David Koch is leaving both Koch Industries and his role as chairman of the Americans for Prosperity Foundation, the charity arm of the sprawling Koch network. | Dia Dipasupil/Getty Images for Lincoln Center David Koch leaving business, political network

Billionaire David Koch is retiring from his family’s business and political network, citing health issues.

Koch’s departure was announced in a letter sent by his brother, Charles Koch, to Koch Industries employees on Tuesday. He first announced to the company that he had been experiencing health problems in October 2016.


“David will be retiring from his responsibilities at Koch and other organizations,” Charles Koch wrote in the letter. “We are deeply saddened by this, as we miss David’s insightful questions and his many contributions to Koch Industries.”

David Koch is leaving both Koch Industries and his role as chairman of the Americans for Prosperity Foundation, the charity arm of the sprawling Koch network.

Charles Koch has served as the face of the network’s political activity in recent years.

