Venture capitalist Peter Thiel has written his biggest political check in years, donating $3 million to a California business group leading the fight against a proposed billionaire wealth tax. The move positions the Palantir co-founder as one of the earliest and most prominent financiers of an emerging campaign to stop the 2026 Billionaire Tax Act before it reaches voters. Thiel made the $3 million contribution on December 29 to the California Business Roundtable,