diff --git a/src/Mod/Part/App/Geometry.cpp b/src/Mod/Part/App/Geometry.cpp
index 4ce511f416..ed4604b29f 100644
--- a/src/Mod/Part/App/Geometry.cpp
+++ b/src/Mod/Part/App/Geometry.cpp
@@ -372,13 +372,20 @@ void Geometry::assignTag(const Part::Geometry * geo)
         throw Base::TypeError("Geometry tag can not be assigned as geometry types do not match.");
 }
 
+void Geometry::copyNonTag(const Part::Geometry * src)
+{
+    this->Construction = src->Construction;
+
+    for(auto & ext: src->extensions)
+        this->extensions.push_back(ext->copy());
+}
+
 Geometry *Geometry::clone(void) const
 {
     Geometry* cpy = this->copy();
     cpy->tag = this->tag;
 
-    for(auto & ext: extensions)
-        cpy->extensions.push_back(ext->copy());
+    // class copy is responsible for copying extensions
 
     return cpy;
 }
@@ -472,7 +479,7 @@ void GeomPoint::setHandle(const Handle(Geom_CartesianPoint)& p)
 Geometry *GeomPoint::copy(void) const
 {
     GeomPoint *newPoint = new GeomPoint(myPoint);
-    newPoint->Construction = this->Construction;
+    newPoint->copyNonTag(this);
     return newPoint;
 }
 
@@ -929,7 +936,7 @@ const Handle(Geom_Geometry)& GeomBezierCurve::handle() const
 Geometry *GeomBezierCurve::copy(void) const
 {
     GeomBezierCurve *newCurve = new GeomBezierCurve(myCurve);
-    newCurve->Construction = this->Construction;
+    newCurve->copyNonTag(this);
     return newCurve;
 }
 
@@ -1118,7 +1125,7 @@ Geometry *GeomBSplineCurve::copy(void) const
 {
     try {
         GeomBSplineCurve *newCurve = new GeomBSplineCurve(myCurve);
-        newCurve->Construction = this->Construction;
+        newCurve->copyNonTag(this);
         return newCurve;
     }
     catch (Standard_Failure& e) {
@@ -1746,7 +1753,7 @@ const Handle(Geom_Geometry)& GeomTrimmedCurve::handle() const
 Geometry *GeomTrimmedCurve::copy(void) const
 {
     GeomTrimmedCurve *newCurve =  new GeomTrimmedCurve(myCurve);
-    newCurve->Construction = this->Construction;
+    newCurve->copyNonTag(this);
     return newCurve;
 }
 
@@ -2033,7 +2040,7 @@ void GeomCircle::setHandle(const Handle(Geom_Circle)& c)
 Geometry *GeomCircle::copy(void) const
 {
     GeomCircle *newCirc = new GeomCircle(myCurve);
-    newCirc->Construction = this->Construction;
+    newCirc->copyNonTag(this);
     return newCirc;
 }
 
@@ -2225,7 +2232,7 @@ Geometry *GeomArcOfCircle::copy(void) const
 {
     GeomArcOfCircle* copy = new GeomArcOfCircle();
     copy->setHandle(this->myCurve);
-    copy->Construction = this->Construction;
+    copy->copyNonTag(this);
     return copy;
 }
 
@@ -2454,7 +2461,7 @@ void GeomEllipse::setHandle(const Handle(Geom_Ellipse) &e)
 Geometry *GeomEllipse::copy(void) const
 {
     GeomEllipse *newEllipse = new GeomEllipse(myCurve);
-    newEllipse->Construction = this->Construction;
+    newEllipse->copyNonTag(this);
     return newEllipse;
 }
 
@@ -2710,7 +2717,7 @@ Geometry *GeomArcOfEllipse::copy(void) const
 {
     GeomArcOfEllipse* copy = new GeomArcOfEllipse();
     copy->setHandle(this->myCurve);
-    copy->Construction = this->Construction;
+    copy->copyNonTag(this);
     return copy;
 }
 
@@ -2979,7 +2986,7 @@ void GeomHyperbola::setHandle(const Handle(Geom_Hyperbola)& c)
 Geometry *GeomHyperbola::copy(void) const
 {
     GeomHyperbola *newHyp = new GeomHyperbola(myCurve);
-    newHyp->Construction = this->Construction;
+    newHyp->copyNonTag(this);
     return newHyp;
 }
 
@@ -3148,7 +3155,7 @@ Geometry *GeomArcOfHyperbola::copy(void) const
 {
     GeomArcOfHyperbola* copy = new GeomArcOfHyperbola();
     copy->setHandle(this->myCurve);
-    copy->Construction = this->Construction;
+    copy->copyNonTag(this);
     return copy;
 }
 
@@ -3407,7 +3414,7 @@ void GeomParabola::setHandle(const Handle(Geom_Parabola)& c)
 Geometry *GeomParabola::copy(void) const
 {
     GeomParabola *newPar = new GeomParabola(myCurve);
-    newPar->Construction = this->Construction;
+    newPar->copyNonTag(this);
     return newPar;
 }
 
@@ -3557,7 +3564,7 @@ Geometry *GeomArcOfParabola::copy(void) const
 {
     GeomArcOfParabola* copy = new GeomArcOfParabola();
     copy->setHandle(this->myCurve);
-    copy->Construction = this->Construction;
+    copy->copyNonTag(this);
     return copy;
 }
 
@@ -3785,7 +3792,7 @@ void GeomLine::setHandle(const Handle(Geom_Line)& l)
 Geometry *GeomLine::copy(void) const
 {
     GeomLine *newLine = new GeomLine(myCurve);
-    newLine->Construction = this->Construction;
+    newLine->copyNonTag(this);
     return newLine;
 }
 
