Dave, most spammers are blatantly posting the same links all over the web, that is what Google is looking for, high percentages of reciprocal links in your total link profile or thousands of the same anchor text links (showing that they were placed via automated systems-directory submission services or software/posting agent scripts), these are signs of abuse and search engine spamming.

A few natural reciprocal links will not make you a target for the Google web spam team.

These tactics (buying or selling text links without using no-follow tags or blatant spamming) will get your websites de-indexed in the end.

The reason Google can catch folks for selling links is the fact that they can put 2 + 2 together, they can see the link buyers other paid links pointing to their sites with similar anchor text while the link seller in many cases does not know that their buyer is already known by Google.

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