diff --git a/Installation/changes.html b/Installation/changes.html
index 8e4ecc704e0..eb827bb799d 100644
--- a/Installation/changes.html
+++ b/Installation/changes.html
@@ -132,6 +132,11 @@ David A. Wheeler's 'SLOCCount'</a>, restricted to the <code>include/CGAL/</code>
   </li>
 </ul>
 
+<h3>3D Minkowski Sum of Polyhedra</h3>
+<ul>
+<li> Fix a memory leak.
+</ul>
+
 <h3>3D Fast Intersection and Distance Computation</h3>
 <ul>
 <li> Update requirements of the concepts <code>AABBTraits</code> and <code>AABBGeomTraits</code> to match the implementation of the package.
diff --git a/Minkowski_sum_3/include/CGAL/Minkowski_sum_3/bipartite_nary_union_sorted_combined.h b/Minkowski_sum_3/include/CGAL/Minkowski_sum_3/bipartite_nary_union_sorted_combined.h
index d9500a27921..4f156d05be8 100644
--- a/Minkowski_sum_3/include/CGAL/Minkowski_sum_3/bipartite_nary_union_sorted_combined.h
+++ b/Minkowski_sum_3/include/CGAL/Minkowski_sum_3/bipartite_nary_union_sorted_combined.h
@@ -220,6 +220,16 @@ bipartite_nary_union_sorted_combined(Nef_polyhedron& N0,
     Ntmp.delegate(Convertor, true);
     CGAL_assertion(Ntmp.is_valid());
     nary_union.add_polyhedron(Ntmp);
+    delete GcG.sphere_map();
+  }
+
+  // clean up the spherical_mapS
+  for(GM_iterator it = GM0.begin(); it != GM0.end(); ++it) {
+    delete it->first.sphere_map();
+  }
+
+  for(GM_iterator it = GM1.begin(); it != GM1.end(); ++it) {
+    delete it->first.sphere_map();
   }
   
   return nary_union.get_union();
diff --git a/Minkowski_sum_3/test/Minkowski_sum_3/gaussian_map_conversion.cpp b/Minkowski_sum_3/test/Minkowski_sum_3/gaussian_map_conversion.cpp
index c20d01fe53d..05754b5608a 100644
--- a/Minkowski_sum_3/test/Minkowski_sum_3/gaussian_map_conversion.cpp
+++ b/Minkowski_sum_3/test/Minkowski_sum_3/gaussian_map_conversion.cpp
@@ -40,6 +40,7 @@ void test_convex_parts(Nef_polyhedron_3& N)
 
       CGAL_assertion(tmp1.is_valid());      
       CGAL_assertion(tmp1.closure().symmetric_difference(tmp0).is_empty());
+      delete G.sphere_map();
     }
   }
 
@@ -60,6 +61,9 @@ void test_convex_parts(Nef_polyhedron_3& N)
       CGAL_assertion(tmp.vertices_begin()->mark());
       CGAL_assertion(!tmp.volumes_begin()->mark());
       CGAL_assertion(tmp.vertices_begin()->point() == vi->point());
+
+      delete G.sphere_map();
+
       std::cerr << "single vertex " << std::endl;
     }
   }
@@ -85,6 +89,8 @@ void test_convex_parts(Nef_polyhedron_3& N)
 		   eci->source()->point() ||
 		   tmp.vertices_begin()->point() ==
 		   eci->twin()->source()->point());
+    delete G.sphere_map();
+
     std::cerr << "single edge " << std::endl;
   }
   
@@ -106,6 +112,8 @@ void test_convex_parts(Nef_polyhedron_3& N)
     CGAL_assertion(!tmp.volumes_begin()->mark());
     CGAL_assertion(tmp.halffacets_begin()->plane() == fci->plane() ||
 		   tmp.halffacets_begin()->plane() == fci->twin()->plane());
+    delete G.sphere_map();
+
     std::cerr << "single facet " << std::endl;
   }
 }
diff --git a/Nef_S2/include/CGAL/Nef_S2/SM_decorator.h b/Nef_S2/include/CGAL/Nef_S2/SM_decorator.h
index 7f418b32a75..e1553a3ef5a 100644
--- a/Nef_S2/include/CGAL/Nef_S2/SM_decorator.h
+++ b/Nef_S2/include/CGAL/Nef_S2/SM_decorator.h
@@ -125,6 +125,9 @@ handles |SVertex_handle|, |SHalfedge_handle|, or
 |SHalfloop_handle|.}*/
 
 protected: 
+  // don't change this into a shared_ptr even if it seems sensible.
+  // minkowski_sum_3 already has a fix in place that deletes the
+  // object psm_ points to.
   Map* psm_;
 
 public: