diff --git a/app/api/views.py b/app/api/views.py
index d081a08c..2599337b 100644
--- a/app/api/views.py
+++ b/app/api/views.py
@@ -219,7 +219,7 @@ class AnnotationList(generics.ListCreateAPIView):
 
 class AnnotationDetail(generics.RetrieveUpdateDestroyAPIView):
     lookup_url_kwarg = 'annotation_id'
-    permission_classes = [IsAuthenticated & (((IsAnnotator | IsAnnotationApprover) & IsOwnAnnotation) | IsProjectAdmin)]
+    permission_classes = [IsAuthenticated & (((IsAnnotator & IsOwnAnnotation) | IsAnnotationApprover)  | IsProjectAdmin)]
     swagger_schema = None
 
     def get_serializer_class(self):