Oaktree Capital Group LLC named Jay Wintrob, the former head of American International Group Inc.’s life insurance business, as its first chief executive officer.

Wintrob will have primary responsibility for developing and managing Oaktree’s business, according to a statement today from the Los Angeles-based money manager.

Bruce Karsh, the firm’s chief investment officer, will become co-chairman with Howard Marks.

Wintrob left AIG after being passed over for the job of president and CEO, a job that went to Peter Hancock.

Oaktree, which oversaw about $91 billion at the end of June, and is the world’s biggest distressed debt firm, sold shares to the public in 2012.

Marks has been urging caution in credit investing since last year.