The other two managers announced their exit this month.
Timothy E. Parker, manager of the New Era Fund for the past three years, plans to leave Price by the end of September. The natural resources fund, with $4.48 billion in assets, returned an average of 2.62 percent annually over the past three years ended in April, and 12 percent annually over 10 years.
Parker, 38, said he is exploring his options and has no set plans of what he will do post-Price. He said he might remain in the industry or switch fields and go into charity work or teaching. His replacement will be Shawn T. Driscoll, an energy analyst with the fund.
One week after Parker's announcement, Joseph M. Milano, 40, suddenly left the New America Growth Fund he had been managing since 2002. The fund invests in U.S. companies in the fastest-growing sectors.
Milano said he was leaving the firm to pursue other investment management opportunities, most likely on his own, said Price spokesman Brian Lewbart. Milano could not be reached for comment.
Daniel Martino, manager of the Media & Telecommunications Fund, took over for Milano. He also will continue to co-manage his old fund.
The $3.97 billion New America fund had a 9.15 percent average annual return over 10 years, and 13.89 percent so far this year.
Lallos said New America's rating had been gold; it is now under review, given the change in managers.
The New Era Fund, still under Parker's direction, is rated neutral by Morningstar. The manager has a fairly aggressive approach with high turnover of its holdings and long-term results that have been mediocre compared with peers, Lallos said.
Losing a star manager could hurt a company if he or she controlled a significant percentage of a firm's total assets, and most shareholders are institutions, which are sensitive to management changes and more likely to move their money if they don't like the switch, said Jeffrey Hopson, senior analyst with Stifel, Nicolaus & Co. in St. Louis.
But that's not the case with Jenner, who had the highest profile of the three, Hopson said. The Health Sciences Fund has a large number of small investors who are less likely to bolt, and despite the loss of the manager and two analysts, others on the fund's team remain, he said.
According to Price, the Health Sciences Fund gained about $700 million in assets since Jenner's departure, a mix of new money and market appreciation.
Price still has had to make adjustments.
"Clearly, there is going to be an internal reorganization, and they will try to shore up confidence to their investor base," said Jim Kyung-Soo Liew, a finance professor at Johns Hopkins' Carey Business School.
Price might have to do more if the stock market continues to reach new heights, luring more managers to go out on their own, Liew added.
They may try to follow in the footsteps of Jeff Vinik, Liew said. The onetime manager of Fidelity's famed Magellan Fund left in 1996 to launch a successful hedge fund and later bought the Tampa Bay Lightning of the National Hockey League.
Vinik told investors this month that he would be shutting down the hedge fund, taking a break from day-to-day competition in the market to focus instead on hockey.
"That is the American money manager's dream," Liew said.