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I've seen flavors of this question asked but did not see the exact response I was looking for. If I have a site at:  www.site.com And I am creating a mobile version at:  m.site.com  (let's say a responsive design is not feasible at this time) And all the content on m.site.com is duplicative of the content on www.site.com What's the best way to handle that from an SEO perspective?  Should I put a canonical tag on every mobile page pointing back to the www page?  I assume that is better than a 'no index' tag on all pages of the mobile site?