I'm managing a Google Analytics implementation on a fairly large e-commerce site. We're a big enough site to have multiple subdomains... So, we have:
Unfortunately, we are seeing a significant amount of self-referral traffic from these sub-domains, and our understanding is that this will dramatically impact all of our session and attribution metrics. Since we're using Universal Analytics, we added all of the domains and subdomains (without the WWWs) to the referral exclusion list in GA. Unfortunately, no dice. We're still getting tons of self referrals.
Additional notes: All of our sites push users over to HTTPS by default. Also, we have a reasonably large number of 301 redirects throughout the site to push people from old URLs to new, or to send them from HTTP to HTTPS, etc.
How can we eliminate the self-referrals?