Opinion: If a single trader can manipulate the outcome of a prediction market, that market should not be listed for trading.

Odaily reported that as prediction market platforms such as Polymarket gain mainstream attention during the US election cycle and geopolitical events, their prices are increasingly cited as real-time signals. However, this premise fails when contracts create economic incentives for participants to alter the outcomes they are measuring.

The core issue lies in product design rather than volatility. When a result can be achieved by a single actor through a single action, the contract shifts from a prediction tool to an execution script. The article uses the example of betting on someone storming the Super Bowl field, noting that traders who bet "yes" may personally carry out the act—such incidents have actually occurred.

Political and event-based markets are particularly vulnerable, as they often rely on discrete nodes that can be influenced at low cost and have thin liquidity. If participants begin to suspect that outcomes are being artificially manufactured, the platform will lose credibility. The article argues that sports markets, due to their high visibility, multi-layered governance, and multi-party participation structure, are much harder to manipulate at the individual level and should serve as a structural reference.

Prediction market platforms should establish clear listing standards, excluding contracts that can be manipulated at low cost by a single participant or constitute harm bounties; otherwise, external regulation will intervene.