David H. Koch, famous billionaire conservative donor, died Friday at the age of 79.

Koch, along with his brother, gained notority for transforming American politics by donating incredible amounts of money to conservative causes.

His brother, Charles, made a statement about the death. However no precise cause was given for Koch’s passing.

“Twenty-seven years ago, David was diagnosed with advanced prostate cancer and given a grim prognosis of a few years to live. David liked to say that a combination of brilliant doctors, state-of-the-art medications and his own stubbornness kept the cancer at bay. We can all be grateful that it did, because he was able to touch so many more lives as a result,” Charles Koch wrote.

David and Charles created Koch Industries, which is one of the biggest ethanol producers in the country. It incorporates brands such as Georgia Pacific plywood and it’s Cordura cloth is used to make military uniforms and equipment.

The brothers were also known extensively for their role in politics and created the Koch political netowrk. It was famous for creating negative advertising that took aim at democrats such as President Obama.

The brothers in 2004 founded the anti-tax, small-government group Americans for Prosperity, which remains 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.”

David Koch was one of four sons born to Mary Koch and oil industry tycoon Fred Koch. David Koch had stepped away from a leadership role in recent years because of declining health, but died with a net worth of $58.7 billion.