By Anirban Sen
NEW YORK, Nov 12 (Reuters) – Kalshi has ended its advisory contract with Donald Trump Jr, after his venture capital firm 1789 Capital increased its stake in arch-rival Polymarket, according to a spokesperson for the $40 billion prediction markets startup.
“We have mutually agreed to end Don’s advisory role after his firm’s significant investment in a competitor this past summer. We are grateful for his contributions in helping us market Kalshi to more customers,” the spokesperson said, adding that the decision was mutual and the conversations to end the contract started in August since 1789 led Polymarket’s most recent funding round.
Trump Jr was named a “strategic advisor” to Kalshi in January 2025 and was given a stake in the company that the Financial Times reported at the time was worth $300,000.
Prediction markets first rose to prominence in 2024 as they strongly diverged from traditional opinion polls by signaling a Trump victory. Kalshi, at the time, boasted about the accuracy of its own polls, while criticizing other polls and “traditional media” for failing to anticipate Trump’s “decisive victory.”
Now, such platforms face the prospect of heightened scrutiny from Democrats in the US Congress. Senator Elizabeth Warren, for instance, has vowed to crack down on insider trading on prediction markets.
Polymarket and Donald Trump Jr did not immediately respond to a request for comment.
(Reporting by Anirban Sen in New York, additional reporting by Douglas Gillison; Editing by Megan Davies and David Gregorio)

