diff --git a/ses-lambda-python/lambda_function.py b/ses-lambda-python/lambda_function.py
index f18f3e6..77bd50b 100644
--- a/ses-lambda-python/lambda_function.py
+++ b/ses-lambda-python/lambda_function.py
@@ -18,6 +18,9 @@ MAILCOW_API_KEY = os.environ.get('MAILCOW_API_KEY')
 def domain_to_bucket(domain):
     return domain.replace('.', '-') + '-emails'
 
+def bucket_to_domain(bucket):
+    return bucket.replace('-emails', '').replace('-', '.')
+
 def get_valid_inboxes():
     url = 'https://mail.email-srvr.com/api/v1/get/mailbox/all'
     headers = {'X-API-Key': MAILCOW_API_KEY}
@@ -69,7 +72,6 @@ def lambda_handler(event, context):
             }
     except Exception as e:
         print(f"Fehler beim Prüfen der Metadaten: {e}")
-        # Fortfahren, falls Metadaten nicht lesbar sind
 
     # Raw-Mail aus S3 holen
     resp = s3.get_object(Bucket=bucket, Key=key)
@@ -90,6 +92,11 @@ def lambda_handler(event, context):
         recipients = to_addrs + cc_addrs + bcc_addrs
         print("Empfänger aus Headern:", recipients)
 
+        # Im S3-Flow nur Empfänger mit passender Domain behalten
+        expected_domain = bucket_to_domain(bucket)
+        recipients = [rcpt for rcpt in recipients if rcpt.lower().split('@')[1] == expected_domain]
+        print(f"Empfänger nach Domain-Filter ({expected_domain}): {recipients}")
+
     if not recipients:
         raise Exception("Keine Empfänger gefunden, Abbruch")
 
@@ -137,7 +144,7 @@ def lambda_handler(event, context):
         print("Metadatum 'processed:true' hinzugefügt.")
     except Exception as e:
         print(f"Fehler beim Schreiben des Metadatums: {e}")
-        raise  # Fehler weiterleiten, um in CloudWatch sichtbar zu bleiben
+        raise
 
     return {
         'statusCode': 200,