When Iranian Supreme Leader Ayatollah Ali Khamenei was killed in US-Israeli airstrikes on 28 February 2026, thousands of traders on the Kalshi prediction market platform believed they had won. They had correctly wagered that he would leave office before March 1. Kalshi offered contracts asking whether Khamenei would leave office before March 1, 2026. The market was worth $54 million.
Then Kalshi invoked what it calls a "death carveout." According to the lawsuit, Kalshi did not invoke a "death carveout" provision until after the Iranian leader was killed to avoid paying customers what they were owed. Instead of paying $1 per winning share, the platform resolved the market at the last traded price before Khamenei's death. Winners received far less than expected.
The result: A class-action lawsuit was filed on Thursday alleging Kalshi failed to pay $54 million to people who bet that Khamenei would leave office before March 1.
The case for the traders
The plaintiffs argue the market terms were crystal clear. The lawsuit states that with an American naval armada on Iran's doorstep and military conflict widely anticipated, consumers understood that the most likely mechanism for an 85-year-old autocratic leader to leave office was through his death. The contract language asked simply whether he would "leave office"—it did not exclude death as a mechanism.
The complaint argues the contract language was "clear, unambiguous and binary" and accuses Kalshi of "deceptive" and "predatory" conduct.
The traders also point to disclosure. Plaintiffs allege the death carveout rule upon which defendants relied was not adequately disclosed at the time they entered into their trades. Kalshi allowed continuous trading even as news of Khamenei's death began circulating, compounding the alleged unfairness.
Kalshi's defence
The platform contests the characterisation entirely. CEO Tarek Mansour defended the "death carveout," saying it "keeps the rules simple." More substantively, Kalshi argues the rule was not newly invented; it has long been part of platform policy.
A Kalshi spokesperson said the company's rules were clear from the start as they "included every precaution to make sure people could not trade on the outcome of death." The company reimbursed all fees and net losses out of pocket to the tune of millions of dollars to make sure not a single person lost money on this market. Kalshi lost $2.2 million refunding all fees and net losses from this market, making everyone whole.
The company argues that preventing traders from profiting directly from death is ethically sound and legally defensible. Kalshi's CEO said the company does not list markets directly tied to death, and when markets involve potential death outcomes, the company designs rules to prevent people from profiting from death.
The regulatory elephant in the room
What neither side disputes is that prediction markets operate in a patchwork regulatory environment. Prediction markets have exploded in popularity since the 2024 US election, when their real-time probabilities proved more accurate than polling in forecasting Donald Trump's victory.
Yet the industry remains fragmented. Total trading exceeded $60 billion in 2025, a 400 per cent increase from 2024. Federal regulators are playing catch-up. Michael Selig, the Trump-appointed head of the Commodity Futures Trading Commission, which regulates prediction markets, has been supportive of companies in this space. He said the Trump administration will soon issue new rules and guidance.
The Khamenei market also raised deeper concerns. Other sizable and well-timed bets, placed mere hours before airstrikes began, correctly predicted that strikes would soon occur, raising questions about whether there was insider trading by government officials or others who knew the war plans ahead of time.
A genuine tension
The dispute captures a real policy dilemma without easy resolution. Allowing traders to profit from death creates perverse incentives; there is a reason fire insurance policies cannot be taken out on other people's homes because it would incent arson. Yet if markets exist that rationally depend on death as an outcome, refusing to acknowledge that outcome after the fact looks like rule-shifting.
Kalshi could have added "by way other than death" to the trade terms, but it did not, presumably because that language would have deterred users from betting. This raises the uncomfortable question of whether Kalshi wrote ambiguous terms by design, betting most traders would not read the fine print.
The broader issue is disclosure and institutional accountability. Prediction markets are regulated by the federal government, which requires platforms to follow clear rules and protect customers. When platforms invoke rules users claim they did not adequately understand, trust erodes.
If 2025 marked the breakout year for prediction markets, 2026 is shaping up to be the year of regulatory reckoning. What began as a niche financial innovation has rapidly evolved into a flashpoint across the US gaming, regulatory and political landscape.
Whether Kalshi's legal position ultimately prevails, the Khamenei market has exposed genuine deficiencies in how prediction markets disclose their rules and manage edge cases. As the sector expands globally, clearer disclosure requirements and independent dispute resolution mechanisms will be essential if these platforms are to maintain legitimacy beyond their enthusiast user base.