diff --git a/src/db/db/dbDeepEdgePairs.cc b/src/db/db/dbDeepEdgePairs.cc
index 12d89df30..a0a53cf8f 100644
--- a/src/db/db/dbDeepEdgePairs.cc
+++ b/src/db/db/dbDeepEdgePairs.cc
@@ -173,9 +173,9 @@ static void transform_deep_layer (db::DeepLayer &deep_layer, const Trans &t)
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer.layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ().transformed (t));
+      flat_shapes.insert (iter->edge_pair ().transformed (iter.trans ()).transformed (t));
     }
 
     layout.clear_layer (deep_layer.layer ());
@@ -208,9 +208,9 @@ void DeepEdgePairs::flatten ()
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer ().layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ());
+      flat_shapes.insert (iter->edge_pair ().transformed (iter.trans ()));
     }
 
     layout.clear_layer (deep_layer ().layer ());
diff --git a/src/db/db/dbDeepEdges.cc b/src/db/db/dbDeepEdges.cc
index b2a299a9f..d93bef028 100644
--- a/src/db/db/dbDeepEdges.cc
+++ b/src/db/db/dbDeepEdges.cc
@@ -233,9 +233,9 @@ static void transform_deep_layer (db::DeepLayer &deep_layer, const Trans &t)
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer.layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ().transformed (t));
+      flat_shapes.insert (iter->edge ().transformed (iter.trans ()).transformed (t));
     }
 
     layout.clear_layer (deep_layer.layer ());
@@ -268,9 +268,9 @@ void DeepEdges::flatten ()
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer ().layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ());
+      flat_shapes.insert (iter->edge ().transformed (iter.trans ()));
     }
 
     layout.clear_layer (deep_layer ().layer ());
diff --git a/src/db/db/dbDeepRegion.cc b/src/db/db/dbDeepRegion.cc
index 2d6aa848d..f126e08fd 100644
--- a/src/db/db/dbDeepRegion.cc
+++ b/src/db/db/dbDeepRegion.cc
@@ -242,9 +242,11 @@ static void transform_deep_layer (db::DeepLayer &deep_layer, const Trans &t)
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer.layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ().transformed (t));
+      db::Polygon poly;
+      iter->polygon (poly);
+      flat_shapes.insert (poly.transformed (iter.trans ()).transformed (t));
     }
 
     layout.clear_layer (deep_layer.layer ());
@@ -277,9 +279,11 @@ void DeepRegion::flatten ()
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer ().layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ());
+      db::Polygon poly;
+      iter->polygon (poly);
+      flat_shapes.insert (poly.transformed (iter.trans ()));
     }
 
     layout.clear_layer (deep_layer ().layer ());
diff --git a/src/db/db/dbDeepTexts.cc b/src/db/db/dbDeepTexts.cc
index b46814961..85796f48b 100644
--- a/src/db/db/dbDeepTexts.cc
+++ b/src/db/db/dbDeepTexts.cc
@@ -193,9 +193,11 @@ static void transform_deep_layer (db::DeepLayer &deep_layer, const Trans &t)
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer.layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ().transformed (t));
+      db::Text text;
+      iter->text (text);
+      flat_shapes.insert (text.transformed (iter.trans ()).transformed (t));
     }
 
     layout.clear_layer (deep_layer.layer ());
@@ -228,9 +230,11 @@ void DeepTexts::flatten ()
 
     db::Cell &top_cell = layout.cell (*layout.begin_top_down ());
 
-    db::Shapes flat_shapes;
+    db::Shapes flat_shapes (layout.is_editable ());
     for (db::RecursiveShapeIterator iter (layout, top_cell, deep_layer ().layer ()); !iter.at_end (); ++iter) {
-      flat_shapes.insert (iter->polygon ());
+      db::Text text;
+      iter->text (text);
+      flat_shapes.insert (db::TextRef (text.transformed (iter.trans ()), layout.shape_repository ()));
     }
 
