Possible Duplicate:Can I exclude spam domains from my search results? There are several sites that have been out for a while that are starting to crawl StackOverflow and related sites.  I can see why they'd want to highjack the popularity of the platform for their own gain, but it contributes a ton of unwanted noise when searching for answers to questions, whether they can be found on StackOverflow or not.Is there a way to filter out a set of known domains that engage in this practice?  Is there a way to do it without including stackoverflow as part of the search query?  The reason why is that I am not necessarily just looking for StackOveflow answers, but from sources across the web.
Is there a way to always filter results from Google based on a set of unwanted domains?
google search;spam prevention