Polymarket and Kalshi are closely tied for market share. Credit: Absolute Charm via Pexels. Key Takeaways Intercontinental Exchange (ICE) will invest up to $2 billion in Polymarket. The deal sees Polymarket’s valuation overtake rival Kalshi’s. However, trading volume on two prediction markets remains close. Intercontinental Exchange (ICE) is investing up to $2 billion in Polymarket, the New York Stock Exchange-owner announced on Tuesday, Oct. 7. The deal values Polymarket at $8 billion—four times ...