At least a dozen investment portfolio managers for Morgan Stanley Investment Management on Tuesday were terminated from their posts, Morgan Stanley spokeswoman Connie Kain said.

The performance history of the fired managers played a key role in who went, Kain said. A desire to "increase efficiency" within the investment management firm also factored into the terminations, she said. The dismissals were not related to any one investment product sector or to investigations by regulators, she said, adding that the terminations were in the works prior to the recent arrival of new Morgan Stanley President of Global Services Bill Ennis.

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