I was doing a duplicate content search on the web for our site content and found that someone has downloaded/mirrored our entire website and is hosting it on a subdomain of their own main domain. When I check the WHOIS database, no details of the user are available.Why do people do this when it is clearly a copyright infringement - is it an SEO thing?What is the best way of dealing with these individuals?
Website theft - what is the best way of dealing with these individuals?
seo;content;copyright;legal
You should try to contact the domain owner and/or webmaster and/or site author and/or web hoster. But if this doesnt work or if you dont want to wait for answers/actions:Because they seem to copy/update your site one-to-one automatically, you could try some tricks to  mitigate possible negative effects:Make all internal links relative and use the base element, set to your domain. If someone clicks on a link on the duplicate site, they should land on your site.Add a link element with rel value canonical to every page, containing your absolute original URL of that page as href value. You could insert JavaScript to detect the current URL and have some fun if it doesnt match your domain. E.g. hide the content and display a message to the visitors that this site is an illegal copy. Or try an (ugly) redirect to your site.