diff --git a/metadata/rules/gorule-0000051.md b/metadata/rules/gorule-0000051.md
index ad11be70..9d806a72 100644
--- a/metadata/rules/gorule-0000051.md
+++ b/metadata/rules/gorule-0000051.md
@@ -10,9 +10,10 @@ implementations:
 ---
 Direct annotations to these terms require a value in the Annotation Extension field: 
 
- * 'GO:0008283 cell population proliferation' 
  * 'GO:0005515 protein binding' 
  * 'GO:0005488 binding'
 
 For more information, see the [binding guidelines](http://wiki.geneontology.org/index.php/Binding_Guidelines)
 on the GO wiki.
+
+This rule may be expanded in the future to include other terms such as 'GO:0008283 cell population proliferation'.