Kalshi ends Donald Trump Jr.'s adviser role after 1789 Capital backs rival Polymarket

The break with Kalshi

Kalshi said on Thursday, 12 November, that it had mutually agreed with Donald Trump Jr. to end his advisory role. The arrangement began in January 2025, around the time his father started a second term as president. The company tied the decision to the significant investment his firm had made in Polymarket, Kalshi's main rival. The announcement came about a week after Democrats took control of both chambers of Congress. Kalshi's statement said:

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

Kalshi also said both sides understood that advising two competitors in a fast-growing sector had become complicated. A spokesperson for Trump Jr. described the split as mutual.

Trump Jr.'s two roles

Trump Jr. joined the advisory board of Polymarket in August 2025, the same month 1789 Capital announced its first investment in that platform. He works at 1789 Capital as a partner, and the firm returned to Polymarket a year later. Kalshi had taken him on as a paid strategic adviser in January 2025, shortly after his father was sworn in. A person familiar with the matter said Kalshi had initially allowed him to advise its competitor, but that the two parties recently concluded the arrangement no longer made sense.

Money and stakes

Kalshi granted Trump Jr. about $300,000 of equity as part of the deal, and those shares are now estimated to be worth millions. It was not immediately clear whether he would keep them. Kalshi's valuation has risen 20 times to $40bn. Polymarket has been in talks since late summer over a $1bn fundraising at a $21bn valuation, with 1789 Capital set to increase its stake as a lead investor. In August, 1789 Capital added about $300 million to its Polymarket investments, on top of earlier contributions of about $200 million.

Earlier contributions200

Added in August 2026300

Earlier contributions

200 USD millions

Added in August 2026

300 USD millions

Data from the article text

Kalshi (after reported surge)40

Polymarket (in fundraising talks)21

Kalshi (after reported surge)

40 USD billions

Polymarket (in fundraising talks)

21 USD billions

Data from the article text

Regulation and political pressure

Democrats have said they intend to investigate the financial ties between the Trump family and prediction markets. Elizabeth Warren is expected to take over as head of the Senate banking committee in January, with the power to issue subpoenas. In October, Republican senator John Curtis and Warren wrote to Kalshi and Polymarket asking how they prevent insider trading and market manipulation. Prediction markets let traders bet on outcomes ranging from football matches to election results, and they have benefited from a light-touch regulatory environment under the Trump administration. Both companies have denied that their ties to the Trump family shaped how regulators oversaw them. The Commodity Futures Trading Commission has backed Kalshi in lawsuits with states that claim sports betting rules apply, and Trump Jr. echoed that position in a closed-door meeting with Republican state attorneys general in March.

Open questions

It remains unclear whether Trump Jr. will keep his Kalshi shares, and Polymarket's $1bn fundraising was still described as in talks. Decisions starting in May allowed Kalshi to offer trading in stocks, cryptocurrencies and other assets without owning them, and trading clearinghouses sued over them. They contend the agency is breaching statutes meant to shield investors and markets. Democrats are expected to increase oversight of prediction market companies, including who should regulate them and how they police unusual trading and possible insider trading.