Read this article from Ronan Shields of The Drum, in which the operation of "Hyphbot" is described. Hyphbot is the designated name of a botnet discovered by Adform, estimated to generate revenues of $500,000/day by consuming 1.5 billion daily ad requests. Adform's CRO, Jay Stevens, called Hyphbot a "call to arms" for the adtech industry.
Adform consulted MMI for peer review prior to the publication of their findings. Read the whitepaper here.