Donald Trump Jr Cut Loose by $40 Billion Kalshi as Rival Investment Sparks Conflict of Interest

Donald Trump Jr has parted ways with prediction market giant Kalshi after his venture capital firm deepened its investment in rival Polymarket. The New York-based company, valued at $40 billion (£30.22 billion), confirmed the decision on Thursday, 12 November, describing the separation as mutual.

The announcement followed months of discussions over Trump Jr's competing business interests. His firm, 1789 Capital, led Polymarket's latest funding round, raising questions about his continued advisory position at Kalshi.

Donald Trump Jr's Polymarket Investment Forces Kalshi to End Advisory Deal

Kalshi said the agreement ended because Trump Jr's investment activities created a conflict of interest, rather than because of political pressure.

'We have mutually agreed to end Don's advisory role after his firm's significant investment in a competitor this past summer,' a company spokesperson told Reuters.

The spokesperson thanked Trump Jr for helping the company reach more customers and said discussions about ending the arrangement began in August.

His relationship with Polymarket was already public by then. In August 2025, the rival platform announced that 1789 Capital had invested in its business and that Trump Jr had joined its advisory board.

The situation became more complicated when 1789 Capital subsequently led Polymarket's latest funding round. Kalshi reportedly contacted Trump Jr during the autumn to discuss the competing business interests.

Although Kalshi denied that political considerations influenced its decision, two people familiar with the matter told Reuters that concerns had also emerged internally about the potential ramifications of the Democrats' midterm election victories.

The party's gains in both chambers of Congress could expose businesses connected to President Donald Trump's family to greater scrutiny.

Democratic Senator Elizabeth Warren has also vowed to crack down on insider trading in prediction markets, while other lawmakers have proposed restrictions on contracts involving sensitive government activities, including military operations.

Neither Trump Jr nor Polymarket immediately responded to Reuters' requests for comment.

Donald Trump Jr Joined Kalshi in January 2025 Before Its Rivalry With Polymarket Intensified

The separation marks a reversal from 13 January 2025, when Kalshi welcomed Trump Jr as a strategic adviser shortly before his father's presidential inauguration.

At the time, co-founder and chief executive Tarek Mansour praised Trump Jr's business experience and influence. The company hoped he would help expand its audience and bring prediction markets into mainstream American life.

Trump Jr publicly endorsed the platform, recalling how his family monitored Kalshi's election forecasts during the 2024 presidential contest.

'I immediately knew I had to contribute to their mission,' he said when announcing his appointment.

The arrangement also carried a financial incentive. According to the Financial Times, Trump Jr received an equity stake in the company reportedly worth approximately $300,000 (£226,665) at the time, as subsequently reported by Reuters.

Kalshi's rapid expansion unfolded alongside regulatory disputes over election-related contracts and growing competition from Polymarket.

By August 2025, Trump Jr had formally joined Polymarket's advisory board, placing him in positions at two competing platforms.

What began as an opportunity for Kalshi to broaden its political and commercial reach ultimately became a relationship the company could no longer maintain.