<story><title>Stackoverflow abuses nofollow (2011)</title><url>http://www.brianbondy.com/blog/id/104/stackoverflow-amongst-nofollow-web-abuse-sites</url></story><parent_chain></parent_chain><comment><author>kmontrose</author><text>This was dealt with more than a year ago, when we did remove nofollow from trusted posts links&apos; &lt;a href=&quot;http://meta.stackoverflow.com/questions/111279/remove-nofollow-on-links-deemed-reputable&quot; rel=&quot;nofollow&quot;&gt;http://meta.stackoverflow.com/questions/111279/remove-nofoll...&lt;/a&gt;.&lt;p&gt;Would have been dealt with even earlier, but our experiments with it (&lt;a href=&quot;http://meta.stackoverflow.com/a/69032/130213&quot; rel=&quot;nofollow&quot;&gt;http://meta.stackoverflow.com/a/69032/130213&lt;/a&gt;) lead us to believe Google was starting to treat us as a link farm.&lt;p&gt;What we were seeing in our earlier attempt wasn&apos;t pages appearing lower in results (which could reasonably be expected in some cases as a result of the change; and we wouldn&apos;t care, 2nd on a search under an equally good resource is fine by us), but pages being removed entirely; almost universally pages that had newly un-nofollow-ed links to stores, or ad-laden sites (mostly legitimate posts, but some spam that stuck around for a bit before the community deleted it).  So, &quot;classified as link farm&quot; seemed like the most likely problem.  Google naturally won&apos;t tell you why your ranking drops, so it was (and remains) just an educated guess as to what happened.&lt;p&gt;So we stopped, putting it on the &quot;wish we could, but reality doesn&apos;t let us&quot;-list until Google reached out to us (among thousands of others, I&apos;m sure) to change our nofollow practices.  Google didn&apos;t describe any changes in their algorithm, but it seems reasonable to me that there would have been some tweaks around nofollow to accompany a new policy; again just an educated guess.&lt;p&gt;Basically, this is an old post complaining about a long since addressed concern that we had tried to address even earlier but ran into practical problems with.&lt;p&gt;While the exact details of our algorithm are secret by necessity, I will say that we&apos;ve had to consider posts individually to prevent spammers from kiting a single account up to post nofollow-less spam content.  People still try, it&apos;s kind of astounding how much spammers try (I suspect SEO&apos;s opaqueness cuts both ways here), but it doesn&apos;t work (well, you can get &lt;i&gt;one&lt;/i&gt; link in your profile; but there&apos;s less SEO juice to pass and you are hard-capped at one, no matter how long it takes someone to delete your account).&lt;p&gt;Disclaimer: Stack Exchange employee, I was on all the relevant calls but has been a &lt;i&gt;couple years&lt;/i&gt; so grain of salt and all that.</text></comment>
<story><title>Stackoverflow abuses nofollow (2011)</title><url>http://www.brianbondy.com/blog/id/104/stackoverflow-amongst-nofollow-web-abuse-sites</url></story><parent_chain></parent_chain><comment><author>gojomo</author><text>Sites are free to overuse &apos;rel=nofollow&apos;, and search engines are free to selectively ignore it (for either link-discovery or ranking purposes).&lt;p&gt;The strongest point I see made by this author is about SO&apos;s hypocrisy: SO requires attribution to be with a link, and specify that link must not have &apos;rel=nofollow&apos;. Yet their content relies heavily on references to elsewhere which are &lt;i&gt;all&lt;/i&gt; &apos;rel=nofollow&apos;ed.&lt;p&gt;A sense of fair play in attribution, and spirit of mutual assistance between reliable authorities, would suggest allowing at least some well-vetted outlinks to be unencumbered.</text></comment>