Wall Street-Backed Startup Fuels Jump in Online Loan Trading

A startup backed by Wall Street’s biggest banks is making headway in a push to bring electronic trading to one of the final holdouts.

The market for leveraged loans — a type of risky debt backed by junk-rated companies — has largely sat out of the technological revolutions that revamped other corners of finance over the past few decades, in part because of complex provisions and long-settlement times that made them difficult to trade online.

But Octaura, a fintech company that arose out of a venture between Bank of America Corp. and Citigroup Inc., has been seizing a ...