As if we need any affirmation that linking to “bad neighbourhoods” can cause your rankings in Google to nosedive, but here’s an interesting quote from the Official Google Webmaster Blog ;
Q: I’ve cleaned it up, but will Google penalize me if the hacker linked to any bad neighborhoods?
A: We’ll try not to. We’re pretty good at making sure good sites don’t get penalized by actions of hackers and spammers. To be safe, completely remove any links the hackers may have added.
Bad neighbourhoods, to Google, are typically identified by spammy on-page ‘seo‘ techniques and dubious backlink and interlink profiles. You do not want to link to these neighbourhoods, because who you link to matters.
You see search engine spam sites more often than not link out to other spam sites. Spammers and Crackers, intelligent if somewhat unscrupulous, know that these spam networks (or neighbourhoods) need links from trusted sites to validate their existence. Links from trusted sites transfer trust and votes of relevance (Google Juice, whatever) to the receiving sites, allowing these sites into Google’s index. So, they hack your site, place hidden links in the code, and leave you none the wiser.
Google hates hidden links and spam networks. Rather than let your site “heat” up and validate a spam neighbourhood so that it can start receiving visitors from Google, it might just remove your site from the index, by classing your site as part of that bad neighbourhood.
Determining if a site is in a bad neighbourhood can take some experience, but using this quirky tool, you can actually spot some of the most obvious infractions, like hidden links in articles. I ran the test on the Hobo site and was surprised to see one of my friends had indeed been the victim of a hidden link injection to casino sites and loan brokers. :(
Have you been hacked? If you’ve spotted it before you’ve seen your rankings bomb, there are measures you can take (apart from deleting the offensive links immediately!). This has happened to me before, and as long as you take action immediately, you’ll probably be OK. Check out this site about WordPress security for more on how to secure your blog from hackers. I’ve not implemented all the measures I would like to yet, but vigilance is still a good form of security.
If you’ve been penalised by Google (ie removed from the search engine index) because you now link to a bad neighbourhood, you should read Google’s official advice if you’ve been hacked.
My theory is that Google will crawl your site a number of times to check if you still have these links to spam sites. If you remove them, no problem. If they survive multiple crawls, your site may suffer some kind of Google ranking penalty based on a violation of Google guidelines for inclusion or as part of bad neighbourhood identification.
UPDATE – Google now helps you with notifications you’re hacked, and how – http://googlewebmastercentral.blogspot.com/2009/10/fetch-as-googlebot-and-malware-details.html
In 2013 – Google also clearly punishes you for bad neighbourhoods linking you to your site!