diff --git a/filter-rules.py b/filter-rules.py
index 8693ac6..9b0a0f3 100644
--- a/filter-rules.py
+++ b/filter-rules.py
@@ -288,9 +288,9 @@ def filter_message(self, message):
         return
 
     # junk known spam headers
-    if (get_header('X-Spam-Flag' == 'YES', headers)
-            or int(get_header('X-MS-Exchange-Organization-SCL', headers)) >= 5
-            or get_header('X-Mailgun-List-Address', headers)):
+    if (int(get_header('X-MS-Exchange-Organization-SCL', headers)) >= 5
+            or get_header('X-Mailgun-List-Address', headers)
+            or get_header('X-SFDC-EmailCategory', headers) == 'apimassmail'):
         self._log_result(message, 'junking spam with known header')
         move_message(message, 'Junk Email')
         return