diff --git a/mapmaker/flatmap/__init__.py b/mapmaker/flatmap/__init__.py
index f041e186..e0f488fb 100644
--- a/mapmaker/flatmap/__init__.py
+++ b/mapmaker/flatmap/__init__.py
@@ -298,7 +298,7 @@ def new_feature(self, layer_id: str, geometry, properties, is_group=False) -> Op
         self.__last_geojson_id += 1
         feature = Feature(self.__last_geojson_id, geometry, properties, is_group=is_group)
         self.__features_by_geojson_id[feature.geojson_id] = feature
-        if feature.id:
+        if feature.id and (not properties.get('group', False) or is_group):
             self.__features_with_id[feature.id] = feature
         if self.map_kind == MAP_KIND.FUNCTIONAL:
             if (name := properties.get('name', '')) != '':
diff --git a/mapmaker/flatmap/layers.py b/mapmaker/flatmap/layers.py
index fd1ef626..47b839bf 100644
--- a/mapmaker/flatmap/layers.py
+++ b/mapmaker/flatmap/layers.py
@@ -430,15 +430,11 @@ def add_group_features(self, group_name: str, features: list[Feature],
                     feature.geometry = feature.geometry.buffer(0).difference(interior_polygon)
 
         # Construct a MultiPolygon containing all of the group's polygons
-        # But only if the group contains a `.group` element...
-
-        # So that any grouped features don't have duplicate ids
-        grouped_properties.pop('id', None)
+        # But only if the group contained a `.group` element...
         feature_group = None  # Our returned Feature
         if generate_group:
-            grouped_polygon_features = [ feature for feature in features if feature.is_group ]
-            for feature in layer_features:
-                grouped_polygon_features.append(feature)
+            grouped_polygon_features = []
+            grouped_polygon_features.extend(layer_features)
 
             grouped_polygons = []
             for feature in grouped_polygon_features:
diff --git a/mapmaker/sources/svg/__init__.py b/mapmaker/sources/svg/__init__.py
index 0a807418..cbe6093c 100644
--- a/mapmaker/sources/svg/__init__.py
+++ b/mapmaker/sources/svg/__init__.py
@@ -81,6 +81,7 @@
 NON_INHERITED_PROPERTIES = [
     'id',
     'class',
+    'group',
     'markup',
     'models',
     'tooltip',