Nofollow Links in Yahoo and Google Reports

Most bloggers and webmasters with any kind of an eye for SEO have known about the rel=”nofollow” attribute for some time. Often referred to by the colorful nickname “link condom,” it’s a way of tagging a link with zero trust. Search engines will take it as a signal not to pass value (a.k.a. “link juice”) through your link or negatively impact your site for linking to the destination. This is especially useful for automated link processing in such high-risk content areas as blog comments, forum posts, and wikis.

Given how nofollow links are supposed to work, then, you wouldn’t expect to see such links showing up in backlink reports. The weird thing is that Yahoo and Google are doing just that. A quick look at Project Paradox’s inlinks on Yahoo Site Explorer reveals more than a handful of them. Comments I made on Slashdot and several blogs show up in the first two pages of results. And while I can’t link you to it, I see the same sort of links showing up in my External Links Report on Google Webmaster Tools.

My first instinct is to question the freshness of the index. Perhaps some of these links weren’t previously tagged as nofollow but got changed since they were last crawled. Considering the comments from Slashdot, however, this simply isn’t the case; user links on Slashdot have always been tagged with nofollow.

How, then, are we to interpret this? It’s definitely great if you want to see more of the links coming into your site, but it’s confusing as hell from an SEO perspective. Are the two biggest search engines weighing these in their linking algorithm, or simply reporting them in its backlink reports?

By all reports, neither Google nor Yahoo pass any link juice through nofollow links. They do, however, follow such links (counterintuitive as that may seem), spider their destinations, and record them as backlinks. To us users, then, it appears as if they’re handled in exactly the same way as ordinary links. I guess we’ll just have to take it on faith that such links don’t count for anything in the ranking algorithms.