Warren and Curtis seek election-contract safeguards from Kalshi and Polymarket

US senators Elizabeth Warren and John Curtis have asked Kalshi and Polymarket for information on how the companies prevent insider trading, market manipulation and wagers based on material nonpublic information in election-related contracts, according to a letter the senators sent to Kalshi chief executive Tarek Mansour and Polymarket chief executive Shayne Coplan. The letter requests a written response from both companies by Tuesday, ahead of the midterm elections.

According to the letter, the lawmakers flagged "election-related event contracts" as a particular worry, pointing to cases from 2025 and 2026 in which people wagered on their own races through Kalshi. The senators also brought up claims of market manipulation on Polymarket tied to the 2024 presidential contest. Their questions covered earlier efforts at prevention, referrals made to the CFTC, and the safeguards in force now, and they asked for a written reply by Tuesday.

The senators pointed to a case the CFTC described from 2025, in which a candidate put on trades connected to his own run for office. Videos shared on social media brought the activity to light, and Kalshi then issued a penalty and a suspension. In the lawmakers' view, the exchange's own enforcement history illustrates the risks of contracts that reference elections and political candidates, and they said they are not convinced the firms can oversee such markets with real scrutiny and accountability.

Mark Moran, who ran for the Senate in Virginia as a Democrat, discussed his dispute with Kalshi on the Indian Gaming Association's weekly New Normal podcast. He traced it to a $100 wager he placed on his own candidacy. Kalshi first proposed a one-year suspension plus an $800 fine, he said, but after he would not issue a public statement the penalties grew to a five-year ban and a $6,229.30 fine. Moran added that in November 2025 he asked the exchange's political markets team to list his name in a market on prospective candidates, and the listing appeared within a day, which let him purchase the $100 contract on his own campaign.

Moran objected to the company's requirement that he acknowledge its enforcement action in public, calling it an effort to control his account of the case. Kalshi's enforcement action states that its Compliance Department determined Moran made two trades in the market on 27 January 2026 and then promoted the market generally on social media, conduct it said breached Rule 5.17(z). In a call the next day with the Compliance and Legal Departments, Moran conceded the trades were improper and broke exchange rules, yet he declined to settle the matter and later stopped answering Compliance Department correspondence.