Donald Trump Jr.’s investment fund, 1789 Capital, is set to invest a further $300m in Polymarket as part of a funding round worth almost $1bn, taking the prediction market company’s proposed valuation to about $21bn.
The latest investment follows an earlier commitment from 1789 Capital and would significantly increase the fund’s stake in the platform, according to the Wall Street Journal.
1789 Capital first disclosed an investment worth “double-digit millions” in Polymarket in August 2025. At that point, Polymarket was still navigating regulatory uncertainty in the United States and had not yet acquired the CFTC-licensed derivatives exchange that ultimately helped clear its route back into the American market.
The fund is reported to have increased its investment to roughly $200m since then. The latest $300m contribution would form part of a funding round approaching $1bn and value Polymarket at approximately $21bn.
That would represent a sharp rise for a business that some estimates placed in the low hundreds of millions of dollars when 1789 Capital first invested. The growth also gives the deal an added political dimension because Trump Jr. is not only an investor but also sits on Polymarket’s advisory board.
His involvement means the fund has a direct connection to the company’s strategic direction as Polymarket faces legal challenges in several parts of the United States. The Commodity Futures Trading Commission (CFTC) says it has exclusive federal authority over event contracts.
At least 20 states, however, have challenged that position through litigation. They argue that prediction markets covering subjects including sports and elections constitute gambling under state law.
Speaking at a recent event, Trump Jr. backed the industry’s argument that federal regulators should take precedence. He described prediction platforms as already “overseen by federal officials, not state attorneys general” and referred to what he called “robust oversight” at federal level.
Polymarket’s expansion is taking place alongside that of its principal rival, Kalshi. Kalshi completed a $1bn Series F funding round in May, led by Coatue. Sequoia, Andreessen Horowitz, Paradigm, Morgan Stanley and Ark Invest also took part, with the deal valuing Kalshi at $22bn.
Kalshi’s institutional trading volume increased by 800% in the six months before the fundraising. Its annualised volume reached $178bn.
Together, the two companies have attracted about $2bn in new investment within a few months. Their valuations are now separated by only a small margin, underlining the rapid rise of prediction markets and the confidence shown by major investors.
The scale of the funding suggests investors believe regulatory clarity could eventually favour the sector. Both companies, along with their most prominent backers, have publicly embraced that position while legal disputes continue.
Polymarket’s platform serving users in the United States also withdrew both of its NFL player participation filings on 26 August, one day after certifying them with…
