Four Democratic senators are questioning whether Elon Musk‘s X is giving prediction market platform Polymarket preferential treatment, questioning whether its advertising practices could benefit President Donald Trump and his family through the financial interests of his son, Donald Trump Jr.

Senators Question Trump Family’s Financial Connections

In an October 30 letter to X’s leadership, Sens. Catherine Cortez Masto (D-Nev.), Jacky Rosen (D-Nev.), Adam Schiff (D-Calif.) and Richard Blumenthal (D-Conn.) cited screenshots suggesting users cannot report Polymarket advertisements. They contrasted those ads with advertisements from rival Kalshi and Musk’s Starlink, which offer reporting options.

“This seemingly preferential treatment calls into question whether X is attempting to provide an undue competitive advantage to Polymarket and – by extension – the President and his family,” the lawmakers wrote. Their allegations have not established that X deliberately favored Polymarket or that Musk personally intervened.

The concerns center on Trump Jr., who joined Polymarket’s advisory board after his venture capital firm, 1789 Capital, invested in the company in August 2025. The firm later was reported to be leading a $1 billion funding round, potentially valuing Polymarket at $21 billion. Reuters previously reported that Trump Jr. also advises rival Kalshi.

Lawmakers Demand Answers About Advertising Practices

The senators asked X compliance chief Rob DeCampos whether advertisers can purchase exemptions from reporting features and whether Polymarket executives or Trump family representatives sought such arrangements. They demanded answers by November 30.

X, Polymarket and the Trump Organization did not immediately respond to Benzinga’s requests for comment.

The scrutiny comes as X’s partnership with Polymarket, announced in June 2025, integrates prediction-market information into the social media platform.

Prediction Markets Face Growing Regulatory Pressure

Lawmakers also questioned X’s compliance with state gambling restrictions after conflicting federal appeals court decisions on prediction markets.

Kalshi faces mounting legal challenges over sports-related contracts, with states arguing that federal oversight does not override gambling laws. Utah recently filed criminal charges against Kalshi and its founders, allegations the company disputes.

Meanwhile, Reuters reported on October 27 that the Commodity Futures Trading Commission had reopened an investigation into Polymarket’s compliance with a 2022 settlement restricting American participation. The investigation does not establish wrongdoing.

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