Citigroup is undergoing a restructuring of its private banking division following the resignation of Ida Liu, who has led the unit for nearly four years. Liu's departure comes after 18 years with the bank, marking a significant change in leadership. Concurrently, the Bank of Montreal (BMO) has dismissed a managing director from its U.S. mortgage-backed bond desk amid a regulatory investigation into misleading marketing practices. This dismissal is part of an ongoing probe by the Securities and Exchange Commission (SEC), which is also linked to a $41 million settlement deal that BMO is finalizing. The changes at both banks reflect broader shifts in their management structures and regulatory challenges they are facing.