Prediction markets and sports betting are not forms of investing, despite how some fans portray them.

Prediction markets—the platforms where users can trade bets that pay out depending on certain event outcomes—have faced questions about insider trading.

Prediction market Kalshi's CEO Tarek Mansour ​​has said that prediction markets are similar to the stock market—except instead of buying and selling shares of companies, users buy and sell "yes" or "no" on whether an event is going to happen or not.

How prediction markets differ from sportsbooks matters for regulation

There are a number of differences and similarities between sportsbooks and prediction markets, despite both allowing people to bet on outcomes for sports-related events. For instance, prediction markets typically earn revenue through transaction fees rather than taking directional exposure to outcomes.

Prediction markets help people bet on almost anything—which can be controversial

Critics point to incidents such as traders placing bets on the Venezuelan President Nicolás Maduro's capture and the two people in Israel who were charged on suspicion of using classified information to place bets about military actions.

The 2024 US presidential election was a breakthrough moment for prediction markets

Founded in 2018 by MIT graduates, Kalshi won a federal appeals court ruling in October 2024 that allowed it to offer election contracts in the US. When prediction markets predicted President Donald Trump's win (more accurately than most polls), prediction markets were thrust into the public eye.

Kalshi is the first regulated prediction market in the US

Two migrant MIT students, Luana Lara Lopes and Tarek Mansour, shared an interest in hedging against uncertainty—from election outcomes to the Oscar awards. They fought hard for regulatory approval and their company now has a valuation in the billions. The platform has brought prediction markets into the mainstream.

Some experts equate prediction markets to the new crack cocaine of gambling addiction

An addiction psychiatrist at UCLA says betting apps are far more potent than traditional gambling, citing a 19-year-old patient who lost $180,000 and hadn't left campus in a year, cycling through sports bets, crypto, meme stocks, and prediction markets on his phone. This interview explores the extreme edge of the nascent industry.

Modern prediction markets—the platforms where people can trade bets that pay out depending on certain event outcomes—started in Iowa in 1988.

The prices on prediction markets reflect how the collective forecasts future outcomes

On prediction markets, bettors bid up or down the price of contracts based on what they expect an event's outcome to be. Bettors bid up prices when they think an event is more likely to occur than the current contract price shows, so they buy the contracts, pushing the price higher. They bid down prices by selling these contracts when they believe an event is less likely to occur, driving the price down due to supply and demand.

Contract prices on prediction markets are generally interpreted as implied probabilities

For example, if a contract trading is at $0.65, that could be read as the market assigning a 65% probability to that event occurring. The most common format for prediction markets is winner-take-all: The contract settles at $1 if the event occurs, or $0 if it doesn't.

Commodity trading is regulated by the CFTC to mitigate fraud and risk

Established in 1974, the CFTC regulates these markets (including swaps, futures, and certain types of options) to protect market participants from fraud, ensure fair trading conditions, and generally reduce financial risk.

Sports betting, explained

Since a 2018 Supreme Court decision overturned the Bradley Act, which spurred a state-by-state legalization of online gambling, sports betting has become a rapidly growing multibillion-dollar industry.

The CEOs of the two top prediction markets have a fierce rivalry

Kalshi CEO Tarek Mansour and Polymarket CEO Shayne Coplan are both billionaire CEOs of the top two prediction markets—but they don't exactly get along. For instance, Mansour reportedly does not say the word "Polymarket" out loud, referring to it as the "non-American, unregulated platform."

Use a prediction market profit or loss calculator

In order to calculate how much someone would make from a specific trade on a prediction market, this calculator asks for the purchase price of a given "yes" or "no" prediction, the number of contracts the trader plans to purchase, and more.

Prediction markets have their own lingo that's an amalgamation of Gen Z and Gen Alpha slang

For instance, if you've been out-maneuvered by another trader, you've been "mogged." A "rulescuck" is someone who is a stickler for betting market rules and may try to win on a technicality.

Kalshi announced a partnership with CNN in 2025

The partnership included an integration of Kalshi's prediction markets data across CNN's network programming. For instance, certain TV segments on CNN could show a scrolling banner detailing the odds of event contracts on the exchange.

Futures contracts—which are agreements to buy or sell a standardized asset at a specific future time—are the primary way commodities are bought and sold.

Experts suggest the industry could be a $45B business

Sports betting used to primarily consist of who would win and the points spread, but the rise of online betting apps has fueled a substantial increase in parlay bets. "Existing markets are still growing at a rapid clip," said Noah Naparst, who evaluates sports-betting companies for Goldman Sachs. "So we’re not mature yet, but we’re not in the early wildcat days of the market anymore, either.”

