A man at Paris Charles de Gaulle Airport used a portable heat source to manipulate a weather sensor, resulting in a $34,000 profit on the Polymarket weather market. By understanding the source of market settlement data, he influenced the recorded temperature to settle at 22°C, highlighting vulnerabilities in prediction markets where participants can affect outcomes. This incident underscores broader concerns about prediction markets, where the incentive to influence reality can lead to manipulation. Markets dependent on single-point data sources, insider knowledge, or where participants can directly alter outcomes are particularly susceptible. Platforms like Kalshi and Polymarket have differing approaches to handling such vulnerabilities, with Kalshi enforcing strict penalties and Polymarket focusing on market accuracy through insider information.