Artificial and Unnatural Linking – Conducting A Backlink Risk Assessment
Google's policy that linking should be for editorial purposes only, and not to improve your search engine rankings has been pretty consistent for nearly a decade. There have always been gray areas, that have been open to interpretation and debate. Sometimes tactics that were perfectly fine and considered acceptable, will be abused, and be frowned upon by Google. These edge tactics can put you on the receiving end of an "Unnatural Links" warning letter in your inbox, followed by dramatic decrease in traffic.