Right, I made the point that Google has busted link brokers selling links from websites specifically created as their own private networks, when Google found out, they not only de-indexed the link brokers websites, but these links that were pointed at "clients" websites gave Google a good idea of webmasters that actively purchased links from this broker.
So these "incoming links" from this link broker did hurt those webmasters who purchased one way links from said link broker when he was busted.
SearchKing in 2002 was involved in a lawsuit against Google that they lost, they were selling links on high
PR pages out in the open, Google busted them and striped them of all page rank, all those "incoming links" hurt webmasters who purchased them.
Google recently busted link farm directories that were interlinked, see
Bid for Position Directory of Directory Owners for the main perpetrators who were and still are promoting link farm directories, "incoming links" from these networks hurt all who purchased them and all these link farms were de-indexed by Google.
Now, where is your proper response to these historic facts ?