Google bans prediction market extensions from Chrome Web Store

Google has updated its Chrome Web Store Developer Program Policies to bar extensions that enable or facilitate real-money trading on prediction markets, including tools used with platforms such as Polymarket and Kalshi. The changes were announced July 1 and take effect August 1, 2026, placing such extensions under Google's prohibited regulated goods and services while leaving the underlying websites and mobile apps accessible. The update arrives as prediction market activity scales rapidly, with combined monthly notional volume reaching $291.38 billion as of June 22, according to Dune data. The policy overhaul also tightens rules on extension data collection, limiting developers to data strictly necessary for a single disclosed purpose and requiring prominent disclosure of data practices and later changes. Google also added a separate ban on tools designed to circumvent safety guardrails in AI-powered services, saying the changes are aimed at trust and user visibility. The move creates a new distribution chokepoint for the sector and sits awkwardly alongside Google's own integration of Kalshi and Polymarket data into Google Finance in November 2025. The ban lands as legal and geographic restrictions continue to build around prediction markets. Argentina ordered a nationwide block of Polymarket in March and required Google and Apple to remove its apps for Argentine users, adding to a list of more than 30 countries with restrictions. In the United States, the Commodity Futures Trading Commission is defending the sector in litigation tied to a Kentucky crackdown and related state cases including New York and Wisconsin. Capital has continued to flow into the industry, with Kalshi reportedly seeking a $40 billion valuation months after a $1 billion Series F, even as a Wall Street Journal analysis found that more than 70% of Polymarket accounts lost money and 0.1% of accounts captured 67% of profits.