Imagine one day you wake up and find your website is no longer indexed by Google -- that means not a single visitor is coming to your website from Google organic search results! Further, imagine you didn't violate any of Google's rules. That's exactly what happened to one of our more valuable websites.
How? Our website is hosted with ValueWeb who will not assign or sell entire C blocks of IP addresses. Hosting companies like this one typically have so many customers, that they can not pre-emptively screen them for spammers. They can only react once a customer reveals itself as a spammer, but by then, it's too late. If one of Valueweb's customers is caught sending spam from, or spamvertising their ValueWeb-hosted site via an outside service, the spam trackers like SORBS may blacklist the entire netblock, falsely implicating many innocent websites.
Next, Google delists all the websites blacklisted by SORBS and there you are -- presumed guilty, tried and convicted on the spot. In our case, the website in question is a non-commercial healthcare website without any commercial activity. It doesn't send email, doesn't sell products or display any advertising.
How serious is a Google ban? My research at WebmasterWorld revealed that others in this situation had indexing restored anywhere from 3 months to 2.5 years later. That could kill a project or even a company.
To be fair to ValueWeb, they responded quickly with assistance requesting delisting from Sorbs. But we'd be foolish to leave our websites in this precarious position where search engine traffic can disappear capriciously at any moment. The lesson? Don't host any website you want indexed by search engines without a dedicated C block. The risk of being punished severely for having bad neighbors is too great. Our core business websites are at Verio in their Sterling, Virginia facility and soon all our other websites will be hosted there too.
The great irony here? SORBS is running AdSense ads on their website, which means that when they capriciously ban an entire netblock, both SORBS and Google stand to make money when innocent webmasters in droves visit the SORBS site to try to figure out what happened!
