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Hello Carsten, I am not a developer, but hopefully I can be of some assistance. If not, we'll leave the question open to see if anyone else can be more specific for you. First, I came across a good list of eCommerce sites using Isotope: http://isotope.metafizzy.co/ . If you scroll down to "Isotope in use" you'll see examples from Anthropologie, Rimmel London, Lexus, Biodroid, etc... Perhaps looking at how they handle things will help. For example, it looks like Anthropologie uses unique identifying URL for each product that is its own .jps file (e.g. 4130265414412.jsp), or is meant to appear that way. A lot of AJAX sites will use a hashbang (#!) to enable crawling of dynamically created content on the same URL each time. Here is more information about that. The solution you provided above sounds good, but I'd want to see it in action first. Be sure to view the page as Googlebot, and to see how it looks in Google's Cache Preview in the SERPs to make sure they are treating it the way you want them to. Good luck with this, and please let us know how it turns out so we can be more informed on the issue in the future.