JPMorgan Chase announced a flurry of executive role changes Tuesday that raised new questions about who could succeed CEO Jamie Dimon in the bank's top job.

Jamie Dimon's "hit-by-the-bus" heir, Daniel Pinto, is retiring. The incoming chief operating officer, Jennifer Piepszak, does not want the CEO role.

JPMorgan Chase & Co. on Tuesday named Jennifer Piepszak its new chief operating officer, but the company’s four major department heads remain more likely successors to Chief Executive Jamie Dimon to head up the largest U.