If you have ever looked at a sportsbook app, you know the visual language: a minus sign, a plus sign, a payout number. The U.S. agency that oversees derivatives just told regulated prediction markets to drop that look.
Bloomberg reviewed the letter, which went to every exchange running event contracts, a person familiar with the matter said. Event contracts are agreements that pay out based on the outcome of something in the real world, like a sports result or an election.
In the letter, the Commodity Futures Trading Commission, also known as the CFTC, reminds the firms it regulates to follow U.S. derivatives law and avoid misleading conduct when they list, pitch, or advertise products. The instruction is concrete: show prices as direct dollar amounts or percentages tied to market pricing, not as bookmaker-style lines with a plus or minus sign and a payout number.
The agency says the bookmaker look may mislead traders about what they are buying and could push them toward betting products that are more profitable for the platform. A footnote in the letter cites a study that found this style of odds increases risk-taking by sports bettors.
CFTC Chairman Michael Selig had already raised concerns about this kind of marketing, so the worry is not just whether a price is easy to read. It is whether the format nudges people to bet bigger.
The difference is more than looks. Bookmaker-style odds are a familiar cue from gambling apps, while dollar and percentage prices are the language of financial markets.
Get the free Always Be Buying eBook and learn the simple system for building wealth on any income
The letter is not a ban on event contracts. It is a warning about how they are presented, and it sets a hard date for regulated firms to get on board.
The warning lands in the middle of a legal fight over what prediction markets actually are. States are suing the industry, arguing that regulated prediction markets allow illegal gambling even where betting is banned.
The CFTC and the platforms say these products are derivatives. States say they are unlicensed gambling operations.
Kalshi and Polymarket, two of the biggest names in the space, let users place bets on sports, reality TV, and geopolitics. Sports betting is the largest slice of prediction-market trading, and it is the main issue in the fight over this multibillion-dollar industry.
The industry has expanded quickly since President Donald Trump took office again. Donald Trump Jr. holds advisory roles with both Kalshi and Polymarket, and in May Trump backed exclusive CFTC authority over prediction markets, calling it "critically important."
The federal agency is trying to set the rules, while state lawsuits ask courts to treat the products as illegal gambling. The letter is one more move in that tug-of-war.
Kalshi said it will meet the deadline.
Jacki McGavick, a Kalshi spokesperson, said: "As a federally regulated exchange, Kalshi follows CFTC guidance and will comply with the letter by its deadline." Polymarket did not immediately comment.
For investors who use these platforms, the visible change is that flashy betting lines may disappear from regulated sites, replaced by plain pricing that looks more like a financial market. That design shift is part of a bigger question: whether prediction markets will be treated as legal derivatives or as illegal gambling.
The answer will shape where this fast-growing industry is allowed to operate and how it looks when you open an app. For anyone with money on one of these platforms, the next few months will decide whether these markets can keep selling these bets at all.
Download the free Always Be Buying eBook and start putting your money to work today