diff --git a/src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannBase.cs b/src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannBase.cs
index 9ea8a57d9..1b46b05e7 100644
--- a/src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannBase.cs
+++ b/src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannBase.cs
@@ -271,7 +271,7 @@ namespace NzbDrone.Core.Indexers.Cardigann
                 }
             }
 
-            return ApplyFilters(value.Trim(), selector.Filters, variables);
+            return ApplyFilters(value?.Trim(), selector.Filters, variables) ?? null;
         }
 
         protected Dictionary<string, object> GetBaseTemplateVariables()