diff --git a/src/Mod/Part/App/AppPart.cpp b/src/Mod/Part/App/AppPart.cpp
index 4b1de3fbc1..8fe6ca350b 100644
--- a/src/Mod/Part/App/AppPart.cpp
+++ b/src/Mod/Part/App/AppPart.cpp
@@ -406,6 +406,7 @@ PyMOD_INIT_FUNC(Part)
 
     // Geometry types
     Part::GeometryExtension       	::init();
+    Part::GeometryPersistenceExtension	::init();
     Part::GeometryIntExtension    	::init();
     Part::GeometryStringExtension 	::init();
     Part::GeometryBoolExtension   	::init();
diff --git a/src/Mod/Part/App/Geometry.cpp b/src/Mod/Part/App/Geometry.cpp
index 5f764ad0c4..9c3ba11ce2 100644
--- a/src/Mod/Part/App/Geometry.cpp
+++ b/src/Mod/Part/App/Geometry.cpp
@@ -208,12 +208,21 @@ unsigned int Geometry::getMemSize (void) const
 void Geometry::Save(Base::Writer &writer) const
 {
     // We always store an extension array even if empty, so that restoring is consistent.
-    writer.Stream() << writer.ind() << "<GeoExtensions count=\"" << extensions.size() << "\">" << std::endl;
+
+    // Get the number of persistent extensions
+    int counter = 0;
+    for(auto att:extensions) {
+        if(att->isDerivedFrom(Part::GeometryPersistenceExtension::getClassTypeId()))
+            counter++;
+    }
+
+    writer.Stream() << writer.ind() << "<GeoExtensions count=\"" << counter << "\">" << std::endl;
 
     writer.incInd();
 
     for(auto att:extensions) {
-        att->Save(writer);
+        if(att->isDerivedFrom(Part::GeometryPersistenceExtension::getClassTypeId()))
+            std::static_pointer_cast<Part::GeometryPersistenceExtension>(att)->Save(writer);
     }
 
     writer.decInd();
@@ -234,7 +243,7 @@ void Geometry::Restore(Base::XMLReader &reader)
             reader.readElement("GeoExtension");
             const char* TypeName = reader.getAttribute("type");
             Base::Type type = Base::Type::fromName(TypeName);
-            GeometryExtension *newE = (GeometryExtension *)type.createInstance();
+            GeometryPersistenceExtension *newE = (GeometryPersistenceExtension *)type.createInstance();
             newE->Restore(reader);
 
             extensions.push_back(std::shared_ptr<GeometryExtension>(newE));
diff --git a/src/Mod/Part/App/GeometryDefaultExtension.cpp b/src/Mod/Part/App/GeometryDefaultExtension.cpp
index 1a4e79ded0..7e78941a27 100644
--- a/src/Mod/Part/App/GeometryDefaultExtension.cpp
+++ b/src/Mod/Part/App/GeometryDefaultExtension.cpp
@@ -45,12 +45,6 @@ GeometryDefaultExtension<T>::GeometryDefaultExtension(const T& val, std::string
 }
 
 // Persistence implementer
-template <typename T>
-unsigned int GeometryDefaultExtension<T>::getMemSize (void) const
-{
-    return 1;
-}
-
 template <typename T>
 void GeometryDefaultExtension<T>::Save(Base::Writer &writer) const
 {
@@ -114,7 +108,7 @@ namespace Part {
 //typedef Part::GeometryStringExtension<std::string> GeometryStringExtension;
 
 // ---------- GeometryIntExtension ----------
-TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryIntExtension,Part::GeometryExtension)
+TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryIntExtension,Part::GeometryPersistenceExtension)
 
 template <>
 PyObject * GeometryDefaultExtension<long>::getPyObject(void)
@@ -131,7 +125,7 @@ void GeometryDefaultExtension<long>::Restore(Base::XMLReader &reader)
 }
 
 // ---------- GeometryStringExtension ----------
-TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryStringExtension,Part::GeometryExtension)
+TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryStringExtension,Part::GeometryPersistenceExtension)
 
 template <>
 PyObject * GeometryDefaultExtension<std::string>::getPyObject(void)
@@ -140,7 +134,7 @@ PyObject * GeometryDefaultExtension<std::string>::getPyObject(void)
 }
 
