD update and a subsequent Panda update. Seeing as you don't EMD, it's possible that it was the Panda update that seems to have hit you. Can I assume that the pages that dropped from rankings were shopping results pages, or pages with pagination? Whereas pages that remain are static pages? The Panda updates address duplicate pages and pages with pagination, so I can imagine that a site like yours probably has a fair amount of what search engines would consider duplicate content. Do you get duplicate content errors in your SEOmoz crawl diagnostics? If that is what you're seeing, then I would recommend canonicalising your pagination pages. http://www.seomoz.org/learn-seo/canonicalization The above is just an idea, and given that I don't think it's a penguin penality (penalises backlinks) overwise your above mentioned fixes should have made some noticeable difference, it will be worth looking into Panda. Best, Matt