diff --git a/CI/ci-linux-build.sh b/CI/ci-linux-build.sh
index 9cf501a2..48d8173f 100755
--- a/CI/ci-linux-build.sh
+++ b/CI/ci-linux-build.sh
@@ -69,9 +69,9 @@ else
 
   echo "Copying all required libraries of OpenMesh to the systemlib directory"
   if [ "$BUILD_TYPE" == "release" ]; then
-    ldd Build/lib/libOpenMeshCore.so.9.1 | grep "=> /" | awk '{print $3}' | xargs -I '{}' cp -v '{}' systemlib
+    ldd Build/lib/libOpenMeshCore.so.10.0 | grep "=> /" | awk '{print $3}' | xargs -I '{}' cp -v '{}' systemlib
   else
-    ldd Build/lib/libOpenMeshCored.so.9.1 | grep "=> /" | awk '{print $3}' | xargs -I '{}' cp -v '{}' systemlib
+    ldd Build/lib/libOpenMeshCored.so.10.0 | grep "=> /" | awk '{print $3}' | xargs -I '{}' cp -v '{}' systemlib
   fi
 fi
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index aa4cb591..e087cb5b 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,7 +9,7 @@ enable_testing()
 
 
 project (OpenMesh 
-         VERSION 9.1.0
+         VERSION 10.0.0
          LANGUAGES C CXX ) 
 
 # Set AUTO UIC/MOC Policy to new for CMAKE 3.17 or higher
diff --git a/Doc/changelog.docu b/Doc/changelog.docu
index 554d06db..69ef376f 100644
--- a/Doc/changelog.docu
+++ b/Doc/changelog.docu
@@ -8,6 +8,11 @@
 
 <tr valign=top><td><b>10.0</b> (?/?/?)</td><td>
 
+<b>Breaking Changes</b>
+<ul>
+<li>OM Reader/Writer: Only rad and write custom properties if the Custom option is set (The default option contains this flag).</li>
+</ul>
+
 <b>IO</b>
 <ul>
 <li>PLY reader/writer: Support for meshlab texture coordinates and ids in PLY IO (Thanks to  Gregoire Grzeczkowicz for the patch)</li>
diff --git a/README.md b/README.md
index 11155d6f..faf497ee 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# OpenMesh, 9.1
+# OpenMesh, 10.0
 
 [![](https://gitlab.vci.wth-aachen.de:9000/OpenMesh/OpenMesh/badges/master/pipeline.svg)](https://gitlab.vci.rwth-aachen.de:9000/OpenMesh/OpenMesh/commits/master)
 
diff --git a/src/OpenMesh/Core/IO/Options.hh b/src/OpenMesh/Core/IO/Options.hh
index 05461d43..af1e0ed8 100644
--- a/src/OpenMesh/Core/IO/Options.hh
+++ b/src/OpenMesh/Core/IO/Options.hh
@@ -97,7 +97,7 @@ public:
   /// Definitions of %Options for reading and writing. The options can be
   /// or'ed.
   enum Flag {
-      Default        = 0x0000, ///< No options
+      None           = 0x0000, ///< No options
       Binary         = 0x0001, ///< Set binary mode for r/w
       MSB            = 0x0002, ///< Assume big endian byte ordering
       LSB            = 0x0004, ///< Assume little endian byte ordering
@@ -111,9 +111,10 @@ public:
       FaceTexCoord   = 0x0400, ///< Has (r) / store (w) face texture coordinates
       ColorAlpha     = 0x0800, ///< Has (r) / store (w) alpha values for colors
       ColorFloat     = 0x1000, ///< Has (r) / store (w) float values for colors (currently only implemented for PLY and OFF files)
-      Custom         = 0x2000, ///< Has (r)             custom properties (currently only implemented in PLY Reader ASCII version)
+      Custom         = 0x2000, ///< Has (r) / store (w) custom properties marked persistent (currently PLY only supports reading and only ASCII version. OM supports reading and writing)
       Status         = 0x4000, ///< Has (r) / store (w) status properties
-      TexCoordST     = 0x8000  ///< Write texture coordinates as ST instead of UV
+      TexCoordST     = 0x8000, ///< Write texture coordinates as ST instead of UV
+      Default        = Custom, ///< By default write persistent custom properties
   };
 
