West German half-heavyweight judoka became a bronze medal winner at the 1972 München Olympics in his hometown. He lost his semi-final against upcoming Olympic Champion Shota Chochishvili from the Soviet Union. He was later awarded the Silver Bay Leaf, the highest sports award in Germany. In 1969 and 1971 Barth placed fifth at the World Championships. In 1968 he earned a bronze medal at the Europeans, and in 1973 he won his only West German title. Barth reached the 6th Dan. He later became president of the Bavarian Judo Federation. By profession, he was a bank clerk.