Jamie Dimon's top deputy to retire next year as race to lead biggest US bank heats up

1. Jennifer Piepszak becomes COO, exiting CEO race, emphasizing operational focus. 2. Daniel Pinto retires in 2026, affecting succession plans at JPMorgan. 3. CEO contenders include Marianne Lake, Troy Rohrbaugh, and Mary Erdoes. 4. Dimon's long tenure increases scrutiny on succession planning at JPMorgan.