Prediction market platform Kalshi has ended its advisory relationship with Donald Trump Jr. after his venture capital firm took a leading role in a major funding round for rival Polymarket, Reuters reported on Thursday.

A Kalshi spokesperson told Reuters that talks about ending Trump Jr.'s advisory role began in August, after his venture capital firm, 1789 Capital, took the lead on Polymarket's $1 billion funding round. The round values Polymarket at $21 billion, with 1789 Capital set to contribute roughly $300 million of the total.

“We have mutually agreed to end Don's advisory role after his firm's significant investment in a competitor this past summer,” the spokesperson said.

Trump Jr., the son of US President Donald Trump, joined Kalshi as a strategic adviser in January 2025 and received an equity stake that was reportedly worth $300,000 at the time, according to the Financial Times.

Kalshi's spokesperson said the decision was mutual and that political considerations played no role in it. However, two people familiar with the matter told Reuters that some within the company had raised internal concerns about what the Democrats' midterm sweep of both chambers of Congress could mean for Kalshi's business.

Prediction markets allow users to trade contracts tied to the outcomes of real-world events, with prices reflecting the perceived probability of each result. Kalshi operates such an exchange under the oversight of the Commodity Futures Trading Commission (CFTC), offering contracts on elections, economic data releases and other events. Polymarket is a crypto-based prediction market platform that offers comparable event contracts and drew wide attention during the 2024 US presidential election. The two companies compete directly for users in a sector whose financial stakes have grown considerably, to judge by the round's $1 billion size and the $21 billion valuation it places on Polymarket.

Attention now turns to two open threads: how Kalshi's election-linked business develops after the midterm results some of its employees flagged as a concern, and how Polymarket deploys the $1 billion in backing now coming together around 1789 Capital's roughly $300 million commitment.

Source: Cointelegraph