diff --git a/src/blenderbim/blenderbim/bim/module/search/operator.py b/src/blenderbim/blenderbim/bim/module/search/operator.py
index a1d8af4434..8deaecd224 100644
--- a/src/blenderbim/blenderbim/bim/module/search/operator.py
+++ b/src/blenderbim/blenderbim/bim/module/search/operator.py
@@ -470,7 +470,6 @@ class ActivateIfcBuildingStoreyFilter(Operator):
         row.operator("bim.toggle_filter_selection", text="Select All").action = "SELECT"
         row.operator("bim.toggle_filter_selection", text="Deselect All").action = "DESELECT"
 
-
 class UnhideAllElements(Operator):
     """Filter model elements based on selection"""
 
@@ -669,9 +668,8 @@ class AddToIfcGroup(Operator):
         
         group = ifcopenshell.api.run("group.add_group", self.file, **{"Name": self.group_name})
         objects = Selector.parse(self.file, selector_query_syntax)
-        for obj in objects:
-            ifcopenshell.api.run("group.assign_group", self.file, **{"product": obj, "group": group})
-        
+
+        ifcopenshell.api.run("group.assign_group", self.file, **{"product": objects, "group": group})
         Data.load(IfcStore.get_file())
         
         return {"FINISHED"}
diff --git a/src/blenderbim/test/bim/feature/search.feature b/src/blenderbim/test/bim/feature/search.feature
new file mode 100644
index 0000000000..76217d6f98
--- /dev/null
+++ b/src/blenderbim/test/bim/feature/search.feature
@@ -0,0 +1,16 @@
+@root
+Feature: Search
+
+Scenario: Select all walls
+    Given an empty IFC project
+    And I add a cube
+    When the object "Cube" is selected
+    And I set "scene.BIMRootProperties.ifc_class" to "IfcWall"
+    And I press "bim.assign_class"
+    And I add a new group to IfcSelector
+    And I add a new query to IfcSelector
+    And I set "scene.IfcSelectorProperties.groups[0].queries[0].active_option" to "IFC Class"
+    And I set "scene.IfcSelectorProperties.groups[0].queries[0].active_option" to "124: IfcWall"
+    And I press 'bim.filter_model_elements'
+    Then bpy.context.selected_objects should contain "Cube"
+
diff --git a/src/blenderbim/test/bim/test_feature.py b/src/blenderbim/test/bim/test_feature.py
index 4cd6dbcd5a..b56785404a 100644
--- a/src/blenderbim/test/bim/test_feature.py
+++ b/src/blenderbim/test/bim/test_feature.py
@@ -98,6 +98,15 @@ def i_add_a_sun():
 def i_add_a_material():
     bpy.context.active_object.active_material = bpy.data.materials.new("Material")
 
+@given("I add a new group to IfcSelector")
+@when("I add a new group to IfcSelector")
+def i_add_a_new_collection_item():
+    bpy.data.scenes["Scene"].IfcSelectorProperties.groups.add()
+    
+@given("I add a new query to IfcSelector")
+@when("I add a new query to IfcSelector")
+def i_add_a_new_collection_item():
+    bpy.data.scenes["Scene"].IfcSelectorProperties.groups[0].queries.add()
 
 @given(parsers.parse('the material "{name}" colour is set to "{colour}"'))
 @when(parsers.parse('the material "{name}" colour is set to "{colour}"'))
diff --git a/src/ifcopenshell-python/ifcopenshell/api/group/assign_group.py b/src/ifcopenshell-python/ifcopenshell/api/group/assign_group.py
index b8cdea2d9f..ed252a1878 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/group/assign_group.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/group/assign_group.py
@@ -37,7 +37,7 @@ class Usecase:
                 **{
                     "GlobalId": ifcopenshell.guid.new(),
                     "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
-                    "RelatedObjects": [self.settings["product"]],
+                    "RelatedObjects": self.settings["product"],
                     "RelatingGroup": self.settings["group"],
                 }
             )