diff --git a/code/model/TrackedManyManyList.php b/code/model/TrackedManyManyList.php
index <HASH>..<HASH> 100644
--- a/code/model/TrackedManyManyList.php
+++ b/code/model/TrackedManyManyList.php
@@ -34,7 +34,7 @@ class TrackedManyManyList extends ManyManyList
             if (class_exists($addingToClass)) {
                 $onItem = $addingToClass::get()->byID($addingTo);
                 if ($onItem) {
-                    if ($item && !$item instanceof DataObject) {
+                    if ($item && !($item instanceof DataObject)) {
                         $class = $this->dataClass;
                         $item = $class::get()->byID($item);
                     }
style(TrackedManyManyList): Add brackets around instanceof check