If one trader can force the outcome of a prediction market, it shouldn’t be tradable

Prediction markets, like Polymarket, risk collapsing their promise of aggregating truth if their contracts create a financial incentive for a single actor to manipulate the outcome they measure. This vulnerability is highest in thinly traded, event-based contracts, such as political or cultural markets, where a discrete milestone can be nudged or staged at low cost—turning the contract into a script rather than a prediction. The standard defense that manipulation exists everywhere misses the point; the critical issue is whether manipulation is feasible for a single participant. Sports markets serve as a structural template because their high visibility and multi-actor outcomes make individual corruption costly. Platforms must adopt a bright-line rule: do not list contracts whose outcomes can be cheaply forced or that function as bounties on harm. Failure to impose these listing standards internally will lead to external regulation, as the first major scandal will frame the entire category as monetizing interference with real-world events.

(Source：CoinDesk)