The Forbes website has recently been notified by Google as having “possibly artificial or unnatural links…pointing to other sites.”
The act of Selling Links is a black hat SEO practice looked down upon by Google. The purchaser of those links gets to buy “Link Juice,” – the increased probability of getting more clicks from users, generating increased ranking in Google search results by having a presence on an established site.
Forbes admits to selling links through a partner for some time in the past, though they have begun making significant changes and removing those links in late 2010. Some of those changes include a revamped site architecture, and no purchased or “artificial or unnatural” links on their pages.
Source: SE Round Table