Western Germany recognized the border between Poland - the Oder-Neisse line in 1970.
Additionally, while Western Germany recognized the GDR was its own state - starting 1972 - they didn’t recognize its right to exist under international law. The German constitution stated up until the reunification:
The whole German People remains compelled to fulfill the Unity and Freedom of Germany by virtue of its right to free self-determination.
This implied there was only one Germany, in area and population greater than just Western Germany.
Also, German public broadcast used the upper left map for weather reporting up until the 70s, when they switched to the one on the top right without any borders. After the reunification, the bottom one was used:
Additionally, reunified Germany put numerous GDR leaders and a few soldiers on trial for murdering those trying to flee the GDR. However, the courts had to argue with the GDR’s constitution - which fortunately for the courts was quite the self-contradictory document.