diff --git a/src/inventory_wars/scoring.py b/src/inventory_wars/scoring.py
index f58d56b..88a10c9 100644
--- a/src/inventory_wars/scoring.py
+++ b/src/inventory_wars/scoring.py
@@ -42,8 +42,10 @@ class HighestAmount(Scoring):
         return 0
 
     def calculate_end_score(self) -> ItemShare | None:
-        self.max.score = 1
-        return self.max
+        if self.max:
+            self.max.score = 1
+            return self.max
+        return None
 
 
 class FirstThenHighest(Scoring):