(Bloomberg) -- The letters are stamped all over the hallways of Chicago’s giant skyscrapers and grand office buildings. DRW, IMC, CME, Cboe.Most Read from BloombergHow Auto Executives Misread the UAW Ahead of Historic StrikeXi’s Missing Defense Chief Opens Door for US Military TalksEurope Is Better Prepared If Trump Wins Again, Germany’s Baerbock SaysMGM Resorts Hackers Broke In After Tricking IT Service DeskThese are some of the derivatives firms that collectively handle trillions of dollars a