diff --git a/src/core/window.c b/src/core/window.c
index 71a4f60fe..2d12d5357 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -8923,8 +8923,8 @@ meta_window_get_description (MetaWindow *window)
 /**
  * meta_window_get_wm_class:
  * @window: a #MetaWindow
- * 
- * Return the current value of the WM_CLASS X property.
+ *
+ * Return the current value of the name part of WM_CLASS X property.
  */
 const char *
 meta_window_get_wm_class (MetaWindow *window)
@@ -8935,6 +8935,21 @@ meta_window_get_wm_class (MetaWindow *window)
   return window->res_class;
 }
 
+/**
+ * meta_window_get_wm_class_instance:
+ * @window: a #MetaWindow
+ *
+ * Return the current value of the instance part of WM_CLASS X property.
+ */
+const char *
+meta_window_get_wm_class_instance (MetaWindow *window)
+{
+  if (!window)
+    return NULL;
+
+  return window->res_name;
+}
+
 /**
  * meta_window_get_compositor_private:
  * @window: a #MetaWindow
diff --git a/src/include/window.h b/src/include/window.h
index c2c21f64e..d14e76e86 100644
--- a/src/include/window.h
+++ b/src/include/window.h
@@ -88,6 +88,7 @@ void     meta_window_activate_with_workspace (MetaWindow    *window,
                                               MetaWorkspace *workspace);
 const char * meta_window_get_description (MetaWindow *window);
 const char * meta_window_get_wm_class (MetaWindow *window);
+const char * meta_window_get_wm_class_instance (MetaWindow *window);
 /* Return whether the window would be showing if we were on its workspace */
 gboolean    meta_window_showing_on_its_workspace (MetaWindow *window);