Invesco Funds Group, a Denver fund sponsor, sacked John Kaweske, co-manager of Invesco's Strategic Health Sciences Fund ($563 million in assets) and its flagship Industrial Income Fund ($3.9 billion in assets). Invesco alleged that Kaweske had failed to report some securities trades in his personal accounts, as Invesco and other funds require. The allegations were being investigated by the Securities and Exchange Commission, the Wall Street Journal reported.

Invesco and Kaweske, who differed on many aspects of his firing, agreed that the portfolio manager's actions had not affected Invesco fund shareholders. Kaweske denied any improprieties, and outside observers said the firing was odd because the alleged transgressions were technical in nature.

"Uncertainty is bad as far as investors are concerned," said Kurt Brouwer, principal in Brouwer & Janachowski, a San Francisco investment advisory firm that specializes in mutual funds. "The obvious question this raises is that, from the tone of what (Invesco) said, what happened wasn't a big deal. So why did they fire him? Are they not telling us something, or are they acting precipitously on the basis of fairly minor transgressions? In either case, you have uncertainty."