A new academic paper suggests there\u2019s been a steady stream of \u201cfree money\u201d lying around on Polymarket\u2014and smart traders have been scooping it up.<\/p>\n
The paper, Unravelling the Probabilistic Forest: Arbitrage in Prediction Markets, is the most detailed look yet at how mispricing creeps into crypto\u2019s most popular prediction platform. The researchers combed through a year of data, from April 2024 to April 2025, and found thousands of instances where market prices simply didn\u2019t add up.<\/p>\n
In some cases, the prices of \u201cYes\u201d and \u201cNo\u201d shares in a single market didn\u2019t sum to one dollar as they theoretically should, creating a risk-free profit for anyone quick enough to pounce.<\/p>\n
In other cases, the mispricing was more subtle, involving logically related markets. For example, a market on \u201cTrump wins the presidency\u201d might trade at very different odds than \u201cRepublican wins the presidency,\u201d even though those outcomes are tightly linked. By buying and selling combinations of these contracts, a savvy trader could lock in a profit no matter what happens.<\/p>\n
The researchers estimate more than $40 million in profits have already been pulled from the system by arbitrageurs, traders who specialize in sniffing out and exploiting these kinds of inconsistencies. Far from being a theoretical curiosity, this is a live and lucrative business model.<\/p>\n
What\u2019s striking is how common these opportunities are. The study found more than 7,000 markets with measurable mispricing, many in highly liquid, closely watched contracts.<\/p>\n
\u201cPrediction markets are often treated as if they represent the collective intelligence of the crowd,\u201d the authors write. \u201cBut our results show they can deviate significantly from probabilistic consistency, even in markets with substantial trading activity.\u201d<\/p>\n
It raises a broader question: Is this just Polymarket, or is it prediction markets in general? The answer is probably both.<\/p>\n
Why Are Myriad Users Betting on the Color of Fed Chair Powell’s Tie Today?<\/a><\/p>\n Any exchange that allows continuous, peer-to-peer trading of outcome tokens\u2014whether on crypto rails like Polymarket and Decrypt’s sister site, Myriad<\/a>, or in regulated venues like Kalshi\u2014is subject to the same structural forces. Liquidity can be fragmented across multiple related markets, traders can miss obvious relationships, and prices can temporarily drift apart.<\/p>\n In traditional finance, such inefficiencies tend to get arbitraged away quickly by algorithmic market-makers. The same is now happening in prediction markets. Sophisticated players, often running bots, monitor dozens of markets simultaneously, ready to deploy capital when they spot an inconsistency. Their activity helps bring prices back in line\u2014but not before they\u2019ve taken their cut.<\/p>\n Story Continues <\/p>\n