Federal authorities insist that SAC's guilty plea, combined with the insider trading convictions of more than 80 people, including eight who used to work for Mr. Cohen, serves as a powerful deterrent. But some say that message may travel only so far.
"The SAC affair put more fear into midlevel people than into billionaires," said Erik M. Gordon, a professor at the Stephen M. Ross School of Business at the University of Michigan. "If you are as rich as Cohen, you can survive huge fines and attorney fees and even an industry ban that leaves you managing your own billions. The only thing you fear is jail time."
Jonathan Gasthalter, a spokesman for Mr. Cohen, declined to comment. The firm this year has taken a number of steps to stiffen its compliance procedures and surveillance of traders to ensure that no more improper trading takes place.
It remains to be seen if Point72 will be able to continue its early success, especially if top traders continue to leave and the firm makes no new star hires to replace them.
The two most recent prominent departures are the portfolio managers Shoney Katz and Peter Avellone, who are joining a trading platform at Citadel, the large investment firm led by Kenneth C. Griffin, another billionaire investor. Mr. Katz and Mr. Avellone left Point72 within the last few weeks, said the people briefed on the matter who spoke on condition of anonymity.
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Gabriel Plotkin, one of Mr. Cohen's most successful traders, recently wound down his onetime $1 billion stock portfolio to focus exclusively on raising money for his own hedge fund, which will start next year with up to $200 million in financial backing from Mr. Cohen. Mr. Plotkin seeks to raise up to $1 billion from other investors and intends to staff his new fund with the analysts and junior traders who have worked with him at Mr. Cohen's firm, these same people said.
Point72 has managed to hire just two established traders from the outside so far this year: Scott Braunstein, who came from JPMorgan Chase's asset management division, and Howard Man from Bank of America Merrill Lynch. For Mr. Man, who will be based in the Point72 office in Hong Kong, this is his second go-round working for Mr. Cohen.
Most of the hires at Point72 have been research analysts, many of them relatively junior employees. The firm has brought on about 30 new analysts this year, said a person briefed on the matter. This person, who spoke on condition of anonymity, said Mr. Cohen was looking to hire analysts over more experienced traders because he now preferred to groom his own trading force.
In effect, Mr. Cohen, a minority owner in the New York Mets baseball team, is looking to create his own internal farm team to develop the firm's traders of tomorrow.