Adversarial advertising; also see 10 million people saw Russian ads on Facebook around the 2016 presidential election (Recode)
"The conclusions of investigators fit those of several independent researchers, who say that the Russian disinformation campaign exploited the core advertising and tracking technologies that Silicon Valley has honed over a decade to serve corporate America — and that are widely available, with few if any restrictions, to political actors in the United States and abroad.Russians took a page from corporate America by using Facebook tool to ID and influence voters - The Washington Post
“These are the same methods and sophisticated tools that the pharmaceutical companies were using, that big oil companies were using,” said Philip N. Howard of Oxford University’s Computational Propaganda Project. “This was regular ad technology that regular advertisers use.”
The revelation about the use of Facebook’s Custom Audiences tool, which has not been previously reported, adds to an emerging picture of a Russian effort to shape the U.S. election and sow division using tools built by American technology companies."