This seems to be a problem (among others in this story) which Google could answer to.
One thought that comes to mind is that no site's reputation should automatically survive transfer of ownership of that site.
If a site's new owners share the mission and custodial mission of the original owners, fine. If not, the site starts from zilch. Or better: negative assertion value given the long history of link-farming and its exceedingly well-understood common weal costs.
