diff --git a/datagateway_api/common/icat/filters.py b/datagateway_api/common/icat/filters.py
index 811a67c8..6d9ad19c 100644
--- a/datagateway_api/common/icat/filters.py
+++ b/datagateway_api/common/icat/filters.py
@@ -164,8 +164,7 @@ def apply_filter(self, query):
             log.info("Adding order filter (for %s)", self.field)
             query.setOrder(PythonICATOrderFilter.result_order)
         except ValueError as e:
-            # Typically either invalid attribute(s) or attribute(s) contains 1-many
-            # relationship
+            # Typically invalid attribute(s)
             raise FilterError(e)
 
         split_fields = self.field.split(".")