Duke Endowment, a Charlotte, N.C. private foundation, outsourced investment management of nearly all of its $3.2 billion in assets to the Duke Management Co., Durham, N.C. Gene Cochrane Jr., president of the Duke Endowment, said in an interview that officials decided to make the change in light of its former CIO, Stephanie Lynch, who left earlier this year. Because of the size of the fund and the complicated asset classes in which it is invested, the fund would have had to invest more in back-office and technology operations, in addition to hiring a new CIO, Mr. Cochrane explained. Our business is making grants, he said. Moving the management of our investments over made the most sense. The Duke Management Co. also runs $7.4 billion for the Duke University endowment and other university assets.