diff --git a/atdb/taskdatabase/services/specification/input_validation.py b/atdb/taskdatabase/services/specification/input_validation.py
index 1cc13fce64a49dc994cb25db16cd49bda41cd0aa..9ed544bc230c71890f22523f9c9a43ab39820367 100644
--- a/atdb/taskdatabase/services/specification/input_validation.py
+++ b/atdb/taskdatabase/services/specification/input_validation.py
@@ -28,6 +28,10 @@ def remove_duplicates(data):
     """
     logger.info(f'check_for_duplicates')
 
+    if not data:
+        # tasks without inputs should just return
+        return False,None
+
     recalculate = False
     seen_surls = set()
     unique_inputs = []