What Polymarket knows: The rise of a new insider trading

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An account called "Magamyman" placed an $87,000 bet on U.S. strikes against Iran roughly 71 minutes before news of the attacks broke publicly. The odds at the time sat at 17%. By the time the smoke cleared over Tehran, the position had turned into more than $553,000.

That trade — and at least five others like it, flagged by blockchain analytics firm Bubblemaps as netting a collective $1.2 million — is the clearest illustration yet of what prediction markets have quietly become. Not just a novel forecasting tool or a quirky corner of the internet where people bet on Oscar winners and Federal Reserve decisions, but a live, liquid market where anyone with advance knowledge of world events can monetize it, including, apparently, a military campaign.

Over $529 million was traded on Polymarket contracts tied to the timing of U.S. strikes on Iran and the fate of Supreme Leader Ali Khamenei. For context, the platform's entire weekly trading volume hit a record $3.7 billion earlier this year. War, as we know, can be good for business, including prediction markets apparently.

These markets earned their reputation the hard way

To understand why the Iran trades matter, it helps to understand why anyone takes prediction markets seriously in the first place.

Polymarket's big moment came during the 2024 presidential election, when it consistently gave Donald Trump better odds than traditional polls while the platform's contracts moved toward 60 cents on the dollar for a Trump win as Election Day approached. 

When Trump won, Polymarket's total presidential contract hit $3.6 billion. CEO Shayne Coplan claimed the Trump campaign "literally found out they were winning from Polymarket" before the networks called it. Media coverage exploded. The platform became, almost overnight, a legitimate forecasting tool that journalists, traders, and political operatives began treating as a real-time signal.

The theoretical justification is straightforward. Aggregate enough independent traders putting real money on outcomes, and prices reflect genuine collective belief and not the hedged opinions of pundits or the self-interest of pollsters. 

The flip side of that logic is now apparent in the Iran data. If money focuses the mind, it also rewards whoever has the best information. And the best information about a military strike is, by definition, highly classified.

Inside information is the feature — until it isn't

Polymarket runs offshore, largely outside U.S. jurisdiction, and publishes every transaction to the blockchain where anyone can see them. Coplan has described insider-informed trades as "sort of an inevitability" with "a lot of benefits." When a blockchain record shows six freshly funded accounts placing winning bets in the hours before a strike, the wisdom-of-crowds framing starts to strain.

This isn't the first time suspicious timing has raised questions. In January, a mystery trader made roughly $410,000 betting on the capture of Venezuelan President Nicolás Maduro hours before U.S. forces seized him. 

Before that, a trader known as the "Google $GOOGL whale" made over $1 million on Google-related markets, including one on the most-searched person of the year. 

An analysis of Polymarket's blockchain found clusters of suspicious trades around OpenAI product launches going back to 2023. The accounts were all created recently, funded quickly, and gone after the payout. OpenAI has since confirmed firing at least one employee over prediction market trades made with confidential company information.

Kalshi, the U.S.-regulated rival, has tried to draw a clean line. It bans war markets outright, has run over 200 insider trading investigations, and suspended a MrBeast editor and a California gubernatorial candidate for trading on privileged information.

Prediction markets are now a fixture of how the media, campaigns, and financial traders understand the world in real time. The Iran trades are what the system looks like when the information asymmetry is as stark as it gets. Some Democratic lawmakers have started calling for legislation, and it is probably not the last time someone in Congress will say the words "Polymarket" and "national security" in the same sentence. 

But the harder question isn't whether this should be regulated. It's whether the same quality of information that makes these markets useful is separable from the quality of information that makes them dangerous.