But these structural changes altered the CEO's job description into more of a client relationship management job, Mr. Storms said, "which is not a bad job, it's important, but it's not what I do."
Another source with knowledge of UBS operations — who declined to be identified — concurred with Mr. Storms' description of the change.
"It was the case that the regional heads wanted to manage their own businesses, but (Mr.) Fraser globalized a lot of things, including IT and finance. The job really became more of head of distribution rather than a CEO's role, and Brian didn't want that," the source said.
Mr. Storms said: "I've been a CEO for a long time. People in the business were telling me that there is a lot of demand in the industry for people with my experience in retail and institutional asset management, as well as wholesale distribution. The reason for leaving is really the move combined with the change in the job description."
Mr. Storms said he has received offers from other money management firms and is considering his options. Mr. Storms became CEO of UBS Global Asset Management, Americas in July 2002. He had been president and chief operating officer following UBS' acquisition of PaineWebber Inc. in November 2000.
Before that, Mr. Storms was president and CEO of PaineWebber's asset management division, Mitchell Hutchins Asset Management Inc., New York.
Mr. Fraser praised Mr. Storms for "turning the attitude around" at UBS. "To be blunt," Mr. Fraser said, Mr. Storms made UBS "more commercial in a much more competitive environment." He also noted that Mr. Storms had developed and nurtured a much-needed wholesale distribution network for retail investors.
He also said he was particularly grateful that Mr. Storms' oversight of regulatory and compliance matters has kept UBS out of recent mutual fund and hedge fund scandals.
Current and former UBS employees, however, say it had become clear that UBS' asset management division could only have one true head — Mr. Fraser.
Mr. Fraser, an Australian, was promoted to CEO from COO in December 2002, and employees said he immediately began to globalize operations and to exert himself as the global CEO on the investment management side of the bank.