Prediction markets are grabbing headlines, but the two biggest names in it, Polymarket and Kalshi, aren't publicly traded.

Faceless avatars chime in with a standard missive. “Gnoise,” they say—a riff on “gm” or “gmorning,” which is internet parlance for greeting a new day. Noise’s fandom seems to be thriving, at least for ...

Robinhood's platform allows investors to buy and sell stocks, options, futures, and cryptocurrencies. The company entered the prediction markets business earlier this year, which contributed to the ...