diff --git a/src/db/db/dbEdgePairs.cc b/src/db/db/dbEdgePairs.cc
index 0b5cc36d3..de4b3ab24 100644
--- a/src/db/db/dbEdgePairs.cc
+++ b/src/db/db/dbEdgePairs.cc
@@ -107,7 +107,7 @@ void
 EdgePairs::convert_to_deep (const db::DeepLayer &layer)
 {
   tl_assert (mp_delegate->deep () == 0);
-  set_delegate (new db::DeepEdgePairs (layer));
+  set_delegate (copy_data_id (new db::DeepEdgePairs (layer)));
 }
 
 void
diff --git a/src/db/db/dbEdges.cc b/src/db/db/dbEdges.cc
index 1d6b1a72e..f64d23747 100644
--- a/src/db/db/dbEdges.cc
+++ b/src/db/db/dbEdges.cc
@@ -118,7 +118,7 @@ void
 Edges::convert_to_deep (const db::DeepLayer &layer)
 {
   tl_assert (mp_delegate->deep () == 0);
-  set_delegate (new db::DeepEdges (layer));
+  set_delegate (copy_data_id (new db::DeepEdges (layer)));
 }
 
 const db::RecursiveShapeIterator &
diff --git a/src/db/db/dbRegion.cc b/src/db/db/dbRegion.cc
index e4d1e1983..8e40874fd 100644
--- a/src/db/db/dbRegion.cc
+++ b/src/db/db/dbRegion.cc
@@ -136,7 +136,7 @@ void
 Region::convert_to_deep (const db::DeepLayer &layer)
 {
   tl_assert (mp_delegate->deep () == 0);
-  set_delegate (new db::DeepRegion (layer));
+  set_delegate (copy_data_id (new db::DeepRegion (layer)));
 }
 
 void
diff --git a/src/db/db/dbShapeCollection.h b/src/db/db/dbShapeCollection.h
index 7f59715ff..0f48ffef9 100644
--- a/src/db/db/dbShapeCollection.h
+++ b/src/db/db/dbShapeCollection.h
@@ -75,7 +75,12 @@ class DB_PUBLIC ShapeCollectionDelegateBase
   : public tl::UniqueId
 {
 public:
-  ShapeCollectionDelegateBase () { }
+  ShapeCollectionDelegateBase ()
+    : m_data_id (tl::id_of (this))
+  {
+    //  .. nothing yet ..
+  }
+
   virtual ~ShapeCollectionDelegateBase () { }
 
   virtual DeepShapeCollectionDelegateBase *deep () { return 0; }
@@ -88,6 +93,22 @@ public:
       apply_property_translator (db::PropertiesTranslator::make_remove_all ());
     }
   }
+
+  tl::id_type data_id () const
+  {
+    return m_data_id;
+  }
+
+private:
+  friend class ShapeCollection;
+
+  tl::id_type m_data_id;
+
+  //  used for conversion to deep
+  void set_data_id (tl::id_type data_id)
+  {
+    m_data_id = data_id;
+  }
 };
 
 /**
@@ -116,6 +137,14 @@ public:
    *  delivered by "properties_repository".
    */
   void apply_property_translator (const db::PropertiesTranslator &pt);
+
+protected:
+  template <class Delegate>
+  Delegate *copy_data_id (Delegate *dlg)
+  {
+    dlg->set_data_id (get_delegate ()->data_id ());
+    return dlg;
+  }
 };
 
 }
diff --git a/src/db/db/dbTexts.cc b/src/db/db/dbTexts.cc
index 47420fd39..1e15801ed 100644
--- a/src/db/db/dbTexts.cc
+++ b/src/db/db/dbTexts.cc
@@ -103,7 +103,7 @@ void
 Texts::convert_to_deep (const db::DeepLayer &layer)
 {
   tl_assert (mp_delegate->deep () == 0);
-  set_delegate (new db::DeepTexts (layer));
+  set_delegate (copy_data_id (new db::DeepTexts (layer)));
 }
 
 void
diff --git a/src/db/db/gsiDeclDbEdgePairs.cc b/src/db/db/gsiDeclDbEdgePairs.cc
index 0ea5564f0..5a865399a 100644
--- a/src/db/db/gsiDeclDbEdgePairs.cc
+++ b/src/db/db/gsiDeclDbEdgePairs.cc
@@ -630,9 +630,9 @@ static bool is_deep (const db::EdgePairs *ep)
   return dynamic_cast<const db::DeepEdgePairs *> (ep->delegate ()) != 0;
 }
 
