Google’s Chrome Ban on Prediction Market Extensions Adds to Sector’s Legal Woes

Google has moved to bar Chrome browser extensions that facilitate prediction market trading, a policy shift that adds a new layer of distribution risk for platforms such as Polymarket and Kalshi at a moment when the sector is recording record trading volumes and remains entangled in litigation across several US states.

The change was announced on 1 July via the Chrome for Developers blog, according to TokenPost, and expands Google’s existing Regulated Goods and Services policy to explicitly prohibit extensions that enable participation in predictive markets. Developers who fail to bring their extensions into compliance risk having them removed from the Chrome Web Store once the policy takes effect.

A gatekeeper role for Google

The restriction is notable given Google’s own commercial ties to the sector. Google Finance has displayed Polymarket and Kalshi market odds since November 2025, and the company appears set to continue featuring that pricing data even as it restricts browser tools that allow users to trade directly through extensions. The distinction — permitting data display while blocking transactional access at the browser level — illustrates how large technology platforms are increasingly acting as informal gatekeepers for markets that regulators have yet to fully settle on classifying.

Alongside the prediction market clause, Google introduced broader privacy requirements for all Chrome extensions, limiting data collection to what is necessary for a clearly disclosed function and mandating transparency over any future changes. The company also said it would ban extensions built to circumvent safety guardrails in AI-powered services, framing the overhaul as an effort to reinforce trust in the extension ecosystem.

Growth collides with legal pressure

The policy lands as prediction markets expand at pace. Combined monthly notional trading volume across the sector reached approximately $291.38 billion as of 22 June, according to Dune Analytics data cited by TokenPost. That growth has not shielded the industry from regulatory friction. Argentina ordered a nationwide block of Polymarket in March, joining more than 30 countries that have restricted access to the platform, a ruling that also prompted Google and Apple to remove Polymarket’s mobile applications for Argentine users.

In the United States, the Commodity Futures Trading Commission continues to defend the legality of prediction markets in court against challenges brought by several states, including Kentucky, New York and Wisconsin. The CFTC’s position has become a central battleground for determining whether such platforms fall under federal commodities oversight or are subject to state-level gambling restrictions.

Investor appetite persists despite the risks

Institutional interest in the sector has not slowed. Kalshi is reportedly pursuing a $40 billion valuation following a $1 billion Series F funding round, underscoring investor confidence in the category’s long-term commercial prospects even as regulatory and platform-level obstacles accumulate.

That confidence sits uneasily alongside user-level outcomes. A Wall Street Journal analysis found that more than 70 per cent of Polymarket accounts lost money, while just 0.1 per cent of users captured roughly 67 per cent of total profits — a concentration pattern that regulators weighing consumer-protection frameworks are likely to scrutinise closely.

Chrome extensions represent only one distribution channel among several; prediction markets remain accessible via dedicated websites and mobile applications. But the removal of browser-based access tools, layered atop existing court battles and country-level bans, adds to a pattern in which prediction markets face mounting friction from regulators, platform operators and app store gatekeepers simultaneously.

Read more: Kalshi Escalates Prediction Markets Fight to Second Circuit After New York Setback