HomePage | RecentChanges | Preferences You can edit this page right now! It's a free, community project Simon Flexner (1863 - 1946) was a physician, administrator?, and professor? of pathology? at the University of Pennsylvania. He was the first director of the [Rockefeller Institute for Medical Research]? (1901-1935) and a trustee? of the [Rockefeller Foundation]?. He was also a friend and advisor to [John D. Rockefeller, Jr]?.