diff --git a/Domains/0-Core/BisCore.ecschema.xml b/Domains/0-Core/BisCore.ecschema.xml
index 03b2a2423..225f155ba 100644
--- a/Domains/0-Core/BisCore.ecschema.xml
+++ b/Domains/0-Core/BisCore.ecschema.xml
@@ -1081,6 +1081,11 @@
                     <string>Placement</string>
                 </PropertyNames>
             </ReservedPropertyNames>
+            <NotSubclassableInReferencingSchemas xmlns="CoreCustomAttributes.1.0">
+                <Exceptions>
+                    <string>Analytical:AnalyticalElement</string>
+                </Exceptions>
+            </NotSubclassableInReferencingSchemas>
         </ECCustomAttributes>
         <ECNavigationProperty propertyName="Category" relationshipName="GeometricElement3dIsInCategory" direction="forward" description="The bis:SpatialCategory used to categorize this bis:GeometricElement3d">
             <ECCustomAttributes>
@@ -1157,6 +1162,9 @@
     </ECEntityClass>
     <ECEntityClass typeName="SpatialElement" modifier="Abstract" displayLabel="Spatial Element" description="A bis:SpatialElement is a bis:GeometricElement3d that occupies real world space.">
         <BaseClass>GeometricElement3d</BaseClass>
+        <ECCustomAttributes>
+            <NotSubclassableInReferencingSchemas xmlns="CoreCustomAttributes.1.0"/>
+        </ECCustomAttributes>
     </ECEntityClass>
     <ECEntityClass typeName="PhysicalElement" modifier="Abstract" displayLabel="Physical Element" description="A bis:PhysicalElement is spatially located, has mass, and can be 'touched'.">
         <BaseClass>SpatialElement</BaseClass>
@@ -1218,6 +1226,11 @@
                     <string>Placement</string>
                 </PropertyNames>
             </ReservedPropertyNames>
+            <NotSubclassableInReferencingSchemas xmlns="CoreCustomAttributes.1.0">
+                <Exceptions>
+                    <string>RoadRailAlignment:VerticalAlignment</string>
+                </Exceptions>
+            </NotSubclassableInReferencingSchemas>
         </ECCustomAttributes>
         <ECNavigationProperty propertyName="Category" relationshipName="GeometricElement2dIsInCategory" direction="forward" description="The bis:DrawingCategory used to categorize this bis:GeometricElement2d instance.">
             <ECCustomAttributes>