diff --git a/spacy/lang/de/norm_exceptions.py b/spacy/lang/de/norm_exceptions.py
index 4e2a31e35..6116aa9be 100644
--- a/spacy/lang/de/norm_exceptions.py
+++ b/spacy/lang/de/norm_exceptions.py
@@ -14,5 +14,4 @@ _exc = {
 NORM_EXCEPTIONS = {}
 
 for string, norm in _exc.items():
-    NORM_EXCEPTIONS[string] = norm
     NORM_EXCEPTIONS[string.title()] = norm