Jimmy Dunne, 53, became head of Sandler O'Neill unexpectedly.
The small Wall Street partnership used to have its headquarters on the 104th floor of the World Trade Center and was among the hardest hit by the attacks of September 11, 2001. The company lost more than a third of its 171 employees and partners, including Herman Sandler, one of the founders, and Chris Quackenbush, who started its investment banking practice.
Mr Dunne, who co-founded Sandler O'Neill in 1988 with the senior management team of Bear Stearns's financial services group, became the engine of Sandler's regeneration into one of Wall Street's leading boutique investment banks for financial institutions.