Sites buying (non-no followed) text links as well as sites selling them live in risky times – at least when it comes to Google rankings. Danny Sullivan of Search Engine Land writes:
[Google] confirmed that PageRank scores are being lowered for some sites that sell links.
In addition, Google said that some sites that are selling links may indeed end up being dropped from its search engine or have penalties attached, to prevent them from ranking well.
However, as Danny points, ironically while Google may deem text link selling networks as spam... they still allow them to advertise using Google AdSense AdWords. And Google even has a rule right in their AdWords content policy saying “Advertising is not permitted for the promotion of techniques and services that would violate Google Webmaster Guidelines. This includes cloaking, keyword stuffing, search engine spamming, and doorway pages.”
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