Recall https://t.co/ngSLofk0VF ? We're taking action on hundreds of buyers, dozens of sites, & dozens of spammy writers.
— Matt Cutts (@mattcutts) December 20, 2013
Blackhat SEO companies are pitching authors directly, and circumventing the website and blog owners. These are not business transactions from high-up the decision making ladder. Google has been in hot pursuit of link sellers, buyers, networks and brokers that violate it's policies.
The Gawker story mentioned one such network by name--Backlinks.us. The story reveals an email chain that includes examples of other large websites that have utilized the services of Backlinks.us.
SOURCE: Hamilton Nolan, 12/03/13, gawker.com/shady-marketing-firms-are-still-quietly-bribing-blogger-1475562509