A coalition of 30 federally recognized American Indian tribes and 11 Indian regulatory agencies filed amicus briefs this month challenging Kalshi and the CFTC over prediction market access on Indian land. The coalition said the actions could undermine tribal-state gaming compacts and divert gaming revenue from tribal and state governments. Bloomberg reports Kalshi processed $5.1 billion in notional World Cup trading volume, while crypto analysts said Polymarket attracted $1.6 billion in a single week.