diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Arr_batched_point_location_traits_2.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Arr_batched_point_location_traits_2.h
index 103f47c670c..208ff208cfc 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Arr_batched_point_location_traits_2.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Arr_batched_point_location_traits_2.h
@@ -42,6 +42,7 @@ public:
 
   typedef typename Base_traits_2::X_monotone_curve_2   Base_x_monotone_curve_2;
   typedef typename Base_traits_2::Point_2              Base_point_2;
+  typedef typename Base_traits_2::Multiplicity         Multiplicity;
 
   typedef typename Base_traits_2::Construct_min_vertex_2
                                                     Base_construct_min_vertex_2;
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_polycurve_basic_traits_2.h b/Arrangement_on_surface_2/include/CGAL/Arr_polycurve_basic_traits_2.h
index fa5475f7e0c..2ddca1a1809 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_polycurve_basic_traits_2.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_polycurve_basic_traits_2.h
@@ -63,6 +63,7 @@ public:
 
   typedef typename Subcurve_traits_2::Point_2              Point_2;
   typedef typename Subcurve_traits_2::X_monotone_curve_2   X_monotone_subcurve_2;
+  typedef typename Subcurve_traits_2::Multiplicity         Multiplicity;
 
   //@}