diff --git a/src/api/schedule.py b/src/api/schedule.py
index 991605607819aaa35d887c07f5639b8a8667dc78..cf26a3c40645dca72214468a74a38440c28ee055 100644
--- a/src/api/schedule.py
+++ b/src/api/schedule.py
@@ -156,10 +156,6 @@ class ScheduleEncoder(json.JSONEncoder):
             # direct event lookup -> fetch persons via public_speakers
             persons = event.public_speakers
 
-        # TODO remove this workaround once imported speakers are stored as participants
-        if event.additional_data and 'persons' in event.additional_data and len(event.additional_data['persons']) > 0:
-            persons += event.additional_data['persons']
-
         return [self.encode_person(person) for person in persons]
 
     def encode_event(self, event: Event, tz=None):