 // ---------- GeometryBoolExtension ----------
-TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryBoolExtension,Part::GeometryExtension)
+TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryBoolExtension,Part::GeometryPersistenceExtension)
 
 template <>
 PyObject * GeometryDefaultExtension<bool>::getPyObject(void)
@@ -157,7 +151,7 @@ void GeometryDefaultExtension<bool>::Restore(Base::XMLReader &reader)
 }
 
 // ---------- GeometryDoubleExtension ----------
-TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryDoubleExtension,Part::GeometryExtension)
+TYPESYSTEM_SOURCE_TEMPLATE_T(Part::GeometryDoubleExtension,Part::GeometryPersistenceExtension)
 
 template <>
 PyObject * GeometryDefaultExtension<double>::getPyObject(void)
diff --git a/src/Mod/Part/App/GeometryDefaultExtension.h b/src/Mod/Part/App/GeometryDefaultExtension.h
index 629e133f2b..b4e0817825 100644
--- a/src/Mod/Part/App/GeometryDefaultExtension.h
+++ b/src/Mod/Part/App/GeometryDefaultExtension.h
@@ -30,7 +30,7 @@
 namespace Part {
 
     template <typename T>
-    class PartExport GeometryDefaultExtension: public Part::GeometryExtension
+    class PartExport GeometryDefaultExtension: public Part::GeometryPersistenceExtension
     {
         TYPESYSTEM_HEADER_WITH_OVERRIDE();
     public:
@@ -42,7 +42,6 @@ namespace Part {
         inline const T &getValue() const {return value;};
 
         // Persistence implementer ---------------------
-        virtual unsigned int getMemSize(void) const override;
         virtual void Save(Base::Writer &/*writer*/) const override;
         virtual void Restore(Base::XMLReader &/*reader*/) override;
 
diff --git a/src/Mod/Part/App/GeometryExtension.cpp b/src/Mod/Part/App/GeometryExtension.cpp
index a7f9296441..6177062098 100644
--- a/src/Mod/Part/App/GeometryExtension.cpp
+++ b/src/Mod/Part/App/GeometryExtension.cpp
@@ -31,13 +31,15 @@
 
 using namespace Part;
 
-TYPESYSTEM_SOURCE_ABSTRACT(Part::GeometryExtension,Base::Persistence)
+TYPESYSTEM_SOURCE_ABSTRACT(Part::GeometryExtension,Base::BaseClass)
 
 GeometryExtension::GeometryExtension()
 {
 }
 
-void GeometryExtension::restoreNameAttribute(Base::XMLReader &reader)
+TYPESYSTEM_SOURCE_ABSTRACT(Part::GeometryPersistenceExtension,Part::GeometryExtension)
+
+void GeometryPersistenceExtension::restoreNameAttribute(Base::XMLReader &reader)
 {
     if(reader.hasAttribute("name")) {
         std::string name = reader.getAttribute("name");
diff --git a/src/Mod/Part/App/GeometryExtension.h b/src/Mod/Part/App/GeometryExtension.h
index 552f1239b0..d4541f2595 100644
--- a/src/Mod/Part/App/GeometryExtension.h
+++ b/src/Mod/Part/App/GeometryExtension.h
@@ -32,17 +32,12 @@
 
 namespace Part {
 
-class PartExport GeometryExtension: public Base::Persistence
+class PartExport GeometryExtension: public Base::BaseClass
 {
     TYPESYSTEM_HEADER();
 public:
     virtual ~GeometryExtension() = default;
 
-    // Persistence implementer ---------------------
-    virtual unsigned int getMemSize(void) const = 0;
-    virtual void Save(Base::Writer &/*writer*/) const = 0;
-    virtual void Restore(Base::XMLReader &/*reader*/) = 0;
-
     virtual std::unique_ptr<GeometryExtension> copy(void) const = 0;
 
     virtual PyObject *getPyObject(void) = 0;
@@ -55,12 +50,26 @@ protected:
     GeometryExtension(const GeometryExtension &obj) = default;
     GeometryExtension& operator= (const GeometryExtension &obj) = default;
 
-    void restoreNameAttribute(Base::XMLReader &/*reader*/);
-
 private:
     std::string name;
 };
 
+
+
+class PartExport GeometryPersistenceExtension : public Part::GeometryExtension
+{
+    TYPESYSTEM_HEADER();
+public:
+    virtual ~GeometryPersistenceExtension() = default;
+
+    // Own Persistence implementer - Not Base::Persistence - managed by Part::Geometry
+    virtual void Save(Base::Writer &/*writer*/) const = 0;
+    virtual void Restore(Base::XMLReader &/*reader*/) = 0;
+
+protected:
+    void restoreNameAttribute(Base::XMLReader &/*reader*/);
+};
+
 }
 
