Seymour Horace Knox III (March 9, 1926 in Buffalo, New York – May 22, 1996 in Buffalo) was a philanthropist and sports entrepreneur. He owned the Buffalo Sabres of the National Hockey League from their foundation in 1970 to his death in 1996, and served as chairman of the team. He was the grandson of Seymour H. Knox I, the F.W. Woolworth Company co-founder, and son of art enthusiast Seymour H. Knox II.
Along with his brother Northrup R. Knox, he presented an application October 19, 1965 to obtain a National Hockey League expansion team in 1967, but was rebuffed. In 1968, the NHL Board of Governors rejected their agreement to move the Oakland Seals to Buffalo pending league approval. Finally, on December 2, 1969 the league announced its decision to expand to Buffalo and Vancouver for the 1970–71 season.
By 1975, the Sabres were in the Stanley Cup Finals and Knox was named The Hockey News executive of the year. Knox served on the NHL's Board of Governors for 25 years and was a director of the US Hockey Hall of Fame. He was elected to the Hockey Hall of Fame in 1993. Knox was a principal owner of the Buffalo Sabres from their foundation as a National Hockey League franchise in 1970 until his death in 1996. He was inducted into the Hockey Hall of Fame in 1993.