He participated in the finals of Danish Chess Championships and reached his best result in 1976, when he shared 2nd-7th place.
In 1971, in Athens Jacob Øst-Hansen participated in 11th World Junior Chess Championship and shared 14th-15th place.
[1] As member of the Vejlby-Risskov SK team, he participated in the 1st official European Chess Club Cup (1976).
The Danish team reached the quarterfinals and lost to one of the winners of the tournament - Burevestnik Moscow (USSR).
Jacob Øst-Hansen played for Denmark in the Chess Olympiads:[2] Jacob Øst-Hansen played for Denmark in the European Team Chess Championships:[3] Jacob Øst-Hansen played for Denmark in the World Student Team Chess Championships:[4] Jacob Øst-Hansen played for Denmark in the Nordic Chess Cup:[5] This biographical article relating to a Danish chess figure is a stub.