Background
He was born in Kristiania as a son of rector Niels Johan Hagerup Østbye (1866–1952) and Johanne Elisabeth Mellbye (1873–1962).
He was born in Kristiania as a son of rector Niels Johan Hagerup Østbye (1866–1952) and Johanne Elisabeth Mellbye (1873–1962).
He worked in Ringnes Bryggeri, Lillehammer Bryggeri and Bjølsen Valsemølle at a young age, but took education as a chemical engineer He was hired in Standard Telefon og Kabelfabrik in 1947, and became chief executive officer in 1949. In 1953 he was hired in Norsk Hydro, becoming Director-General (Chief Executive Officer) in 1956.
He stayed in this position until 1966.
After this he was chairman of the board from 1967 to 1970. From 1966 to 1973 he chaired the Norwegian Trade Council, which is now a part of Innovation Norway.
He was also a supervisory council member of Forsikringsaktieselskabet Norden.