In the mid-2000s, Barre Seid had begun thinking about how to leave a legacy. Riding the personal computer boom, the Chicago-based electronics magnate was on his way to becoming a billionaire. Seid, who considers himself a libertarian, now had the means to pursue a bold project: “attack philanthropy.”

To Seid, that meant looking for ways to place financial bets that had the potential to make epochal change. With little public notice, Seid became one of the most important donors to conservative causes during an era that saw American politics and society shift sharply to the right.

New reporting by ProPublica and The Lever, based on emails and interviews with people who know Seid, sheds light on one of the country’s least-known megadonors, revealing how an intensely private billionaire has secretly used his wealth to try to influence the lives of millions.

Seid has funded climate denialism as well as a national network of state-level think tanks that promote business deregulation and fight Medicaid expansion. He’s also supported […]