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In this situation I have SiteA, and SiteB on completely separate domains.  SiteA is the marketing front for the company and SiteB is an app that company owns.  SiteB receives a fair amount of backlinks as it has the login page of the application where customers link to a branded version for their members to login. Additionally none of that domain is indexable including the login page. SiteB's domain can't be changed to be a subdomain of SiteA as it isn't technically feasible. Initially I was reluctant to use canonical because as it isn't really duplicate content.  Is there a method for forwarding any link-juice from SiteB to SiteA without the use of a redirect and would canonical be appropriate in this case?  Additionally would SiteB's not being indexed negate any link benefit? Edit: Typo