Comer Asks Prediction Markets About Insider Trading
On 29 September 2026 James Comer sent letters asking three prediction-market firms how they verify identity and detect insider trading. A May inquiry into Kalshi and Polymarket remains open.
On 29 September 2026, House Oversight Chair James Comer sent letters to the chief executives of Hyperliquid Labs, Crypto.com, and Aristotle Exchange. The House Oversight prediction market insider trading letters ask how those firms verify identity and how they detect insider trading. The committee's May inquiry into Kalshi and Polymarket is still open. Both accounts say the committee has received nearly 1,000 documents and five briefings from those two firms.
What happened
The date on the letters, in both accounts, is 29 September 2026. The sender is James Comer, chair of the House Oversight Committee. The recipients are the chief executives of three firms: Hyperliquid Labs, Crypto.com, and Aristotle Exchange. The letters ask two operational questions. How does the firm verify identity? How does the firm detect insider trading? Those questions are the content this article will treat as established. A longer paraphrase of the letters would start to invent wording the shared record does not quote.
The May inquiry is a separate track, and it is not closed. It concerns Kalshi and Polymarket. Both pages say the committee has received nearly 1,000 documents and five briefings from those two firms. "Nearly 1,000" is the document figure. Five is the briefing figure. The firms attached to those figures are Kalshi and Polymarket, not the three companies that received the new letters. Mixing the piles would overstate what Hyperliquid Labs, Crypto.com, or Aristotle Exchange have already turned over. The accounts used here do not assign the document count or the briefing count to them.
Insider trading, in the ordinary sense of the question Comer is asking, is trading on material information that the rest of the market does not have, by someone who was not supposed to use it. Identity verification is the separate question of whether a platform knows who is trading. The letters put those two questions to three prediction-market businesses. This article does not supply an example trade, a market title, or a profit figure. None of that is in the shared account of the 29 September letters.
The inquiry's age is stated only as May. The year of that May is not part of the facts used here, and this article will not fill it in. What both pages support is that the Kalshi and Polymarket inquiry remains open while the chair sends a new set of letters to three other firms.
Why it matters
Prediction markets pay people for being right about a future event. That structure is why an oversight chair would ask about insider trading at all. If a person who already knows the outcome, or who knows it before the public does, can still trade, the price is not a public forecast. It is a transfer from everyone else to the person with the early fact. Asking how a platform detects that pattern is an oversight question about fairness and about whether the market is doing the informational job it advertises. It is not, in these pages, a finding that any named firm failed.
Identity verification sits beside that question because a detection program that cannot tell users apart cannot say who traded on the early fact. The letters ask how identity is verified and how insider trading is detected. They are related questions. They are not the same question. A firm could have a strong identity check and a weak detection program, or the reverse. Comer's letters, as described, request an account of both. They do not, in the shared record, grade the answers. No answer is described here.
The open May inquiry is the context that keeps the new letters from looking like a first contact with the industry. Kalshi and Polymarket have already been asked, on this record, and the committee has nearly 1,000 documents and five briefings from them. The investigation those materials belong to is still open. The 29 September letters widen the set of firms being questioned. They do not, by themselves, close the earlier file or announce a result.
Scope is the constraint a careful reader should keep. Three new addressees. Two questions, identity and insider-trading detection. An older inquiry, still open, covering two other firms, with a stated volume of documents and briefings. That is a congressional information demand. It is not a charge, not a sanction, and not a market move. Nothing in the accounts used here alleges a specific insider trade at Hyperliquid Labs, Crypto.com, or Aristotle Exchange.
What's next
The May inquiry into Kalshi and Polymarket remains open, with nearly 1,000 documents and five briefings already received from those two firms. The new letters ask Hyperliquid Labs, Crypto.com, and Aristotle Exchange to explain identity verification and insider-trading detection. What those three firms say in reply is not in the accounts used here.
This article does not predict what the committee will conclude. The news is the letters, the two questions, and the still-open inquiry with the document and briefing counts both pages report. For related prediction-market context, see Kalshi volume incentives and Polymarket deposit limits.
This article is for information only and is not investment advice.