Sports leagues have attempted to prevent athletes from betting

As pro and collegiate sports embrace betting (and the revenue that comes with it), each league works diligently to ensure the integrity of the games by hiring private firms to analyze irregular bets. These companies have flagged bets that led to the firing of Alabama’s baseball coach, the suspension of multiple athletes at Iowa and Iowa State, and, most recently, a lifetime ban on former Toronto Raptors forward Jontay Porter by the NBA in April 2024.

Futures contracts are agreements to buy or sell a standardized asset at a specific future time

When it comes to commodity trading, these legally binding agreements tend to operate on a monthly basis. Futures contracts are typically traded on futures exchanges, like those operated by CME Group and the Intercontinental Exchange.

Commodity traders are most commonly 'hedgers' or 'speculators'

While hedgers often produce and consume physical commodities (like corn, copper, or natural gas) and use the markets to manage the price risk for those commodities, speculators provide liquidity by betting on commodity price changes.

How exchanges like the Chicago Mercantile act as trading referees

Chicago's Mercantile Exchange emphasizes futures contracts on commodities. This podcast episode breaks down how exchanges actually work, make money, and streamline the market.

Donald Trump's Truth Social social media platform is launching a prediction market

Named "Truth Predict," the cryptocurrency-based prediction market will allow users of the Truth Social social media platform to place crypto bets on the outcome of certain events (think: sports games, the economy, and political races). Truth Social is primarily owned by President Donald Trump and his family.

Some experts and investors think short selling—a strategy in which investors bet that a stock will drop in value—helps keep the market healthy.

Frictionless online gambling platforms accelerate compulsive behavior

As of late 2025, as much as 95% of bets are placed online, where "always on" betting and a variety of formats, such as prop bets and parlays, encourage users to keep participating. Experts warn that the normalization of gambling through advertisements also reduces the perceived danger of addictive gambling.

A prediction market was more accurate than most polls about the 2024 US presidential election

The idea that the median estimate of a group can be more accurate than individual expert estimates is called the "wisdom of the crowd," and dates back to the early 1900s. This theory can help explain the perceived value of prediction markets when it comes to polling and more.

Decoding sports-betting language

The world of sports gambling is filled with insider lingo: What's a "spread"? How about a "moneyline" or a "parlay"? This resource breaks down the jargon, helping you navigate the industry or, at least, giving you the keys to talk about it.

Read about why bans on short selling are a controversial policy

Generally, short selling is legal, but regulations often restrict short positions when a stock has experienced a sharp price decline (more than 10% in one day). However, negative feedback loops in times of financial crisis have given short selling a bad reputation. The government has temporarily banned short selling during previous market downturns—like The Great Recession of 2008 and the early months of the COVID-19 pandemic—but experts argue whether those bans actually improved market stability or just distorted prices.

A timeline of sports-betting scandals

This timeline examines memorable moments from three decades of sports-betting history. It breaks down key political moments, as well as some historical moments such as when the internet pushed underground bookmaking online. There are also multiple descriptions of betting scandals from 1989 on.

Sports media have also embraced sports betting

For decades, ESPN kept its distance between reporting on games and talking about gambling lines. Sports teams refused to have franchises in Las Vegas, fearing it would harm the sport. But since 2018, that has changed. ESPN’s personalities regularly pick games, and the company has also launched its own betting app.

A 2024 cheating scandal cast doubt on the industry

In 2024, National Fantasy Football Championship, a fantasy league with big payouts, fired one of its employees for manipulating data. The episode cast doubt on the relatively unregulated industry, despite the league coming down hard on the nefarious worker.

Even athletes aren't immune to the sports-betting craze

While gambling scandals occasionally blew up before 2018, the widespread legalization of sports betting provided athletes with more opportunities to bet on the games they were playing.

A 1954 Supreme Court ruling helped quiz shows avoid regulation

When the Federal Communications Committee attempted to rein in giveaway shows, the Supreme Court ruled that quiz shows were not a form of gambling because contestants did not have to risk anything to participate. Some believe that the ruling prevented proper oversight of the industry as it became more popular.

How math whizzes exploit sportsbooks

Chris Dirkus is a professional sports bettor who approaches the hobby as a math problem, not from a fan's perspective. He focuses on mispriced odds in popular games where many fans are betting for high liquidity. He's one of a rare segment of sports bettors exploiting slow models and human mistakes.

Insider trading is the practice of trading a company's securities based on material, nonpublic information.

A landmark hedge fund court case once reshaped high finance

Hedge fund traders tied to insider trading by probing prosecutors are relatively rare. When billionaire hedge fund legend Steve Cohen, founder of SAC Capital, pleaded guilty to trading on inside information, Wall Street trembled. The outcome of the case remains a cautionary tale for traders today.

Play a game that reveals if investors with a crystal ball make better trades

The "crystal ball" game reveals how well you would do trading stocks and bonds if you could see the front page of the Wall Street Journal one day in advance.