Donors say they’re not overly concerned about the day when Charles Koch will no longer lead their movement.

Looking to Future
“He’s a major figure, but the donors within the organization are not wimps and they are very dedicated to the mission,” said Chris Rufer, a libertarian-leaning donor who owns the Morning Star Company, a major tomato processor in California’s Central Valley.

Charles’s son, Chase, is likely to eventually play a top leadership role in the network and has already made appearances at the donor conferences. “Chase is already very involved,” Levin said.

Brian Hooks, president of the Charles Koch Foundation and Charles Koch Institute, has also played a prominent role and often joins his boss on stage at donor conferences. Mark Holden, chairman of Freedom Partners Chamber of Commerce, the hub group for top Koch donors, is also viewed as a senior official.

Hooks and Holden weren’t available for interviews, said James Davis, a spokesman for the network. The men serve as co-chairmen of the semi-annual donor gatherings that are formally called the Seminar Network.

‘Built to Last’
“There will only ever be one Charles Koch,” Davis said in a statement. “Fortunately, he’s still going strong. But you better believe he’s built this network to last, just like he’s done with his business.”

The massive wealth held by the Koch brothers is the top reason they may have a legacy of influence on American politics for decades to come.

Each brother has a net worth of about $47 billion in the Bloomberg Billionaires Index, tied at 12th among the world’s richest people. David Koch, who resides on New York’s Upper East Side, is the city’s wealthiest person. Charles Koch, not surprisingly, holds that title in his home of Wichita, Kansas.

The brothers derived most of their wealth from a 42 percent stake in Wichita-based Koch Industries, which has an annual revenue of about $100 billion and is the nation’s second-largest closely held company.

The Charles Koch Foundation, which has grown significantly in recent years, listed assets of almost $700 million at the end of 2016, its most recent Internal Revenue Service filing shows. It gave to dozens of universities and other entities, including libertarian think tanks and groups aligned with the views of its namesake.