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Bill Gross announced on Friday he was leaving Pimco, which he founded in 1971, for Janus. Morningstar reacted late Monday by downgrading Pimco's flagship Total Return Fund to bronze from gold.
Reaction was also swift in the Total Return exchange-traded fund, which saw a total of $546 million in outflows Friday and Monday. The ETF has $3.12 billion in assets, a fraction of the $222 billion Total Return Fund.
Coppa said he still has confidence in the Pimco management team.
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"I don't think that one person has all the ins and outs of this fund or the company itself," he said.
David Mendels, director of planning at Creative Financial Concepts, said he wouldn't be surprised if he's out of Pimco by the end of October.
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"Turmoil is never a good thing, and when you are investing with a fund manager you are hiring a jockey and the jockey's changed. So there is some uncertainly there," he told "Closing Bell."
That said, he's waiting to see how everything unfolds before deciding if he'll stay or go.
"Panic has always been overrated as an investment strategy," Mendels said. "Bill Gross is a smart guy, but he's not the only smart guy there."