diff --git a/src/db/db/dbRegionDelegate.cc b/src/db/db/dbRegionDelegate.cc
index 3f8997967..2ce4e640d 100644
--- a/src/db/db/dbRegionDelegate.cc
+++ b/src/db/db/dbRegionDelegate.cc
@@ -33,7 +33,7 @@ RegionDelegate::RegionDelegate ()
   m_base_verbosity = 30;
   m_report_progress = false;
   m_merged_semantics = true;
-  m_join_properties_on_merge = true;
+  m_join_properties_on_merge = false;
   m_strict_handling = false;
   m_merge_min_coherence = false;
 }
diff --git a/src/db/db/gsiDeclDbRegion.cc b/src/db/db/gsiDeclDbRegion.cc
index b2fcb38d4..1bd93d5d0 100644
--- a/src/db/db/gsiDeclDbRegion.cc
+++ b/src/db/db/gsiDeclDbRegion.cc
@@ -1059,9 +1059,9 @@ static void break_polygons (db::Region *r, size_t max_vertex_count, double max_a
   r->process (db::PolygonBreaker (max_vertex_count, max_area_ratio));
 }
 
-static db::Region &merge_ext1 (db::Region *r, int min_wc, bool jpm)
+static db::Region &merge_ext1 (db::Region *r, int min_wc)
 {
-  r->merge (false, std::max (0, min_wc - 1), jpm);
+  r->merge (false, std::max (0, min_wc - 1));
   return *r;
 }
 
@@ -1071,9 +1071,9 @@ static db::Region &merge_ext2 (db::Region *r, bool min_coherence, int min_wc, bo
   return *r;
 }
 
-static db::Region merged_ext1 (db::Region *r, int min_wc, bool jpm)
+static db::Region merged_ext1 (db::Region *r, int min_wc)
 {
-  return r->merged (false, std::max (0, min_wc - 1), jpm);
+  return r->merged (false, std::max (0, min_wc - 1));
 }
 
