Don Jr. has stakes in Kalshi and Polymarket. Trump's one-man CFTC is suing states that try to regulate them.

Donald Trump Jr. became a strategic adviser to Kalshi in January 2025 with an equity stake then valued around $300,000; Kalshi was later valued at $22 billion. In August 2025, 1789 Capital, where he is a partner, invested in rival Polymarket and he joined its advisory board. 1789 later led a Polymarket funding round, bringing its reported stake to about $500 million.

The Commodity Futures Trading Commission, which oversees these event-betting markets, is designed to have five bipartisan commissioners. Since Chairman Michael Selig, a former crypto-industry lawyer, was sworn in in December 2025, he has been its only member. States have tried to treat sports and event contracts as gambling. Rather than regulate the markets more closely, the CFTC has sued states that do: Arizona, Connecticut and Illinois in April 2026, then Wisconsin, Rhode Island and New York, among others. In August it ordered Kalshi to keep operating in New York after that state sued.

Sludge reported that Trump Jr. addressed Republican state attorneys general about prediction-market regulation in March 2026.