I run a mid-size eCommerce business and we just received via certified mail a patent infringement notice from Kelora Systems, LLC regarding US Patent No. 6,275,821 entitled "Method and System for Executing a Guided Parametric Search".<p>The patent is for a “search method” where instead of a hierarchical approach, the application uses family groupings to narrow products (they call it guided parametric search). A hierarchical approach would be one where in order to get to Small Red Widgets I would have to first go to Widgets, then to Red Widgets, then to Small Red Widgets. If you wanted to get to Small Blue Widgets, I would have to go back to the top of the hierarchical tree and then select Blue and then Small to get my Small Blue Widgets. The issue with this being you may not know how your end user may prioritize those things. They may want to see all the Small Widgets and don’t care about the color, but in this hierarchical approach, that isn’t possible as its a branch past the color selection.<p>This is something just about every major eCommerce site does.<p>Doing some research I see we are not alone - http://www.google.com/search?aq=f&sourceid=chrome&ie=UTF-8&q=kelora+patent+troll<p>Essentially they have stated that we can either pay a $150,000 licensing fee within 30 days or they will file a formal complaint and pursue 'legal remedies'. (A copy of the complaint was included)<p>eBay, Microsoft, Target, Office Max, Shopzilla and lots of other major companies have already been targeted. - http://www.docstoc.com/docs/60405793/Kelora-v-Target-Officemax-Shopko-Briggs-and-Stratton-et-al<p>eBay has also counter-sued, however I am not sure how that effects how we can respond to this letter (if at all) - http://dockets.justia.com/docket/california/candce/5:2010cv05106/234117/<p>Some, such as ShopZilla and Footlocker have settled: http://www.prweb.com/releases/Kelora-Systems/Step-Search/prweb5094424.htm<p>My gut is that we need to bite the bullet and pony up to get our lawyers involved immediately, however they are not by any means cheap and would like to be as efficient as possible when dealing with them.<p>Very curious to any insight or advice that can be offered, particularly from someone who has dealt with this in the past.