@@ -3883,7 +3890,7 @@ Geometry *GeomLineSegment::copy(void)const
 {
     GeomLineSegment *tempCurve = new GeomLineSegment();
     tempCurve->myCurve = Handle(Geom_TrimmedCurve)::DownCast(myCurve->Copy());
-    tempCurve->Construction = this->Construction;
+    tempCurve->copyNonTag(this);
     return tempCurve;
 }
 
@@ -4029,7 +4036,7 @@ GeomOffsetCurve::~GeomOffsetCurve()
 Geometry *GeomOffsetCurve::copy(void) const
 {
     GeomOffsetCurve *newCurve = new GeomOffsetCurve(myCurve);
-    newCurve->Construction = this->Construction;
+    newCurve->copyNonTag(this);
     return newCurve;
 }
 
@@ -4201,7 +4208,7 @@ void GeomBezierSurface::setHandle(const Handle(Geom_BezierSurface)& b)
 Geometry *GeomBezierSurface::copy(void) const
 {
     GeomBezierSurface *newSurf =  new GeomBezierSurface(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
@@ -4260,7 +4267,7 @@ const Handle(Geom_Geometry)& GeomBSplineSurface::handle() const
 Geometry *GeomBSplineSurface::copy(void) const
 {
     GeomBSplineSurface *newSurf =  new GeomBSplineSurface(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
@@ -4307,7 +4314,7 @@ Geometry *GeomCylinder::copy(void) const
 {
     GeomCylinder *tempCurve = new GeomCylinder();
     tempCurve->mySurface = Handle(Geom_CylindricalSurface)::DownCast(mySurface->Copy());
-    tempCurve->Construction = this->Construction;
+    tempCurve->copyNonTag(this);
     return tempCurve;
 }
 
@@ -4354,7 +4361,7 @@ Geometry *GeomCone::copy(void) const
 {
     GeomCone *tempCurve = new GeomCone();
     tempCurve->mySurface = Handle(Geom_ConicalSurface)::DownCast(mySurface->Copy());
-    tempCurve->Construction = this->Construction;
+    tempCurve->copyNonTag(this);
     return tempCurve;
 }
 
@@ -4401,7 +4408,7 @@ Geometry *GeomToroid::copy(void) const
 {
     GeomToroid *tempCurve = new GeomToroid();
     tempCurve->mySurface = Handle(Geom_ToroidalSurface)::DownCast(mySurface->Copy());
-    tempCurve->Construction = this->Construction;
+    tempCurve->copyNonTag(this);
     return tempCurve;
 }
 
@@ -4448,7 +4455,7 @@ Geometry *GeomSphere::copy(void) const
 {
     GeomSphere *tempCurve = new GeomSphere();
     tempCurve->mySurface = Handle(Geom_SphericalSurface)::DownCast(mySurface->Copy());
-    tempCurve->Construction = this->Construction;
+    tempCurve->copyNonTag(this);
     return tempCurve;
 }
 
@@ -4495,7 +4502,7 @@ Geometry *GeomPlane::copy(void) const
 {
     GeomPlane *tempCurve = new GeomPlane();
     tempCurve->mySurface = Handle(Geom_Plane)::DownCast(mySurface->Copy());
-    tempCurve->Construction = this->Construction;
+    tempCurve->copyNonTag(this);
     return tempCurve;
 }
 
@@ -4544,7 +4551,7 @@ const Handle(Geom_Geometry)& GeomOffsetSurface::handle() const
 Geometry *GeomOffsetSurface::copy(void) const
 {
     GeomOffsetSurface *newSurf = new GeomOffsetSurface(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
@@ -4599,7 +4606,7 @@ const Handle(Geom_Geometry)& GeomPlateSurface::handle() const
 Geometry *GeomPlateSurface::copy(void) const
 {
     GeomPlateSurface *newSurf = new GeomPlateSurface(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
@@ -4654,7 +4661,7 @@ const Handle(Geom_Geometry)& GeomTrimmedSurface::handle() const
 Geometry *GeomTrimmedSurface::copy(void) const
 {
     GeomTrimmedSurface *newSurf = new GeomTrimmedSurface(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
@@ -4703,7 +4710,7 @@ const Handle(Geom_Geometry)& GeomSurfaceOfRevolution::handle() const
 Geometry *GeomSurfaceOfRevolution::copy(void) const
 {
     GeomSurfaceOfRevolution *newSurf = new GeomSurfaceOfRevolution(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
@@ -4752,7 +4759,7 @@ const Handle(Geom_Geometry)& GeomSurfaceOfExtrusion::handle() const
 Geometry *GeomSurfaceOfExtrusion::copy(void) const
 {
     GeomSurfaceOfExtrusion *newSurf = new GeomSurfaceOfExtrusion(mySurface);
-    newSurf->Construction = this->Construction;
+    newSurf->copyNonTag(this);
     return newSurf;
 }
 
diff --git a/src/Mod/Part/App/Geometry.h b/src/Mod/Part/App/Geometry.h
index 611784c018..9ed35a73a2 100644
--- a/src/Mod/Part/App/Geometry.h
+++ b/src/Mod/Part/App/Geometry.h
@@ -124,6 +124,8 @@ protected:
     /// copies the tag from the geometry passed as a parameter to this object
     void assignTag(const Part::Geometry *);
 
+    void copyNonTag(const Part::Geometry *);
+
 protected:
     Geometry();