diff --git a/cms/migrations/0023_auto_20191203_1029.py b/cms/migrations/0023_auto_20191203_1029.py
new file mode 100644
index 00000000000..f4806c84bf1
--- /dev/null
+++ b/cms/migrations/0023_auto_20191203_1029.py
@@ -0,0 +1,20 @@
+# Generated by Django 2.2.6 on 2019-12-03 09:29
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('cms', '0022_auto_20180620_1551'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='pageuser',
+            name='created_by',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='created_users', to=settings.AUTH_USER_MODEL),
+        ),
+    ]
diff --git a/cms/models/permissionmodels.py b/cms/models/permissionmodels.py
index 95d220079fd..11503b84fdf 100644
--- a/cms/models/permissionmodels.py
+++ b/cms/models/permissionmodels.py
@@ -262,7 +262,7 @@ class PageUserManager(UserManager):
 class PageUser(User):
     """Cms specific user data, required for permission system
     """
-    created_by = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="created_users")
+    created_by = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, on_delete=models.SET_NULL, related_name="created_users")
 
     objects = PageUserManager()