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and Discussion ---- It is easy for competitors to hurt
established sites (negative SEO)  aakk9999 - 10:20 pm on Dec 12,
2013 (gmt 0)  They look for patterns. If your site matches a
pattern of link buying or selling site, it will be probably
labelled as such.  So in the above example, if a link purchase
is one off, and the seller sells one link only to you (does not
sell links to others), you could almost certainly get away with
it. But if this seller sells links to many sites, or you are
buying links from many sites, this shows the footprint.
Unfortunately, some sites may show footprint even when they are
not buying or selling links - they are collateral damage because
otherwise Google cannot scale.  To try to draw some parallels:
I worked with ePOS (point of sale) and this was the way Loss
Prevention in stores/shops worked. The averages and an
acceptable deviation from these average were calculated for
various metrics. And if a checkout operator