Career
He was a sawmill worker by profession, and belonged to the Swedish Saw Mill Industry Workers Union (Swedish: Svenska sågverksindustriarbetarförbundet, SSIAF). Lindberg was chairman of the Swedish Trade Union Confederation (Swedish: Landsorganisationen i Sverige, Liaison Office) from 1936-1947. Lindberg was a proponent of cooperation between the Liaison Office and the Swedish Employers Association (Swedish: Svenska arbetsgivareföreningen, SAF), which resulted in the signing of the Saltsjöbaden Agreement in 1938.