I know Google takes the duplicate content thing very seriously, but what does Google do if they find duplicate content?

Google bans the site?

It decrease the page rank of both sites?

Nope and nope.

Does affect SERPs though. One of the two (the 'infringing' site) gets pushed way down in results. I've had it happen to me where a development version of a live site got spidered and jumped to the top of the listings, and the actual site was pushed back to page 50.

They might even come round and spank your backside

Google bans the site for using black SEO techniques but not for duplicate content. It is not a SEO technique at all. Fot duplicate content google will list your duplicate page further down in search engine results pages (somewhere around page 100 of the google search results). Yes, it is almost as bad as being banned

If all the contents of a blog is copied from other source then it will not indexed or show the results of this blog to SE.. It means the blog which have copied things from other source will not get visitors from Google SE.

If all the contents of a blog is copied from other source then it will not indexed or show the results of this blog to SE.. It means the blog which have copied things from other source will not get visitors from Google SE.

I've heard some real dumb things in my time and this one is up there with the best, lets take topix.com for a start, no visitors? No search engines crawling it and indexing it? Feedzilla? Yahoo news?

Originally Posted by smoseley

Does affect SERPs though. One of the two (the 'infringing' site) gets pushed way down in results. I've had it happen to me where a development version of a live site got spidered and jumped to the top of the listings, and the actual site was pushed back to page 50.

It may NOT be the "infringing" page. Search engines neither know nor care which was "original", they show one and filter the rest.