How does Google track that?
They know they are paid links because people sell them on the internet. Google probably has 99% of the internet cached, so if a site makes references to selling links on their sites or even on other sites they could be tagged as link-sellers and have their outbound links devalued.
I suggest you never talk about selling text links on any of your sites in public.
Everyone sells links. I can't imagine that would hurt you.
Thanks for explaining that.
..except a few sites get removed from the google index when they get caught!
Perhaps so, but isn't that the reason for the internet? Advertising? Google's business is seaching sites and letting the public know what is out there on the internet. Purchasing a link from a well-known site for your site could only help your ranking, not hurt it. Now, I think that these link farms are a different story.
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