diff --git a/include/wx/msw/ole/dataform.h b/include/wx/msw/ole/dataform.h
index 26959099f7..77ebf70e4d 100644
--- a/include/wx/msw/ole/dataform.h
+++ b/include/wx/msw/ole/dataform.h
@@ -33,8 +33,6 @@ public:
 
     wxDataFormat& operator=(NativeFormat format)
         { m_format = format; return *this; }
-    wxDataFormat& operator=(const wxDataFormat& format)
-        { m_format = format.m_format; return *this; }
 
     // default copy ctor/assignment operators ok