1789 Capital, the venture firm co-founded by Donald Trump Jr., is leading a $1 billion funding round in Polymarket, the Wall Street Journal reported Monday, citing a source familiar with the matter.

1789 is contributing about $300 million, on top of roughly $200 million the firm had already invested, the Wall Street Journal reported. The new raise values the prediction market at $21 billion post-money, Bloomberg reported, lifting the platform’s valuation 40% from roughly $15 billion in a matter of months. Polymarket’s last round closed in April.

This story is an excerpt from the Unchained Daily newsletter.

Polymarket was worth roughly $9 billion less than a year ago. The step-up also narrows a gap that had opened against Kalshi, which raised at $22 billion in May and has since been in talks at roughly $40 billion.

The Trump family’s position in the sector has widened alongside it. Trump Jr. became an adviser to Kalshi in 2025 and received shares worth more than $300,000, and separately advises Polymarket. Michael Selig, President Trump’s appointee to run the CFTC, which regulates prediction markets, has backed the platforms, suing states attempting to regulate them. In May, the president wrote on Truth Social that prediction markets would thrive under his leadership.

Intercontinental Exchange, the parent of the New York Stock Exchange, has committed close to $2 billion across a $1 billion direct investment in October 2025 and a $600 million follow-on in March, making it the platform’s largest backer. The capital arrives after a stretch in which Polymarket fell behind Kalshi on volume and product rollout. Both platforms still face an unresolved jurisdictional fight with states that claim authority over event contracts.

Related Listen: DEX in the City: The CFTC’s Kalshi Rescue and the Limits of Emergency Power