     layout.clear_layer (deep_layer ().layer ());
diff --git a/src/db/db/dbFlatRegion.cc b/src/db/db/dbFlatRegion.cc
index 71e240cd3..516fd8a31 100644
--- a/src/db/db/dbFlatRegion.cc
+++ b/src/db/db/dbFlatRegion.cc
@@ -413,9 +413,14 @@ void
 FlatRegion::do_insert (const db::Polygon &polygon)
 {
   if (polygon.holes () > 0 || polygon.vertices () > 0) {
+
+    bool is_box = (empty () && polygon.is_box ());
+
     mp_polygons->insert (polygon);
-    m_is_merged = false;
+    set_is_merged (is_box);
+
     invalidate_cache ();
+
   }
 }
 
diff --git a/src/db/db/dbMutableTexts.cc b/src/db/db/dbMutableTexts.cc
index 8556fe4db..d8789e591 100644
--- a/src/db/db/dbMutableTexts.cc
+++ b/src/db/db/dbMutableTexts.cc
@@ -50,7 +50,9 @@ void
 MutableTexts::insert (const db::Shape &shape)
 {
   if (shape.is_text ()) {
-    insert (shape.text ());
+    db::Text text;
+    shape.text (text);
+    insert (text);
   }
 }
 
diff --git a/src/db/unit_tests/dbEdgesTests.cc b/src/db/unit_tests/dbEdgesTests.cc
index 15740ccde..543b60704 100644
--- a/src/db/unit_tests/dbEdgesTests.cc
+++ b/src/db/unit_tests/dbEdgesTests.cc
@@ -55,7 +55,7 @@ TEST(1)
   EXPECT_EQ (r.bbox ().to_string (), "(0,0;100,200)");
   EXPECT_EQ (r.transformed (db::Trans (db::Vector (1, 2))).bbox ().to_string (), "(1,2;101,202)");
   EXPECT_EQ (r.empty (), false);
-  EXPECT_EQ (r.is_merged (), true);
+  EXPECT_EQ (r.is_merged (), false);
   EXPECT_EQ (r.begin ().at_end (), false);
 
   db::Edges r1 = r;
diff --git a/testdata/drc/drcSimpleTests_au4.gds b/testdata/drc/drcSimpleTests_au4.gds
index 843f2b33c..6920b9a33 100644
Binary files a/testdata/drc/drcSimpleTests_au4.gds and b/testdata/drc/drcSimpleTests_au4.gds differ
diff --git a/testdata/ruby/dbEdgePairsTest.rb b/testdata/ruby/dbEdgePairsTest.rb
index 021dbb358..5a27c58fa 100644
--- a/testdata/ruby/dbEdgePairsTest.rb
+++ b/testdata/ruby/dbEdgePairsTest.rb
@@ -179,12 +179,11 @@ class DBEdgePairs_TestClass < TestBase
     assert_equal(r.is_deep?, true)
 
     r.flatten
-    assert_equal(r.has_valid_edge_pairs?, true)
-    assert_equal(r[1].to_s, "(0,101;2,103)/(10,111;12,113)")
-    assert_equal(r[100].inspect, "nil")
+    assert_equal(r.has_valid_edge_pairs?, false)
+    assert_equal(r.to_s, "(0,1;2,3)/(10,11;12,13);(0,101;2,103)/(10,111;12,113);(200,101;202,103)/(210,111;212,113)")
     assert_equal(r.bbox.to_s, "(0,1;212,113)")
 
-    assert_equal(r.is_deep?, false)
+    assert_equal(r.is_deep?, true)
 
   end
 
diff --git a/testdata/ruby/dbEdgesTest.rb b/testdata/ruby/dbEdgesTest.rb
index 4c7f29c17..ffc0e0d36 100644
--- a/testdata/ruby/dbEdgesTest.rb
+++ b/testdata/ruby/dbEdgesTest.rb
@@ -81,7 +81,7 @@ class DBEdges_TestClass < TestBase
     assert_equal(r.count, 4)
     assert_equal(r.hier_count, 4)
     assert_equal(r.bbox.to_s, "(10,20;100,200)")
-    assert_equal(r.is_merged?, true)
+    assert_equal(r.is_merged?, false)
 