 static db::Region merged_ext2 (db::Region *r, bool min_coherence, int min_wc, bool jpm)
@@ -1747,14 +1747,13 @@ Class<db::Region> decl_Region (decl_dbShapeCollection, "db", "Region",
   method ("join_properties_on_merge=", &db::Region::set_join_properties_on_merge, gsi::arg ("f"),
     "@brief Sets a flag indication whether to join properties on merge\n"
     "\n"
-    "When this flag is set to true (the default), properties are joined on 'merge'.\n"
+    "When this flag is set to true, properties are joined on 'merge'.\n"
     "That is: shapes merging into bigger shapes will have their properties joined.\n"
-    "With the flag set to false, 'merge' will not join properties and return merged\n"
+    "With the flag set to false (the default), 'merge' will not join properties and return merged\n"
     "shapes only if the sub-shapes have the same properties - i.e. properties form\n"
     "different classes on merge.\n"
     "\n"
-    "This attribute has been introduced in version 0.30.3. The default has changed from 'don't join properties' to "
-    "'join properties' in that version."
+    "This attribute has been introduced in version 0.30.3."
   ) +
   method ("join_properties_on_merge?", &db::Region::join_properties_on_merge,
     "@brief Gets a flag indication whether to join properties on merge\n"
@@ -2398,13 +2397,13 @@ Class<db::Region> decl_Region (decl_dbShapeCollection, "db", "Region",
     "@return The region after it has been merged (self).\n"
     "\n"
     "Merging removes overlaps and joins touching polygons.\n"
-    "If the region is already merged, this method does nothing\n"
+    "If the region is already merged, this method does nothing.\n"
+    "This method will behave according to the settings of the \\min_coherence and \\join_properties_on_merge attributes."
   ) +
-  method_ext ("merge", &merge_ext1, gsi::arg ("min_wc"), gsi::arg ("join_properties_on_merge", true),
+  method_ext ("merge", &merge_ext1, gsi::arg ("min_wc"),
     "@brief Merge the region with options\n"
     "\n"
     "@param min_wc Overlap selection\n"
-    "@param join_properties_on_merge See below\n"
     "@return The region after it has been merged (self).\n"
     "\n"
     "Merging removes overlaps and joins touching polygons.\n"
@@ -2412,16 +2411,9 @@ Class<db::Region> decl_Region (decl_dbShapeCollection, "db", "Region",
     "polygons overlap. The value specifies the number of polygons that need to overlap. A value of 2 "
     "means that output is only produced if two or more polygons overlap.\n"
     "\n"
-    "The 'join_properties_on_merge' argument indicates how properties should be handled: if true, "
-    "the properties of the constituents are joined and attached to the merged shape. If false, "
-    "only shapes with the same properties are merged - i.e. different properties form shape classes "
-    "that are merged individually.\n"
-    "\n"
-    "This method is equivalent to \"merge(false, min_wc, join_properties_on_merge).\n"
-    "\n"
-    "'join_properties_on_merge' has been added in version 0.30.3."
+    "This method is equivalent to \"merge(false, min_wc, false).\n"
   ) +
-  method_ext ("merge", &merge_ext2, gsi::arg ("min_coherence"), gsi::arg ("min_wc"), gsi::arg ("join_properties_on_merge", true),
+  method_ext ("merge", &merge_ext2, gsi::arg ("min_coherence"), gsi::arg ("min_wc"), gsi::arg ("join_properties_on_merge", false),
     "@brief Merge the region with options\n"
     "\n"
     "@param min_coherence A flag indicating whether the resulting polygons shall have minimum coherence\n"
@@ -2449,24 +2441,24 @@ Class<db::Region> decl_Region (decl_dbShapeCollection, "db", "Region",
     "\n"
     "Merging removes overlaps and joins touching polygons.\n"
     "If the region is already merged, this method does nothing.\n"
+    "This method will behave according to the settings of the \\min_coherence and \\join_properties_on_merge attributes.\n"
     "In contrast to \\merge, this method does not modify the region but returns a merged copy.\n"
   ) +
-  method_ext ("merged", &merged_ext1, gsi::arg ("min_wc"), gsi::arg ("join_properties_on_merge", true),
+  method_ext ("merged", &merged_ext1, gsi::arg ("min_wc"),
     "@brief Returns the merged region (with options)\n"
     "\n"
     "@param min_wc Overlap selection\n"
-    "@param join_properties_on_merge See below\n"
     "@return The region after it has been merged.\n"
     "\n"
     "This version provides one additional options: \"min_wc\" controls whether output is only produced if multiple "
     "polygons overlap. The value specifies the number of polygons that need to overlap. A value of 2 "
     "means that output is only produced if two or more polygons overlap.\n"
     "\n"
-    "This method is equivalent to \"merged(false, min_wc, join_properties_on_merge)\".\n"
+    "This method is equivalent to \"merged(false, min_wc, false)\".\n"
     "\n"
     "In contrast to \\merge, this method does not modify the region but returns a merged copy.\n"
   ) +
-  method_ext ("merged", &merged_ext2, gsi::arg ("min_coherence"), gsi::arg ("min_wc"), gsi::arg ("join_properties_on_merge", true),
+  method_ext ("merged", &merged_ext2, gsi::arg ("min_coherence"), gsi::arg ("min_wc"), gsi::arg ("join_properties_on_merge", false),
     "@brief Returns the merged region (with options)\n"
     "\n"
     "@param min_coherence A flag indicating whether the resulting polygons shall have minimum coherence\n"
diff --git a/src/db/unit_tests/dbDeepRegionTests.cc b/src/db/unit_tests/dbDeepRegionTests.cc
index fd714701f..a5ecd88b7 100644
--- a/src/db/unit_tests/dbDeepRegionTests.cc
+++ b/src/db/unit_tests/dbDeepRegionTests.cc
@@ -2151,6 +2151,8 @@ TEST(40_BoolWithProperties)
   db::RecursiveShapeIterator si1 (ly, top_cell, l1);
   si1.apply_property_translator (db::PropertiesTranslator::make_pass_all ());
   db::Region r1 (si1, dss);
+  EXPECT_EQ (r1.join_properties_on_merge (), false);
+  r1.set_join_properties_on_merge (true);
   EXPECT_EQ (r1.join_properties_on_merge (), true);
   r1.set_join_properties_on_merge (false);
   EXPECT_EQ (r1.join_properties_on_merge (), false);
diff --git a/src/drc/drc/built-in-macros/_drc_layer.rb b/src/drc/drc/built-in-macros/_drc_layer.rb
index bda81aac9..ee8a7ad42 100644
--- a/src/drc/drc/built-in-macros/_drc_layer.rb
+++ b/src/drc/drc/built-in-macros/_drc_layer.rb
@@ -5103,18 +5103,66 @@ CODE
     # Like \merged, but modifies the input and returns a reference to the 
     # new layer.
     
-    def merged(*args)
+    def merged(overlap_count = 1)
       @engine._context("merged") do
         requires_edges_or_region
-        aa = args.collect { |a| @engine._prep_value(a) }
+        aa = [ @engine._prep_value(overlap_count) ]
         DRCLayer::new(@engine, @engine._tcmd(self.data, 0, self.data.class, :merged, *aa))
       end
     end
     
