Jane Street Group LLC and Citadel Securities are on a roll. Revenue at the two mostly electronic market makers grew about 80% in the first half of the year compared with the first six months of 2023, according to Bloomberg News. That’s enough to make traditional Wall Street executives green with envy — but these newcomers aren’t going to eat the old guard’s lunch entirely.

The largest investment banks such as Goldman Sachs Group Inc. and JPMorgan Chase & Co. have spent years developing more complex, higher-margin trading and lending operations that these newer market makers don’t touch. And unless their business models change, they probably never will.