diff --git a/src/db/db/dbRegionProcessors.cc b/src/db/db/dbRegionProcessors.cc
index 9ba85b006..63fcdea3b 100644
--- a/src/db/db/dbRegionProcessors.cc
+++ b/src/db/db/dbRegionProcessors.cc
@@ -170,12 +170,45 @@ contour_to_edges (const db::Polygon::contour_type &contour, PolygonToEdgeProcess
     int s1 = db::vprod_sign (*p0 - *pm1, *p1 - *p0);
     int s2 = db::vprod_sign (*p1 - *p0, *p2 - *p1);
 
-    if (mode == PolygonToEdgeProcessor::All ||
-        (mode == PolygonToEdgeProcessor::Convex && s1 < 0 && s2 < 0) ||
-        (mode == PolygonToEdgeProcessor::Concave && s1 > 0 && s2 > 0) ||
-        (mode == PolygonToEdgeProcessor::StepOut && s1 > 0 && s2 < 0) ||
-        (mode == PolygonToEdgeProcessor::StepIn && s1 < 0 && s2 > 0) ||
-        (mode == PolygonToEdgeProcessor::Step && s1 * s2 < 0)) {
+    bool take = true;
+
+    switch (mode) {
+    case PolygonToEdgeProcessor::All:
+    default:
+      break;
+    case PolygonToEdgeProcessor::Convex:
+      take = s1 < 0 && s2 < 0;
+      break;
+    case PolygonToEdgeProcessor::NotConvex:
+      take = ! (s1 < 0 && s2 < 0);
+      break;
+    case PolygonToEdgeProcessor::Concave:
+      take = s1 > 0 && s2 > 0;
+      break;
+    case PolygonToEdgeProcessor::NotConcave:
+      take = ! (s1 > 0 && s2 > 0);
+      break;
+    case PolygonToEdgeProcessor::StepOut:
+      take = s1 > 0 && s2 < 0;
+      break;
+    case PolygonToEdgeProcessor::NotStepOut:
+      take = ! (s1 > 0 && s2 < 0);
+      break;
+    case PolygonToEdgeProcessor::StepIn:
+      take = s1 < 0 && s2 > 0;
+      break;
+    case PolygonToEdgeProcessor::NotStepIn:
+      take = ! (s1 < 0 && s2 > 0);
+      break;
+    case PolygonToEdgeProcessor::Step:
+      take = s1 * s2 < 0;
+      break;
+    case PolygonToEdgeProcessor::NotStep:
+      take = ! (s1 * s2 < 0);
+      break;
+    }
+
+    if (take) {
       result.push_back (db::Edge (*p0, *p1));
     }
 
diff --git a/src/db/db/dbRegionProcessors.h b/src/db/db/dbRegionProcessors.h
index 9cfc96fc5..08553ca25 100644
--- a/src/db/db/dbRegionProcessors.h
+++ b/src/db/db/dbRegionProcessors.h
@@ -293,7 +293,8 @@ class DB_PUBLIC PolygonToEdgeProcessor
   : public db::PolygonToEdgeProcessorBase
 {
 public:
-  enum EdgeMode { All = 0, Convex, Concave, StepIn, StepOut, Step };
+  enum EdgeMode { All = 0, Convex, Concave, StepIn, StepOut, Step,
+                           NotConvex, NotConcave, NotStepIn, NotStepOut, NotStep };
 
   PolygonToEdgeProcessor (EdgeMode mode = All);
 
diff --git a/src/db/db/gsiDeclDbRegion.cc b/src/db/db/gsiDeclDbRegion.cc
index b51b1f4e9..2e16558ed 100644
--- a/src/db/db/gsiDeclDbRegion.cc
+++ b/src/db/db/gsiDeclDbRegion.cc
@@ -3258,17 +3258,32 @@ gsi::Enum<db::PolygonToEdgeProcessor::EdgeMode> decl_EdgeMode ("db", "EdgeMode",
   gsi::enum_const ("Concave", db::PolygonToEdgeProcessor::Concave,
     "@brief Selects only concave edges\n"
   ) +
+  gsi::enum_const ("NotConcave", db::PolygonToEdgeProcessor::NotConcave,
+    "@brief Selects only edges which are not concave\n"
+  ) +
   gsi::enum_const ("Convex", db::PolygonToEdgeProcessor::Convex,
     "@brief Selects only convex edges\n"
   ) +
+  gsi::enum_const ("NotConvex", db::PolygonToEdgeProcessor::NotConvex,
+    "@brief Selects only edges which are not convex\n"
+  ) +
   gsi::enum_const ("Step", db::PolygonToEdgeProcessor::Step,
     "@brief Selects only step edges leading inside or outside\n"
   ) +
+  gsi::enum_const ("NotStep", db::PolygonToEdgeProcessor::NotStep,
+    "@brief Selects only edges which are not steps\n"
+  ) +
   gsi::enum_const ("StepIn", db::PolygonToEdgeProcessor::StepIn,
     "@brief Selects only step edges leading inside\n"
   ) +
+  gsi::enum_const ("NotStepIn", db::PolygonToEdgeProcessor::NotStepIn,
+    "@brief Selects only edges which are not steps leading inside\n"
+  ) +
   gsi::enum_const ("StepOut", db::PolygonToEdgeProcessor::StepOut,
     "@brief Selects only step edges leading outside\n"
+  ) +
+  gsi::enum_const ("NotStepOut", db::PolygonToEdgeProcessor::NotStepOut,
+    "@brief Selects only edges which are not steps leading outside\n"
   ),
   "@brief This class represents the edge mode type for \\Region#edges.\n"
   "\n"
diff --git a/src/drc/drc/built-in-macros/_drc_complex_ops.rb b/src/drc/drc/built-in-macros/_drc_complex_ops.rb
index 9950da2e9..93a659a95 100644
--- a/src/drc/drc/built-in-macros/_drc_complex_ops.rb
+++ b/src/drc/drc/built-in-macros/_drc_complex_ops.rb
@@ -1014,6 +1014,13 @@ CODE
   # out = in.drc(primary.edges(convex))
   # @/code
   #
+  # In addition, "not_.." variants are available which selects edges
+  # not qualifying for the specific mode:
+  #
+  # @code
+  # out = in.drc(primary.edges(not_convex))
+  # @/code
+  #
   # The mode argument is ignored when translating other objects than
   # polygons.
   
