Billionaire businessman and the 11th richest man in the world, David Koch has died, according to reports.
American billionaire David Koch, a major donor to the Republican party, has died aged 79. He had been suffering from cancer, BBC reports.
The former majority owner of Koch Industries was ranked by Forbes below brother Charles as the 11th richest person in the world.
Together they had a huge influence on the conservative movement and bankrolled causes pushing for small government and a free economy.
But this has made them both polarising figures.
They gave a lot of money to Mitt Romney's failed presidential campaign but fell out with President Donald Trump over his tough immigration policy and tariffs.
In 2018 Koch stepped down from Koch Industries - which refines crude oil, produces fertiliser, and manufactures household products - citing his declining health.
He had been a major donor to the arts, especially ballet, and donated to New York's Lincoln Center and Memorial Sloan Kettering Cancer Center hospital.
He ran for vice-president as a Libertarian in 1980, calling for the abolishment of many federal government agencies.
According to Forbes, he is estimated to be worth $42.4bn (£34.7bn).
The news of his death was confirmed in a statement from Charles Koch, who said that his brother was first diagnosed with prostate cancer 27 years ago and given only 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," Charles Koch wrote, adding that in those years he married his wife Julia Flesher and had three children.
He also described David as having a "giant personality and passion for life" and noted his "institution changing philanthropic commitments to hospitals, cancer research, education and the arts".