   /// Texture filename. This will be written as
diff --git a/src/OpenMesh/Core/IO/reader/OMReader.cc b/src/OpenMesh/Core/IO/reader/OMReader.cc
index b9b9cb4d..f782b641 100644
--- a/src/OpenMesh/Core/IO/reader/OMReader.cc
+++ b/src/OpenMesh/Core/IO/reader/OMReader.cc
@@ -406,7 +406,8 @@ bool _OMReader_::read_binary_vertex_chunk(std::istream &_is, BaseImporter &_bi,
       {
         Chunk::PropertyName property_type;
         bytes_ += restore(_is, property_type, _swap);
-        add_generic_property(property_type, _bi);
+        if (_opt.check(Options::Custom))
+          add_generic_property(property_type, _bi);
       }
 
       bytes_ += restore_binary_custom_data(_is, _bi.kernel()->_get_vprop(property_name_), header_.n_vertices_, _swap);
@@ -563,7 +564,8 @@ bool _OMReader_::read_binary_face_chunk(std::istream &_is, BaseImporter &_bi, Op
       {
         Chunk::PropertyName property_type;
         bytes_ += restore(_is, property_type, _swap);
-        add_generic_property(property_type, _bi);
+        if (_opt.check(Options::Custom))
+          add_generic_property(property_type, _bi);
       }
 
       bytes_ += restore_binary_custom_data(_is, _bi.kernel()->_get_fprop(property_name_), header_.n_faces_, _swap);
@@ -604,7 +606,8 @@ bool _OMReader_::read_binary_edge_chunk(std::istream &_is, BaseImporter &_bi, Op
       {
         Chunk::PropertyName property_type;
         bytes_ += restore(_is, property_type, _swap);
-        add_generic_property(property_type, _bi);
+        if (_opt.check(Options::Custom))
+          add_generic_property(property_type, _bi);
       }
 
       bytes_ += restore_binary_custom_data(_is, _bi.kernel()->_get_eprop(property_name_), header_.n_edges_, _swap);
@@ -654,7 +657,8 @@ bool _OMReader_::read_binary_halfedge_chunk(std::istream &_is, BaseImporter &_bi
       {
         Chunk::PropertyName property_type;
         bytes_ += restore(_is, property_type, _swap);
-        add_generic_property(property_type, _bi);
+        if (_opt.check(Options::Custom))
+          add_generic_property(property_type, _bi);
       }
 
       bytes_ += restore_binary_custom_data(_is, _bi.kernel()->_get_hprop(property_name_), 2 * header_.n_edges_, _swap);
@@ -689,7 +693,7 @@ bool _OMReader_::read_binary_halfedge_chunk(std::istream &_is, BaseImporter &_bi
       {
         int next_id_0      = -1;
         int to_vertex_id_0 = -1;
-        int face_id_0      = -1; 
+        int face_id_0      = -1;
         bytes_ += restore( _is, next_id_0,      OMFormat::Chunk::Integer_Size(chunk_header_.bits_), _swap );
         bytes_ += restore( _is, to_vertex_id_0, OMFormat::Chunk::Integer_Size(chunk_header_.bits_), _swap );
         bytes_ += restore( _is, face_id_0,      OMFormat::Chunk::Integer_Size(chunk_header_.bits_), _swap );
@@ -745,7 +749,7 @@ bool _OMReader_::read_binary_halfedge_chunk(std::istream &_is, BaseImporter &_bi
 
 //-----------------------------------------------------------------------------
 
-bool _OMReader_::read_binary_mesh_chunk(std::istream &_is, BaseImporter &_bi, Options & /* _opt */, bool _swap) const
+bool _OMReader_::read_binary_mesh_chunk(std::istream &_is, BaseImporter &_bi, Options& _opt , bool _swap) const
 {
   using OMFormat::Chunk;
 
@@ -760,7 +764,8 @@ bool _OMReader_::read_binary_mesh_chunk(std::istream &_is, BaseImporter &_bi, Op
       {
         Chunk::PropertyName property_type;
         bytes_ += restore(_is, property_type, _swap);
-        add_generic_property(property_type, _bi);
+        if (_opt.check(Options::Custom))
+          add_generic_property(property_type, _bi);
       }
 
       bytes_ += restore_binary_custom_data(_is, _bi.kernel()->_get_mprop(property_name_), 1, _swap);
diff --git a/src/OpenMesh/Core/IO/writer/OMWriter.cc b/src/OpenMesh/Core/IO/writer/OMWriter.cc
index 9526c05a..cfe60603 100644
--- a/src/OpenMesh/Core/IO/writer/OMWriter.cc
+++ b/src/OpenMesh/Core/IO/writer/OMWriter.cc
@@ -562,34 +562,35 @@ bool _OMWriter_::write_binary(std::ostream& _os, BaseExporter& _be,
 
