Wikipedia
Siemens-Schuckert (or Siemens-Schuckertwerke) was a German electrical engineering company headquartered in Berlin, Erlangen and Nuremberg that was incorporated into the Siemens AG in 1966.
Siemens Schuckert was founded in 1903 when Siemens & Halske acquired Schuckertwerke. Subsequently Siemens & Halske specialized in communications engineering and Siemens-Schuckert in power engineering and pneumatic instrumentation. During World War I Siemens-Schuckert also produced aircraft. It took over manufacturing of the renowned Protos vehicles in 1908.
The Siemens Schuckert logo consisted of an S with a smaller S superimposed on the middle with the smaller S rotated left by 45 degrees. The logo was used into the late 1960s, when both companies merged with the Siemens-Reiniger-Werke AG to form the present-day Siemens AG.