Better Markets has filed a 39-page amicus curiae brief in a US court recommending the closure of the Kalshi election prediction market, citing the risk of manipulation by giant whales. Citing Polymarket as an example, the group pointed out that bets by giant whale accounts on Donald Trump to win the election, which can amount to tens of millions of dollars, could cause market prices to deviate from fundamentals and harm the interests of small retail investors. Better Markets also warned that allowing such contracts to trade could undermine election integrity and place undue electoral oversight responsibilities on the Commodity Futures Trading Commission.