   // -------------------- write custom properties
 
-
-
-  const auto store_property = [this, &_os, swap, &bytes](
-    const BaseKernel::const_prop_iterator _it_begin, 
-    const BaseKernel::const_prop_iterator _it_end, 
-    const OMFormat::Chunk::Entity _ent)
+  if (_opt.check(Options::Custom))
   {
-    for (auto prop = _it_begin; prop != _it_end; ++prop)
+    const auto store_property = [this, &_os, swap, &bytes](
+      const BaseKernel::const_prop_iterator _it_begin,
+      const BaseKernel::const_prop_iterator _it_end,
+      const OMFormat::Chunk::Entity _ent)
     {
-      if (!*prop || (*prop)->name().empty() ||
-          ((*prop)->name().size() > 1 && (*prop)->name()[1] == ':'))
-      { // skip dead and "private" properties (no name or name matches "?:*")
-        continue;
+      for (auto prop = _it_begin; prop != _it_end; ++prop)
+      {
+        if (!*prop || (*prop)->name().empty() ||
+            ((*prop)->name().size() > 1 && (*prop)->name()[1] == ':'))
+        { // skip dead and "private" properties (no name or name matches "?:*")
+          continue;
+        }
+        bytes += store_binary_custom_chunk(_os, **prop, _ent, swap);
       }
-      bytes += store_binary_custom_chunk(_os, **prop, _ent, swap);
-    }
-  };
+    };
 
-  store_property(_be.kernel()->vprops_begin(), _be.kernel()->vprops_end(),
-      OMFormat::Chunk::Entity_Vertex);
-  store_property(_be.kernel()->fprops_begin(), _be.kernel()->fprops_end(),
-      OMFormat::Chunk::Entity_Face);
-  store_property(_be.kernel()->eprops_begin(), _be.kernel()->eprops_end(),
-      OMFormat::Chunk::Entity_Edge);
-  store_property(_be.kernel()->hprops_begin(), _be.kernel()->hprops_end(),
-      OMFormat::Chunk::Entity_Halfedge);
-  store_property(_be.kernel()->mprops_begin(), _be.kernel()->mprops_end(),
-      OMFormat::Chunk::Entity_Mesh);
+    store_property(_be.kernel()->vprops_begin(), _be.kernel()->vprops_end(),
+        OMFormat::Chunk::Entity_Vertex);
+    store_property(_be.kernel()->fprops_begin(), _be.kernel()->fprops_end(),
+        OMFormat::Chunk::Entity_Face);
+    store_property(_be.kernel()->eprops_begin(), _be.kernel()->eprops_end(),
+        OMFormat::Chunk::Entity_Edge);
+    store_property(_be.kernel()->hprops_begin(), _be.kernel()->hprops_end(),
+        OMFormat::Chunk::Entity_Halfedge);
+    store_property(_be.kernel()->mprops_begin(), _be.kernel()->mprops_end(),
+        OMFormat::Chunk::Entity_Mesh);
+  }
 
   memset(&chunk_header, 0, sizeof(chunk_header));
   chunk_header.name_ = false;
diff --git a/src/Unittests/unittests_read_write_OM.cc b/src/Unittests/unittests_read_write_OM.cc
index 6ba3b741..e18e47b0 100644
--- a/src/Unittests/unittests_read_write_OM.cc
+++ b/src/Unittests/unittests_read_write_OM.cc
@@ -365,7 +365,9 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleVertexBoolProperty) {
     mesh.property(prop,v3) = true;
 
     // save
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
     // load
@@ -375,7 +377,7 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleVertexBoolProperty) {
     cmpMesh.add_property(prop,"VBProp");
     cmpMesh.property(prop).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -436,7 +438,9 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleVertexBoolPropertySpaceEquivalent) {
     mesh.property(prop,v9) = true;
 
     // save
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
     // load
@@ -445,7 +449,7 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleVertexBoolPropertySpaceEquivalent) {
     cmpMesh.add_property(prop,"VBProp");
     cmpMesh.property(prop).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -500,7 +504,9 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleTwoVertexBoolProperty) {
     mesh.property(prop2,v3) = false;
 
