WASHINGTON (AP) - Billionaire industrialist David H. Koch, who with his older brother Charles was both celebrated and demonized for transforming American politics by pouring their riches into conservative causes, died Friday at 79.
The cause of death was not disclosed, but Koch Industries said Koch, who lived in New York City, had contended for years with various illnesses, including prostate cancer.
A chemical engineer by training, Koch was an executive in the family-run conglomerate, the Libertarian Party's vice-presidential candidate in 1980 and a major benefactor of educational, medical and cultural organizations.
But he and his brother became best known for building a political network dubbed the "Kochtopus" for its far-reaching support of conservative and libertarian causes and candidates.
The brothers in 2004 founded the anti-tax, small-government group Americans for Prosperity, which continues to be one of the most powerful conservative organizations in U.S. politics.
"I was taught from a young age that involvement in the public discourse is a civic duty," David Koch wrote in a 2012 op-ed in the New York Post. "Each of us has a right - indeed, a responsibility, at times - to make his or her views known to the larger community in order to better form it as a whole. While we may not always get what we want, the exchange of ideas betters the nation in the process."
While lionized on the right, the Koch brothers have been vilified by Democrats who see them as a dark and conspiratorial force, the embodiment of fat-cat capitalism and the corrupting role of corporate money in American politics.
The Kochs invested heavily in fighting President Barack Obama's health care overhaul; they fought to bring conservative voices to college campuses; and they developed a nationwide grassroots network pushing conservative causes and candidates at the state and national levels.
The one exception: President Donald Trump. The Kochs refused to endorse Trump in 2016, warning that his protectionist trade policies, among other priorities, weren't sufficiently conservative.
David Koch had stepped away from a leadership role in recent years because of declining health, and his brother became the network's public face.
After battling prostate cancer for 20 years, he told a reporter following the 2012 Republican convention that he was thinking about his legacy.
"I like to engage where my part makes a difference," he told The Weekly Standard. "I have a point of view. When I pass on, I want people to say he did a lot of good things, he made a real difference, he saved a lot of lives in cancer research."
David Koch donated $100 million in 2007 to create a cancer research institute at the Massachusetts Institute of Technology. He also gave millions to Johns Hopkins University in Baltimore, the Memorial Sloan-Kettering Cancer Center in New York, the M.D. Anderson Cancer in Houston and other institutions.
The Lincoln Center theater that houses the New York City Ballet became the David H. Koch Theater in 2008 after he gave $100 million. The Smithsonian's National Museum of Natural History opened a wing in his name dedicated to the story of human evolution after he contributed $15 million.
He said his philanthropy was fueled by a brush with death during a 1991 collision of two airliners at the Los Angeles airport. More than 30 people were killed.
"I felt that the good Lord was sitting on my shoulder and that he helped save my life because he wanted me to do good works and become a good citizen," he told Barbara Walters in 2014.
Koch, who held degrees from MIT, joined Koch Industries in 1970 and served on its board.
Co-founded by his father, Fred, the Wichita, Kansas-based conglomerate has vast holdings in oil refineries, paper mills, fertilizer plants, cattle ranches and other ventures. It is the company behind Stainmaster carpeting, Brawny paper towels and Dixie cups.
The University of Massachusetts Amherst's Political Economy Research Institute ranks Koch Industries one of the top 20 air polluters in the U.S.
David Koch also served as CEO of Koch Chemical Technology Group LLC, a Koch subsidiary. He retired from the company as executive vice president in 2018.
Charles and David Koch, each with an estimated net worth of $50.5 billion, were tied for 11th place in 2019 on the Forbes 500 list of the nation's richest men.
Two other Koch brothers, Frederick and Bill Koch, ended up on the losing end of a power struggle for control of the company's board. They sold their stake in Koch Industries in 1983, later unsuccessfully claiming they were cheated out of more than $1 billion. David and Bill Koch were twins.
David Koch is survived by his wife, Julia Flesher, had three children.
On Friday, Charles Koch said of his younger brother: "The significance of David's generosity is best captured in the words of Adam Smith, who wrote, 'to indulge our benevolent affections, constitutes the perfection of human nature.'"