diff --git a/src/drc/drc/built-in-macros/_drc_engine.rb b/src/drc/drc/built-in-macros/_drc_engine.rb
index 3714a325b..e7289f3f6 100644
--- a/src/drc/drc/built-in-macros/_drc_engine.rb
+++ b/src/drc/drc/built-in-macros/_drc_engine.rb
@@ -259,22 +259,42 @@ module DRC
       DRCEdgeMode::new(RBA::EdgeMode::Convex)
     end
     
+    def not_convex
+      DRCEdgeMode::new(RBA::EdgeMode::NotConvex)
+    end
+    
     def concave
       DRCEdgeMode::new(RBA::EdgeMode::Concave)
     end
     
+    def not_concave
+      DRCEdgeMode::new(RBA::EdgeMode::NotConcave)
+    end
+    
     def step_in
       DRCEdgeMode::new(RBA::EdgeMode::StepIn)
     end
     
+    def not_step_in
+      DRCEdgeMode::new(RBA::EdgeMode::NotStepIn)
+    end
+    
     def step_out
       DRCEdgeMode::new(RBA::EdgeMode::StepOut)
     end
     
+    def not_step_out
+      DRCEdgeMode::new(RBA::EdgeMode::NotStepOut)
+    end
+    
     def step
       DRCEdgeMode::new(RBA::EdgeMode::Step)
     end
     
+    def not_step
+      DRCEdgeMode::new(RBA::EdgeMode::NotStep)
+    end
+    
     def padding_zero
       DRCDensityPadding::new(:zero)
     end
diff --git a/src/drc/drc/built-in-macros/_drc_layer.rb b/src/drc/drc/built-in-macros/_drc_layer.rb
index 5d0409e2a..fc722810a 100644
--- a/src/drc/drc/built-in-macros/_drc_layer.rb
+++ b/src/drc/drc/built-in-macros/_drc_layer.rb
@@ -3409,7 +3409,14 @@ CODE
     # out = in.edges(convex)
     # @/code
     #
-    # This feature is only available for polygon layers.
+    # In addition, "not_.." variants are available which selects edges
+    # not qualifying for the specific mode:
+    #
+    # @code
+    # out = in.edges(not_convex)
+    # @/code
+    #
+    # The mode argument is only available for polygon layers.
     #
     # The following images show the effect of the mode argument:
     #
diff --git a/testdata/drc/drcSimpleTests_92.drc b/testdata/drc/drcSimpleTests_92.drc
index 5894b4c93..7187fe7aa 100644
--- a/testdata/drc/drcSimpleTests_92.drc
+++ b/testdata/drc/drcSimpleTests_92.drc
@@ -19,6 +19,12 @@ l2.edges(step).output(103, 0)
 l2.edges(step_in).output(104, 0)
 l2.edges(step_out).output(105, 0)
 
+l2.edges(not_convex).output(111, 0)
+l2.edges(not_concave).output(112, 0)
+l2.edges(not_step).output(113, 0)
+l2.edges(not_step_in).output(114, 0)
+l2.edges(not_step_out).output(115, 0)
+
 l2.drc(primary.edges).output(200, 0)
 l2.drc(primary.edges(convex)).output(201, 0)
 l2.drc(primary.edges(concave)).output(202, 0)
@@ -26,4 +32,9 @@ l2.drc(primary.edges(step)).output(203, 0)
 l2.drc(primary.edges(step_in)).output(204, 0)
 l2.drc(primary.edges(step_out)).output(205, 0)
 
+l2.drc(primary.edges(not_convex)).output(211, 0)
+l2.drc(primary.edges(not_concave)).output(212, 0)
+l2.drc(primary.edges(not_step)).output(213, 0)
+l2.drc(primary.edges(not_step_in)).output(214, 0)
+l2.drc(primary.edges(not_step_out)).output(215, 0)
 
diff --git a/testdata/drc/drcSimpleTests_au92.gds b/testdata/drc/drcSimpleTests_au92.gds
index 2ce998226..26068b9b3 100644
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diff --git a/testdata/drc/drcSimpleTests_au92d.gds b/testdata/drc/drcSimpleTests_au92d.gds
index 77d0297d8..775f8f9fa 100644
Binary files a/testdata/drc/drcSimpleTests_au92d.gds and b/testdata/drc/drcSimpleTests_au92d.gds differ