Here's what Vonmazur said on Surplusrifleforum.com:
The later Imperial Artillery NCO is the basis for this pattern, which is the Weimar NCO Saber. The Nazis never did get around to over-decorating the NCO patterns, they stayed plain. This one is most likely 3rd Reich, due to the trade mark of the maker being stamped along the blade, and they style of grips and plating seem to be later than 1918...Good Saber and actually in decent condition still!!!