 #endif // PART_GEOMETRYEXTENSION_H
diff --git a/src/Mod/Part/App/GeometryMigrationExtension.cpp b/src/Mod/Part/App/GeometryMigrationExtension.cpp
index 70ba98fff8..813e7f059c 100644
--- a/src/Mod/Part/App/GeometryMigrationExtension.cpp
+++ b/src/Mod/Part/App/GeometryMigrationExtension.cpp
@@ -37,23 +37,6 @@ GeometryMigrationExtension::GeometryMigrationExtension():ConstructionState(false
 
 }
 
-
-// Persistence implementer
-unsigned int GeometryMigrationExtension::getMemSize (void) const
-{
-    return sizeof(long int);
-}
-
-void GeometryMigrationExtension::Save(Base::Writer &writer) const
-{
-    (void) writer;
-}
-
-void GeometryMigrationExtension::Restore(Base::XMLReader &reader)
-{
-    (void) reader;
-}
-
 std::unique_ptr<Part::GeometryExtension> GeometryMigrationExtension::copy(void) const
 {
     auto cpy = std::make_unique<GeometryMigrationExtension>();
diff --git a/src/Mod/Part/App/GeometryMigrationExtension.h b/src/Mod/Part/App/GeometryMigrationExtension.h
index 7940ddc11e..28cca0875d 100644
--- a/src/Mod/Part/App/GeometryMigrationExtension.h
+++ b/src/Mod/Part/App/GeometryMigrationExtension.h
@@ -54,11 +54,6 @@ public:
     GeometryMigrationExtension();
     virtual ~GeometryMigrationExtension() override = default;
 
-    // Persistence implementer ---------------------
-    virtual unsigned int getMemSize(void) const override;
-    virtual void Save(Base::Writer &/*writer*/) const override;
-    virtual void Restore(Base::XMLReader &/*reader*/) override;
-
     virtual std::unique_ptr<Part::GeometryExtension> copy(void) const override;
 
     virtual PyObject *getPyObject(void) override;
diff --git a/src/Mod/Sketcher/App/ExternalGeometryExtension.cpp b/src/Mod/Sketcher/App/ExternalGeometryExtension.cpp
index 754f02cc25..5312e6092f 100644
--- a/src/Mod/Sketcher/App/ExternalGeometryExtension.cpp
+++ b/src/Mod/Sketcher/App/ExternalGeometryExtension.cpp
@@ -35,14 +35,9 @@ using namespace Sketcher;
 
 constexpr std::array<const char *, ExternalGeometryExtension::NumFlags> ExternalGeometryExtension::flag2str;
 
-TYPESYSTEM_SOURCE(Sketcher::ExternalGeometryExtension,Part::GeometryExtension)
+TYPESYSTEM_SOURCE(Sketcher::ExternalGeometryExtension,Part::GeometryPersistenceExtension)
 
 // Persistence implementer
-unsigned int ExternalGeometryExtension::getMemSize (void) const
-{
-    return sizeof(long int);
-}
-
 void ExternalGeometryExtension::Save(Base::Writer &writer) const
 {
     writer.Stream() << writer.ind() << "<GeoExtension type=\"" << this->getTypeId().getName();
diff --git a/src/Mod/Sketcher/App/ExternalGeometryExtension.h b/src/Mod/Sketcher/App/ExternalGeometryExtension.h
index 1877579fac..e306d9cb3a 100644
--- a/src/Mod/Sketcher/App/ExternalGeometryExtension.h
+++ b/src/Mod/Sketcher/App/ExternalGeometryExtension.h
@@ -46,7 +46,7 @@ public:
     virtual void setRef(const std::string & ref) = 0;
 };
 
-class SketcherExport ExternalGeometryExtension : public Part::GeometryExtension, private ISketchExternalGeometryExtension
+class SketcherExport ExternalGeometryExtension : public Part::GeometryPersistenceExtension, private ISketchExternalGeometryExtension
 {
     TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
@@ -68,7 +68,6 @@ public:
     virtual ~ExternalGeometryExtension() override = default;
 
