David and Charles Koch are the captains of Koch Industries, the largest privately owned company in the United States, with revenues of $100 billion. The brothers also run the Koch family foundations whose stated goal is "advancing liberty and freedom." Among their pet projects, according to documentarian Robert Greenwald's film Koch Brothers Exposed: http://www.kochbrothersexposed.com/ dismantling public education, eviscerating environmental regulation, and spreading disinformation about Social Security with an eye to rolling back the New Deal era safety net.
The Kochs' recent forays into media acquisition, and their increasing power after the Citizens United decision, were the subject of a PBS documentary "Citizen Koch" by Oscar-nominated documentary filmmakers Carl Deal and Tia Lessin, which PBS, a major recipient of Koch funds, refused to air:
http://progressive.org/viewers-unlike-you
'The Kochs are big donors to conservative and libertarian groups, including the Heritage Foundation, the Cato Institute, Americans for Prosperity, and FreedomWorks, and have spent millions on conservative political candidates.