diff --git a/src/generic/splitter.cpp b/src/generic/splitter.cpp
index e358c875de..f1ba90db39 100644
--- a/src/generic/splitter.cpp
+++ b/src/generic/splitter.cpp
@@ -194,6 +194,12 @@ void wxSplitterWindow::SetResizeCursor()
 void wxSplitterWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 {
     wxPaintDC dc(this);
+#ifdef __WXOSX__
+    // as subpanels might have a transparent background we must erase the background
+    // at least on OSX, otherwise traces of the sash will remain 
+    // test with: splitter sample->replace right window
+    dc.Clear();
+#endif
 
     DrawSash(dc);
 }