David Marcus may refer to: Mickey Marcus (David Daniel Marcus, 1901–1948), American-Israeli soldier David Marcus (writer) (1924–2009), Irish Jewish editor and writer David A. Marcus (born 1973), American entrepreneur, co-creator of Facebook's Diem David Marcus (equestrian) (born 1980), Canadian Olympic dressage rider David Marcus (Star Trek), a character in Star Trek See also David Markus (born 1973), American government attorney