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I run a high-PR (or whatever we're calling it now) website builder. When you sign up, your URL is a subdomain of the main site (like yourname.foo.com). My site is lucky enough to be on the spammers radar, so they frequently create sites to get more back links. A while back, I caught onto this and neutralized their links (even though they had nofollow tags) by only displaying them as plain text instead of anchor tags. Spammers continue to sign up and create sites, even though their links are now text. My question: Are these text links still affecting my SEO negatively? Or do they know something I don't?