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Hi Sylvain OK, if it is a 302 then no authority will be passed. A 302 redirect is an indicator that the redirection is temporary and therefore will change. Until the redirection is changed to a 301 (permanent) then no authority will be passed over from the backlink. There is more info on redirection here: http://moz.com/learn/seo/redirection Do you have access to the abonnes.hospimedia.fr sub-domain so you can update the redirection to be a 301? Peter

That's the gist of it, unfortunately.  Cyrus posted in this blog entry a Tweet from Duane Forrester of Bing saying over time, they learn that 302 redirects encountered repeatedly are more permanent and begin to treat them like 301 redirects.  I would imagine Google does something similar because it makes sense to do, and would improve search results overall, but I have no evidence to back that up.