     assert_equal(r.moved(RBA::Point::new(10, 20)).bbox.to_s, "(20,40;110,220)")
     assert_equal(r.moved(10, 20).bbox.to_s, "(20,40;110,220)")
@@ -615,12 +615,11 @@ class DBEdges_TestClass < TestBase
 
     r.flatten
 
-    assert_equal(r.is_deep?, false)
+    assert_equal(r.is_deep?, true)
 
     assert_equal(r.count, 12)
     assert_equal(r.hier_count, 12)
-    assert_equal(r[1].to_s, "(-10,20;10,20)")
-    assert_equal(r[100].to_s, "")
+    assert_equal(r.to_s, "(-10,-20;-10,20);(-10,20;10,20);(10,20;10,-20);(10,-20;-10,-20);(-10,80;-10,120);(-10,120;10,120);(10,120;10,80);(10,80;-10,80);(190,80;190,120);(190,120;210,120)...")
 
   end
 
diff --git a/testdata/ruby/dbRegionTest.rb b/testdata/ruby/dbRegionTest.rb
index 79985b676..144d5cffd 100644
--- a/testdata/ruby/dbRegionTest.rb
+++ b/testdata/ruby/dbRegionTest.rb
@@ -95,7 +95,7 @@ class DBRegion_TestClass < TestBase
     assert_equal(r.count, 1)
     assert_equal(r.hier_count, 1)
     assert_equal(r.bbox.to_s, "(10,20;100,200)")
-    assert_equal(r.is_merged?, false)
+    assert_equal(r.is_merged?, true)
     
     r = RBA::Region::new(RBA::SimplePolygon::new(RBA::Box::new(10, 20, 100, 200)))
     assert_equal(r.to_s, "(10,20;10,200;100,200;100,20)")
@@ -107,7 +107,7 @@ class DBRegion_TestClass < TestBase
     assert_equal(r.area, 90*180)
     assert_equal(r.perimeter, 2*90+2*180)
     assert_equal(r.perimeter(RBA::Box::new(0, 0, 50, 50)), 30+40)
-    assert_equal(r.is_merged?, false)
+    assert_equal(r.is_merged?, true)
     
     r = RBA::Region::new(RBA::Path::new([ RBA::Point::new(0, 0), RBA::Point::new(100, 0) ], 20))
     assert_equal(r.to_s, "(0,-10;0,10;100,10;100,-10)")
@@ -116,7 +116,7 @@ class DBRegion_TestClass < TestBase
     assert_equal(r.count, 1)
     assert_equal(r.hier_count, 1)
     assert_equal(r.bbox.to_s, "(0,-10;100,10)")
-    assert_equal(r.is_merged?, false)
+    assert_equal(r.is_merged?, true)
     
     r = RBA::Region::new( [
         RBA::Polygon::new(RBA::Box::new(10, 20, 100, 200)),
@@ -1002,7 +1002,7 @@ class DBRegion_TestClass < TestBase
     assert_equal(RBA::Region::new(target.cell("TRANS").shapes(target_li)).to_s, "")
 
     r.flatten
-    assert_equal(r.is_deep?, false)
+    assert_equal(r.is_deep?, true)
     assert_equal(r.area, 53120000)
 
     # force destroy, so the unit tests pass on the next iteration
diff --git a/testdata/ruby/dbTextsTest.rb b/testdata/ruby/dbTextsTest.rb
index bff5640d2..50d7fb8e2 100644
--- a/testdata/ruby/dbTextsTest.rb
+++ b/testdata/ruby/dbTextsTest.rb
@@ -186,12 +186,10 @@ class DBTexts_TestClass < TestBase
     assert_equal(r.is_deep?, true)
 
     r.flatten
-    assert_equal(r.has_valid_texts?, true)
-    assert_equal(r[1].to_s, "('abc',r0 100,-100)")
-    assert_equal(r[100].inspect, "nil")
+    assert_equal(r.to_s, "('abc',r0 100,-200);('abc',r0 100,-100);('abc',r0 300,-100)")
     assert_equal(r.bbox.to_s, "(100,-200;300,-100)")
 
-    assert_equal(r.is_deep?, false)
+    assert_equal(r.is_deep?, true)
 
   end