Zwei-plus-Vier-Vertrag
After the Second World War, the patent office property was seized by the Allied Control Council, including patents, trademarks, and emblems, under Articles II and X of the Allied Control Council Law No. 5, 30 October 1945. Article II of this Act on 31 August 1951 set aside all Allied Control Council Law but in fact this occurred only on 12 September 1990 with the "Treaty on the Final Settlement with Respect to Germany". Until 1951 the seized patents were used by the Allies technologically and economically.