On 26 May 1959, Heusenstamm was granted town rights, thereby sidestepping Offenbach's efforts to absorb the community. Instead, the new town itself expanded by absorbing one of its neighbours, Rembrücken, in 1977 in the course of municipal reform. In 1978, the town bought the estate of Patershausen, the Klosterwald and the Forst Patershausen (both wooded properties) as well as the Forst Heusenstamm (another wooded property) from Rudolf Graf von Schönborn (“Graf” being his noble title, “Count”). The castle the town likewise acquired in 1979 from the Counts of Schönborn, converting it in the year that followed into the Town Hall.