     // Persistence implementer ---------------------
-    virtual unsigned int getMemSize(void) const override;
     virtual void Save(Base::Writer &/*writer*/) const override;
     virtual void Restore(Base::XMLReader &/*reader*/) override;
 
diff --git a/src/Mod/Sketcher/App/SketchGeometryExtension.cpp b/src/Mod/Sketcher/App/SketchGeometryExtension.cpp
index f75be5983d..0f42c13c00 100644
--- a/src/Mod/Sketcher/App/SketchGeometryExtension.cpp
+++ b/src/Mod/Sketcher/App/SketchGeometryExtension.cpp
@@ -36,7 +36,7 @@ using namespace Sketcher;
 constexpr std::array<const char *, InternalType::NumInternalGeometryType> SketchGeometryExtension::internaltype2str;
 constexpr std::array<const char *,GeometryMode::NumGeometryMode> SketchGeometryExtension::geometrymode2str;
 
-TYPESYSTEM_SOURCE(Sketcher::SketchGeometryExtension,Part::GeometryExtension)
+TYPESYSTEM_SOURCE(Sketcher::SketchGeometryExtension,Part::GeometryPersistenceExtension)
 
 // scoped within the class, multithread ready
 std::atomic<long> SketchGeometryExtension::_GeometryID;
@@ -52,11 +52,6 @@ SketchGeometryExtension::SketchGeometryExtension(long cid):Id(cid),InternalGeome
 }
 
 // Persistence implementer
-unsigned int SketchGeometryExtension::getMemSize (void) const
-{
-    return sizeof(long int);
-}
-
 void SketchGeometryExtension::Save(Base::Writer &writer) const
 {
     writer.Stream() << writer.ind() << "<GeoExtension type=\"" << this->getTypeId().getName();
diff --git a/src/Mod/Sketcher/App/SketchGeometryExtension.h b/src/Mod/Sketcher/App/SketchGeometryExtension.h
index 68c05b96da..dd49341c0b 100644
--- a/src/Mod/Sketcher/App/SketchGeometryExtension.h
+++ b/src/Mod/Sketcher/App/SketchGeometryExtension.h
@@ -73,7 +73,7 @@ public:
     virtual void setGeometryMode(int flag, bool v=true) = 0;
 };
 
-class SketcherExport SketchGeometryExtension : public Part::GeometryExtension, private ISketchGeometryExtension
+class SketcherExport SketchGeometryExtension : public Part::GeometryPersistenceExtension, private ISketchGeometryExtension
 {
     TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
@@ -83,7 +83,6 @@ public:
     virtual ~SketchGeometryExtension() override = default;
 
     // Persistence implementer ---------------------
-    virtual unsigned int getMemSize(void) const override;
     virtual void Save(Base::Writer &/*writer*/) const override;
     virtual void Restore(Base::XMLReader &/*reader*/) override;
 
diff --git a/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.cpp b/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.cpp
index e11c4db0a5..f4d3ff3b4c 100644
--- a/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.cpp
+++ b/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.cpp
@@ -39,25 +39,6 @@ ViewProviderSketchGeometryExtension::ViewProviderSketchGeometryExtension():Repre
 
 }
 
-
-// Persistence implementer
-unsigned int ViewProviderSketchGeometryExtension::getMemSize (void) const
-{
-    return sizeof(double);
-}
-
-void ViewProviderSketchGeometryExtension::Save(Base::Writer &writer) const
-{
-    (void) writer;
-    // So far only intended for runtime
-}
-
-void ViewProviderSketchGeometryExtension::Restore(Base::XMLReader &reader)
-{
-    (void) reader;
-    // So far only intended for runtime
-}
-
 std::unique_ptr<Part::GeometryExtension> ViewProviderSketchGeometryExtension::copy(void) const
 {
     auto cpy = std::make_unique<ViewProviderSketchGeometryExtension>();
diff --git a/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.h b/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.h
index 21e91a7fd7..6d5edc1b65 100644
--- a/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.h
+++ b/src/Mod/Sketcher/Gui/ViewProviderSketchGeometryExtension.h
@@ -35,11 +35,6 @@ public:
     ViewProviderSketchGeometryExtension();
     virtual ~ViewProviderSketchGeometryExtension() override = default;
 
-    // Persistence implementer ---------------------
-    virtual unsigned int getMemSize(void) const override;
-    virtual void Save(Base::Writer &/*writer*/) const override;
-    virtual void Restore(Base::XMLReader &/*reader*/) override;
-
     virtual std::unique_ptr<Part::GeometryExtension> copy(void) const override;
 
     virtual PyObject *getPyObject(void) override;