Greg Holden Lippmann is an American hedge fund manager, born in 1968/1969. He is the Chief Investment Officer and Portfolio Manager at LibreMax Capital, which he co-founded. Lippmann is also recognized as a key figure in Michael Lewis' book, 'The Big Short,' where a character based on him, Jared Vennett, was portrayed by Ryan Gosling in the 2015 film adaptation.

Lippmann earned a bachelor's degree in economics from the University of Pennsylvania in 1991.