diff --git a/tabellio/pcfdb/sync.py b/tabellio/pcfdb/sync.py
index 864b28c..f43da91 100644
--- a/tabellio/pcfdb/sync.py
+++ b/tabellio/pcfdb/sync.py
@@ -13,6 +13,7 @@ from Products.CMFCore.WorkflowCore import WorkflowException
 from Products.Five.browser import BrowserView
 from z3c.sqlalchemy import getSAWrapper, createSAWrapper
 from Products.CMFCore.utils import getToolByName
+from zope.annotation.interfaces import IAnnotations
 
 from zope.event import notify
 from zope.lifecycleevent import ObjectAddedEvent, ObjectModifiedEvent
@@ -242,6 +243,9 @@ class SyncFromPcfDbView(BrowserView):
             obj = getattr(folder, code_id)
         except AttributeError:
             return None
+        annotations = IAnnotations(obj)
+        if annotations['tabellio.com_id'] != com_id:
+            return None
         self._commissions[com_id] = obj
         return obj
 
@@ -726,6 +730,9 @@ class SyncFromPcfDbView(BrowserView):
             object.active == (state == 'S_ACTIVE')
             object.code = code
 
+            annotations = IAnnotations(object)
+            annotations['tabellio.com_id'] = com_id
+
             pers_cursor = self.db_connection.cursor()
             pers_cursor.execute('''SELECT t_pershistoline.type, nom, prenom
                                      FROM t_pers JOIN t_pershistoline
@@ -1090,8 +1097,7 @@ class SyncFromPcfDbView(BrowserView):
 
             try:
                 commission_ids = [self.get_commission_intid(x) for x in (curcom or []) if x not in ('001291649,')]
-                commission_ids = [x for x in commission_ids if x]
-                object.commissions = [RelationValue(x) for x in commission_ids]
+                object.commissions = [RelationValue(x) for x in commission_ids if x]
             except AttributeError:
                 pass