Can nofollow links hurt my site’s ranking?

Matt's answer:

Today’s question comes from the United Kingdom. Timmy asks, I’m building links, not for SEO, but to try to generate direct traffic. If these links are no-follow, am I safe from getting any Google penalties? Asked another way, can no-follow links hurt my site? No, typically no-follow links cannot hurt your site– so upfront, very quick answer on that point. That said, let me just mention one weird corner case, which is if you are leaving comments on every blog in the world, even if those links might be no-follow, if you are doing it so much that people know you and they’re really annoyed by you and people spam report about you, we might take some manual spam action, for example. So I remember for a long time on Tech Crunch, any time that people showed up, there was this guy, Anon.TC, would show up and make some nonsensical comment. And it was clear that he was just trying to piggyback on the traffic and drive the traffic from people reading the article directly to whatever he was promoting. And so even if those links were no follow, if we see enough mass-scale action that we consider deceptive or manipulative, we do reserve the right to take action. So we carve out a little bit of an exception if we see truly huge-scale abuse. But for the most part, no-follow links are dropped out of our link graph as we’re crawling the web, and so those links that are no-follow should not affect you from an algorithmic point of view. I always give myself just the smallest out in case we find somebody who’s doing a really creative attack or mass abuse or something like that. But in general, no. As long as you’re doing regular, direct-traffic building and you’re not annoying the entire web or something like that, you should be in good shape.

by Matt Cutts - Google's Head of Search Quality Team

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