     // save
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
 
@@ -512,7 +518,7 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleTwoVertexBoolProperty) {
     cmpMesh.add_property(prop2,"VBProp2");
     cmpMesh.property(prop2).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -570,7 +576,9 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleEdgeIntProperty) {
     mesh.property(prop,e3) = value3;
 
     // save
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
     // load
@@ -579,7 +587,7 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleEdgeIntProperty) {
     cmpMesh.add_property(prop,propName);
     cmpMesh.property(prop).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -646,8 +654,9 @@ TEST_F(OpenMeshReadWriteOM, WriteSplitTriangleEdgeIntProperty) {
     mesh.property(prop,e6) = value6;
 
     // save
-    OpenMesh::IO::Options options;
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
     // load
@@ -656,7 +665,7 @@ TEST_F(OpenMeshReadWriteOM, WriteSplitTriangleEdgeIntProperty) {
     cmpMesh.add_property(prop,propName);
     cmpMesh.property(prop).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -929,7 +938,9 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleFaceDoubleProperty) {
     mesh.property(prop,f1) = va1ue1;
 
     // save
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
     // load
@@ -938,7 +949,7 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleFaceDoubleProperty) {
     cmpMesh.add_property(prop,propName);
     cmpMesh.property(prop).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -983,7 +994,9 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleFaceFloatProperty) {
     mesh.property(prop,f1) = va1ue1;
 
     // save
-    bool ok = OpenMesh::IO::write_mesh(mesh,filename);
+    OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+
+    bool ok = OpenMesh::IO::write_mesh(mesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to write "<<filename;
 
 
@@ -992,7 +1005,7 @@ TEST_F(OpenMeshReadWriteOM, WriteTriangleFaceFloatProperty) {
     cmpMesh.add_property(prop,propName);
     cmpMesh.property(prop).set_persistent(true);
 
-    ok = OpenMesh::IO::read_mesh(cmpMesh,filename);
+    ok = OpenMesh::IO::read_mesh(cmpMesh, filename, opts);
     EXPECT_TRUE(ok) << "Unable to read "<<filename;
 
     // compare
@@ -1050,7 +1063,8 @@ TEST_F(OpenMeshReadWriteOM, ReadBigMeshWithCustomProperty) {
   mesh.add_property(vertexProp, "IVProp");
   mesh.property(vertexProp).set_persistent(true);
 
-  ok = OpenMesh::IO::read_mesh(mesh,"cube1_customProps.om");
+  OpenMesh::IO::Options opts = OpenMesh::IO::Options::Custom;
+  ok = OpenMesh::IO::read_mesh(mesh,"cube1_customProps.om", opts);
   EXPECT_TRUE(ok) << "Unable to read cube1_customProps.om";
 
   ///=============== result ======================
@@ -1066,7 +1080,7 @@ TEST_F(OpenMeshReadWriteOM, ReadBigMeshWithCustomProperty) {
   wrong = false;
   for (Mesh::VertexIter vIter = mesh.vertices_begin(); vIter != mesh.vertices_end() && !wrong; ++vIter)
     wrong = (vIter->idx() != mesh.property(vertexProp,*vIter));
-  EXPECT_FALSE(wrong) << "min one vertex has worng vertex property";
+  EXPECT_FALSE(wrong) << "min one vertex has wrong vertex property";
 }
 
 
diff --git a/src/Unittests/unittests_tutorials.cc b/src/Unittests/unittests_tutorials.cc
index 01881b0f..fab485ac 100644
--- a/src/Unittests/unittests_tutorials.cc
+++ b/src/Unittests/unittests_tutorials.cc
@@ -781,14 +781,15 @@ TEST_F(OpenMeshTutorials, storing_custom_properties) {
   EXPECT_TRUE(mesh.mproperty(mprop_map).persistent()) << "property should be persistent";
 
   // write mesh
-  bool ok = OpenMesh::IO::write_mesh( mesh, "persistence-check.om" );
+  OpenMesh::IO::Options opts(OpenMesh::IO::Options::Custom);
+  bool ok = OpenMesh::IO::write_mesh(mesh, "persistence-check.om", opts);
   EXPECT_TRUE(ok) << "Cannot write mesh to file 'persistent-check.om'";
 
   // clear mesh
   mesh.clear();
 
   //Read back mesh
-  ok = OpenMesh::IO::read_mesh( mesh, "persistence-check.om" );
+  ok = OpenMesh::IO::read_mesh(mesh, "persistence-check.om", opts);
   EXPECT_TRUE(ok) << "Cannot read mesh from file 'persistence-check.om'";
 
   // check props