On the latest episode of HBO’s Last Week Tonight, host John Oliver took aim at prediction-market platforms such as Kalshi and Polymarket, arguing they offer trivial, easily manipulated event contracts and raise thorny legal and ethical questions. Oliver highlighted contracts that let users bet on whether specific public figures would use certain words or whether companies would partner with particular news outlets. He also flagged advisory ties between Donald Trump Jr. and the platforms, and criticized the Commodity Futures Trading Commission, led by Chair Michael Selig, for apparently not blocking event contracts tied to terrorism, assassination and war.
Oliver warned that it is “incredibly easy for individuals to manipulate the outcomes,” pointing to a notable episode when Coinbase CEO Brian Armstrong rattled off crypto-related terms during a third-quarter 2025 earnings call — an action that allowed many Kalshi and Polymarket bettors to collect on related contracts. He mocked the notion that public figures would change behavior to move these markets, quipping that he wouldn’t placate bettors.
User activity and trading volume on prediction markets have surged recently, and some projections estimate the market could reach $1 trillion by 2030. That growth has attracted partnerships with media outlets such as CNN, CNBC, Fox News and Dow Jones, and caught the attention of traditional financial firms. Charles Schwab CEO Rick Wurster said the firm would “take a hard look” at the space, while Citadel Securities president Jim Esposito said the company is watching developments closely.
At the same time, the industry faces legal scrutiny. Gaming regulators in several U.S. states have sued Kalshi and other companies, alleging illegal sports betting, and legal leaders including Coinbase chief legal officer Paul Grewal have suggested the disputes could ultimately land before the U.S. Supreme Court.
Oliver’s segment raises broader questions about where prediction markets fit in the regulatory landscape, how easily outcomes can be influenced by public remarks or coordinated behavior, and how to balance innovation with consumer protection. Cointelegraph states it is committed to independent, transparent journalism and encourages readers to verify details independently.