diff --git a/ifex/transformers/rule_translator.py b/ifex/transformers/rule_translator.py
index 976500c..727d113 100644
--- a/ifex/transformers/rule_translator.py
+++ b/ifex/transformers/rule_translator.py
@@ -388,7 +388,7 @@ def transform(mapping_table, input_obj):
             value = transform_value_common(mapping_table, getattr_value(input_obj, input_attr), field_transform)
 
             # Set attribute unless the result was None (or sometimes due to list handling, a *list* of None values)
-            if value != None and (isinstance(value, list) and not all([x == None for x in value])):
+            if value is not None and (not isinstance(value, list) or not all(x is None for x in value)):
                 set_attr(attributes, output_attr, value)
 
             # Mark this attribute as handled