As the World Cup heats up, the weekly nominal trading volume in prediction markets has surpassed $15 billion, with open interest exceeding $2 billion. - Kalshi's weekly nominal trading volume broke $10 billion, with open interest reaching $1.3 billion. - Polymarket's weekly nominal trading volume hit $3.6 billion, making it one of only two prediction markets to surpass the billion-dollar level, with open interest at $560 million. - Robinhood's in-house compliant prediction market, Rothera, was the biggest surprise this round, with weekly nominal trading volume exceeding $900 million, ranking third, and open interest surpassing $110 million. - For other smaller prediction markets, the spillover in trading volume from the World Cup hype hasn’t been very noticeable, maintaining a 'strong get stronger' dynamic.