-    def merge(*args)
+    def merge(overlap_count = 1)
       @engine._context("merge") do
         requires_edges_or_region
-        aa = args.collect { |a| @engine._prep_value(a) }
+        aa = [ @engine._prep_value(overlap_count) ]
+        if @engine.is_tiled?
+          # in tiled mode, no modifying versions are available
+          self.data = @engine._tcmd(self.data, 0, self.data.class, :merged, *aa)
+        else
+          @engine._tcmd(self.data, 0, self.data.class, :merge, *aa)
+        end
+        self
+      end
+    end
+    
+    # %DRC%
+    # @name merged_props
+    # @brief Merges and joins properties of the shapes
+    # @synopsis layer.merged_props([overlap_count])
+    #
+    # Returns the merged input. Unlike the plain \merged method, this version
+    # will join properties on merged shapes. Properties with the same name
+    # will be merged by computing the maximum value of the parts.
+    #
+    # For example:
+    # Properties @tt { "A" => 17, "C" => 2.5 } @/tt merged with @tt { "A" => 1, "B" => "a text" } @/tt will give 
+    # @tt { "A" => 17, "B" => "a text", "C" => 2.5 } @/tt.
+    #
+    # The plain \merged method will treat shapes with different properties as
+    # separate entities and will not merge them.
+    #
+    # Currently, this method is available for polygon layers only.
+    
+    # %DRC%
+    # @name merge_props
+    # @brief Merges the layer and joins the properties (modifies the layer)
+    # @synopsis layer.merge_props([overlap_count])
+    #
+    # Like \merged_props, but modifies the input and returns a reference to the 
+    # new layer.
+    
+    def merged_props(overlap_count = 1)
+      @engine._context("merged") do
+        requires_region
+        aa = [ self.data.min_coherence, @engine._prep_value(overlap_count), true ]
+        DRCLayer::new(@engine, @engine._tcmd(self.data, 0, self.data.class, :merged, *aa))
+      end
+    end
+    
+    def merge_props(overlap_count = 1)
+      @engine._context("merge") do
+        requires_region
+        aa = [ self.data.min_coherence, @engine._prep_value(overlap_count), true ]
         if @engine.is_tiled?
           # in tiled mode, no modifying versions are available
           self.data = @engine._tcmd(self.data, 0, self.data.class, :merged, *aa)
diff --git a/src/drc/unit_tests/drcSimpleTests.cc b/src/drc/unit_tests/drcSimpleTests.cc
index c0850edb1..e5c740e76 100644
--- a/src/drc/unit_tests/drcSimpleTests.cc
+++ b/src/drc/unit_tests/drcSimpleTests.cc
@@ -2003,3 +2003,13 @@ TEST(140d_target_modification)
 {
   run_test (_this, "140", true);
 }
+
+TEST(141_merge_properties)
+{
+  run_test (_this, "141", false);
+}
+
+TEST(141d_merge_properties)
+{
+  run_test (_this, "141", true);
+}
diff --git a/testdata/drc/drcSimpleTests_141.drc b/testdata/drc/drcSimpleTests_141.drc
new file mode 100644
index 000000000..89ed7d0f0
--- /dev/null
+++ b/testdata/drc/drcSimpleTests_141.drc
@@ -0,0 +1,24 @@
+
+source $drc_test_source
+target $drc_test_target
+
+if $drc_test_deep
+  deep
+end
+
+l1 = input(1, 0, enable_props)
+
+l1.output(1, 0)
+
+l1.merged_props.output(10, 0)
+
+l1d = l1.dup
+l1d.merge_props
+l1d.output(11, 0)
+
+l1.merged_props(2).output(20, 0)
+
+l1d = l1.dup
+l1d.merge_props(2)
+l1d.output(21, 0)
+
diff --git a/testdata/drc/drcSimpleTests_141.gds b/testdata/drc/drcSimpleTests_141.gds
new file mode 100644
index 000000000..d17af6401
Binary files /dev/null and b/testdata/drc/drcSimpleTests_141.gds differ
diff --git a/testdata/drc/drcSimpleTests_au141.gds b/testdata/drc/drcSimpleTests_au141.gds
new file mode 100644
index 000000000..20af5373e
Binary files /dev/null and b/testdata/drc/drcSimpleTests_au141.gds differ
diff --git a/testdata/drc/drcSimpleTests_au141d.gds b/testdata/drc/drcSimpleTests_au141d.gds
new file mode 100644
index 000000000..76f8373db
Binary files /dev/null and b/testdata/drc/drcSimpleTests_au141d.gds differ
diff --git a/testdata/ruby/dbRegionTest.rb b/testdata/ruby/dbRegionTest.rb
index 761fa65a7..c7ec7d28e 100644
--- a/testdata/ruby/dbRegionTest.rb
+++ b/testdata/ruby/dbRegionTest.rb
@@ -1637,12 +1637,12 @@ class DBRegion_TestClass < TestBase
     s = r.each.collect(&:to_s).join(";")
     assert_equal(s, "(10,20;10,220;110,220;110,20) props={};(0,0;0,200;100,200;100,0) props={1=>one}")
     rr = r.dup
-    rr.join_properties_on_merge = false
-    assert_equal(rr.join_properties_on_merge, false)
+    rr.join_properties_on_merge = true
+    assert_equal(rr.join_properties_on_merge, true)
     s = rr.each_merged.collect(&:to_s).join(";")
-    assert_equal(s, "(10,20;10,220;110,220;110,20) props={};(0,0;0,200;100,200;100,0) props={1=>one}")
-    s = r.each_merged.collect(&:to_s).join(";")
     assert_equal(s, "(0,0;0,200;10,200;10,220;110,220;110,20;100,20;100,0) props={1=>one}")
+    s = r.each_merged.collect(&:to_s).join(";")
+    assert_equal(s, "(10,20;10,220;110,220;110,20) props={};(0,0;0,200;100,200;100,0) props={1=>one}")
 
     r = RBA::Region::new
     r.insert(RBA::BoxWithProperties::new(RBA::Box::new(0, 0, 100, 200), { 1 => "one" }))