Polymarket, Kalshi Take Steps to Block Fraud Rings

Polymarket and Kalshi are racing to turn more major events into opportunities to place bets, including everything from daily temperature highs during a New York City heat wave to the latest contestant to be eliminated from “Love Island,” the reality TV hit. That’s helped the young markets become high-profile sentiment gauges and generate meaningful revenue, with Kalshi’s annualized revenue hitting around $1.5 billion in May and Polymarket pacing at roughly a quarter of that based on trading...