diff --git a/include/wx/msw/ole/dataform.h b/include/wx/msw/ole/dataform.h
index f66e2923c5..634ab463e0 100644
--- a/include/wx/msw/ole/dataform.h
+++ b/include/wx/msw/ole/dataform.h
@@ -58,7 +58,7 @@ public:
     void SetId(const wxChar *format);
 
     // returns TRUE if the format is one of those defined in wxDataFormatId
-    bool IsStandard() const { return m_format > 0 && m_format < wxDF_MAX; }
+    bool IsStandard() const { return m_format > 0 && m_format < wxDF_PRIVATE; }
 
 private:
     NativeFormat m_format;