Index: trunk/data/validator/combinations.mapcss
===================================================================
--- trunk/data/validator/combinations.mapcss	(revision 11074)
+++ trunk/data/validator/combinations.mapcss	(revision 11080)
@@ -424,2 +424,11 @@
   suggestAlternative: "surface=sand";
 }
+
+/* #13705 */
+relation[type=multipolygon][building] > way {
+  set part_of_building_MP;
+}
+way["addr:housenumber"][!building][!"building:part"][!"demolished:building"][!note][!amenity][!leisure][!landuse][!man_made][!tourism][!barrier]!.part_of_building_MP {
+  /* don't exclude shop because a lot of real missing bulding tag cases have a shop tag. */
+  throwOther: tr("Suspicious object: possibly missing {0} tag.", "{1.key}");
+}