(CNBC) -- Billionaire industrialist, donor and political activist David Koch will retire from his roles at Koch Industries and other Koch-affiliated groups due to health reasons, according to an internal memo obtained by CNBC on Tuesday.
Koch, 78, and his older brother, Charles, are the key drivers behind a juggernaut political network that has often favored conservative and libertarian politicians and policies, such as tax cuts. His political legacy includes activism in support of free-market initiatives such as eliminating trade barriers between countries and easing regulations on industry.
David Koch, executive vice president at Koch Industries, will become director emeritus.
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