Warren and Curtis demand insider trading data from Kalshi and Polymarket

A letter arrived at the offices of two prediction market executives on the eve of the midterm elections. Senators Elizabeth Warren and John Curtis — one Democrat, one Republican — signed it together, which is the part that should concentrate the mind of anyone reading the public filings on this.

The letter went to Kalshi CEO Tarek Mansour and Polymarket CEO Shayne Coplan. Its request was specific: written documentation of past prevention measures, active safeguards, and any instances of election-related insider trading that had been referred to the CFTC. The deadline was election day itself.

The senators' stated concern is market manipulation on election contracts. Their evidence is not theoretical. The letter references a 2025 incident the CFTC itself described, in which a candidate traded on his own candidacy, a fact that surfaced through social media before Kalshi acted. It also references the case of Mark Moran, a former Virginia Senate candidate who says he asked Kalshi's political markets team to list him as a tradeable candidate, received the listing within a day, and then purchased a contract on his own campaign using an account verified with his own driver's license. Kalshi later offered him a one-year suspension and an eight-hundred-dollar fine. When he declined to issue a public statement, the penalty rose to a five-year ban and a fine of six thousand, two hundred and twenty-nine dollars.

The mechanics of what Moran describes are what make the letter legally significant, separate from the political theater of a bipartisan signature. He was a named market participant trading on material nonpublic information — specifically, his own intention to run. The platform listed him on request and then permitted him to trade. Whether that sequence satisfies the elements of insider trading under the CEA depends on whether election contracts qualify as commodity interests, which is precisely the jurisdictional question every current preemption case is fighting over.

The CFTC's position on insider trading in political event contracts has not been stated with the specificity this situation requires. The Commission has general anti-manipulation authority under the CEA, but applying it to a candidate who trades on knowledge of his own candidacy requires a threshold finding that the contract is within CFTC jurisdiction in the first place. The Moran incident does not resolve that question. It demonstrates why the question costs something to leave unresolved.

Warren and Curtis did not call for a ban. They called for information. That is a more durable move than legislation, because the response — whatever it contains — becomes part of the record that regulators and courts will read. If Mansour and Coplan confirm that referrals to the CFTC have been rare or absent, that answer will follow every future preemption argument Kalshi makes about the adequacy of federal oversight.