I've long been skeptical of the potential of prediction markets. A huge source of their recent growth, sports-related contracts, seems to rest on precarious legal grounds since none of the major players are registered sports betting outfits. There's a lot of activity around political betting, but these are concentrated around presidential and midterm election seasons. Is there really enough betting volume to justify an $8B valuation? What % of that volume will they be able to capture as fees? Over the past few years, the retail brokerage market has trended towards eliminating trading fees in favor of payment for order flow. Could the same happen to prediction markets?