David Frederick Horrobin (6 October 1939 – 1 April 2003) was a British-Canadian entrepreneur, medical researcher, author and editor. He is best known as the founder of the biotechnology company Scotia Holdings and as a promoter of evening primrose oil as a medical treatment, Horrobin was founder and editor of the journals Medical Hypotheses and Prostaglandins, Leukotrienes and Essential Fatty Acids, the latter journal (initially titled Prostaglandins and Medicine) co-founded with his then graduate student Morris Karmazyn.