Bernard A. Coyne is one of only 17 individuals in medical history to have stood 8 feet tall or more. Coyne may have reached a height of 8 feet 4 inches tall at the time of his death in 1921. His World War I draft registration card, dated 29 August 1918, lists his height as 8 feet. The Guinness Book of World Records stated that he was refused induction into the Army when he stood at a height of 7 feet 9 inches.
Source: Wikipedia