-static size_t id (const db::EdgePairs *ep)
+static size_t data_id (const db::EdgePairs *ep)
 {
-  return tl::id_of (ep->delegate ());
+  return ep->delegate ()->data_id ();
 }
 
 static db::EdgePairs filtered (const db::EdgePairs *r, const gsi::EdgePairFilterBase *f)
@@ -1114,7 +1114,7 @@ Class<db::EdgePairs> decl_EdgePairs (decl_dbShapeCollection, "db", "EdgePairs",
     "\n"
     "This method has been added in version 0.26."
   ) +
-  method_ext ("data_id", &id,
+  method_ext ("data_id", &data_id,
     "@brief Returns the data ID (a unique identifier for the underlying data storage)\n"
     "\n"
     "This method has been added in version 0.26."
diff --git a/src/db/db/gsiDeclDbEdges.cc b/src/db/db/gsiDeclDbEdges.cc
index a434a7d60..667878d62 100644
--- a/src/db/db/gsiDeclDbEdges.cc
+++ b/src/db/db/gsiDeclDbEdges.cc
@@ -892,9 +892,9 @@ static db::Edges *new_texts_as_dots2 (const db::RecursiveShapeIterator &si, db::
   return new db::Edges (db::Region (si).texts_as_dots (pat, pattern, dss));
 }
 
-static size_t id (const db::Edges *e)
+static size_t data_id (const db::Edges *e)
 {
-  return tl::id_of (e->delegate ());
+  return e->delegate ()->data_id ();
 }
 
 static std::vector<db::Edges> andnot_with_edges (const db::Edges *r, const db::Edges &other)
@@ -2572,7 +2572,7 @@ Class<db::Edges> decl_Edges (decl_dbShapeCollection, "db", "Edges",
     "\n"
     "This method has been added in version 0.26."
   ) +
-  method_ext ("data_id", &id,
+  method_ext ("data_id", &data_id,
     "@brief Returns the data ID (a unique identifier for the underlying data storage)\n"
     "\n"
     "This method has been added in version 0.26."
diff --git a/src/db/db/gsiDeclDbRegion.cc b/src/db/db/gsiDeclDbRegion.cc
index 528342e4a..de29f6ba7 100644
--- a/src/db/db/gsiDeclDbRegion.cc
+++ b/src/db/db/gsiDeclDbRegion.cc
@@ -1288,9 +1288,9 @@ static bool is_deep (const db::Region *region)
   return dynamic_cast<const db::DeepRegion *> (region->delegate ()) != 0;
 }
 
-static size_t id (const db::Region *r)
+static size_t data_id (const db::Region *r)
 {
-  return tl::id_of (r->delegate ());
+  return r->delegate ()->data_id ();
 }
 
 
@@ -4214,7 +4214,7 @@ Class<db::Region> decl_Region (decl_dbShapeCollection, "db", "Region",
     "\n"
     "This method has been added in version 0.26."
   ) +
-  method_ext ("data_id", &id,
+  method_ext ("data_id", &data_id,
     "@brief Returns the data ID (a unique identifier for the underlying data storage)\n"
     "\n"
     "This method has been added in version 0.26."
diff --git a/src/db/db/gsiDeclDbTexts.cc b/src/db/db/gsiDeclDbTexts.cc
index 22209b412..21f04d888 100644
--- a/src/db/db/gsiDeclDbTexts.cc
+++ b/src/db/db/gsiDeclDbTexts.cc
@@ -477,9 +477,9 @@ static bool is_deep (const db::Texts *t)
   return dynamic_cast<const db::DeepTexts *> (t->delegate ()) != 0;
 }
 
-static size_t id (const db::Texts *t)
+static size_t data_id (const db::Texts *t)
 {
-  return tl::id_of (t->delegate ());
+  return t->delegate ()->data_id ();
 }
 
 static db::Texts filtered (const db::Texts *r, const gsi::TextFilterBase *f)
@@ -686,7 +686,7 @@ Class<db::Texts> decl_Texts (decl_dbShapeCollection, "db", "Texts",
   method_ext ("is_deep?", &is_deep,
     "@brief Returns true if the edge pair collection is a deep (hierarchical) one\n"
   ) +
-  method_ext ("data_id", &id,
+  method_ext ("data_id", &data_id,
     "@brief Returns the data ID (a unique identifier for the underlying data storage)\n"
   ) +
   method ("+|join", &db::Texts::operator+, gsi::arg ("other"),
diff --git a/src/drc/drc/built-in-macros/_drc_netter.rb b/src/drc/drc/built-in-macros/_drc_netter.rb
index e5ec8f0a2..75506aae2 100644
--- a/src/drc/drc/built-in-macros/_drc_netter.rb
+++ b/src/drc/drc/built-in-macros/_drc_netter.rb
@@ -323,7 +323,9 @@ module DRC
     # 
     # If layers are not named, they will be given a name made from the 
     # \name_prefix and an incremental number when the layer is used for the
-    # first time. 
+    # first time. As the default name prefix is "l", you may can name conflicts
+    # with auto-named layers, if you register explicit layer names like "l5". 
+    # Consider changing the name prefix in that case to some prefix you are not using.
     #
     # \name can only be used once on a layer and the layer names must be 
     # unique (not taken by another layer).