Kalshi’s $22 billion problem

Grant Mainland had a tough day at the office earlier this week. A lawyer representing the prediction markets platform Kalshi, Mainland appeared before the Massachusetts Supreme Judicial Court on May 4 with an unenviable task: persuading the justices that a company that has literally advertised itself as the “first app for legal sports betting in all 50 states” is not, technically speaking, offering people the opportunity to bet on sports. Mainland was hoping to get the court to overturn a lower state court injunction that blocked Kalshi from offering its “markets” related to sports within the commonwealth’s borders. Thanks primarily to these sports markets, which accounted for nearly 90% of its revenue in 2025, Kalshi has hit $1.5 billion in annualized revenue. It’s a growth story that investors are clearly buying: Kalshi recently announced it raised a $1 billion Series F, catapulting the company to a $22 billion valuation—double what it was worth just six months ago. For the uninitiated, Kalshi allows users to make money by correctly predicting the yes-or-no outcomes of real-world events. Users are able to buy and sell contracts at prices that range from 1 cent to 99 cents, which roughly approximate the market’s sense of the percentage chance that an outcome will occur. When that market “resolves” (i.e., the event either happens or doesn’t), those who hold shares in the winning position are paid out at $1 per share. If, for example, my beloved Seattle Seahawks return to the Super Bowl next year, anyone who bought in at 14 cents per share—the price as of this writing—will enjoy a nice payday. If this sounds to you like futures betting by another name, you’re not alone. In January, a lower court judge found that Kalshi, by allowing users to buy and sell “event contracts” on everything from final scores to player props, was functionally operating in Massachusetts as an unlicensed sportsbook. There is “no question,” Judge Christopher Barry-Smith wrote, that requiring K