diff --git a/sentry_sdk/integrations/dedupe.py b/sentry_sdk/integrations/dedupe.py
index a115e35292..d797f66a28 100644
--- a/sentry_sdk/integrations/dedupe.py
+++ b/sentry_sdk/integrations/dedupe.py
@@ -35,10 +35,11 @@ def processor(event, hint):
             if exc_info is None:
                 return event
 
-            exc = exc_info[1]
-            if integration._last_seen.get(None) is exc:
+            exc_id = id(exc_info[1])
+            if integration._last_seen.get(None) == exc_id:
                 return None
-            integration._last_seen.set(exc)
+
+            integration._last_seen.set(exc_id)
             return event
 
     @staticmethod