diff --git a/scipost/constants.py b/scipost/constants.py
index 7a37244c270c6ec72a85cc3312c5695332e9cc8f..30565b7314c13104136891ffca8981cfd41d6be7 100644
--- a/scipost/constants.py
+++ b/scipost/constants.py
@@ -1,5 +1,3 @@
-
-
 DISCIPLINE_PHYSICS = 'physics'
 DISCIPLINE_ASTROPHYSICS = 'astrophysics'
 DISCIPLINE_MATH = 'mathematics'
diff --git a/submissions/constants.py b/submissions/constants.py
index 6fa524e42eafdb888dbf6aa8d1c8ff3f847a6149..9397b022313597a5b36e7a8ddc87e661b4be65d0 100644
--- a/submissions/constants.py
+++ b/submissions/constants.py
@@ -208,3 +208,12 @@ SUBMISSION_CYCLES = (
     (CYCLE_SHORT, 'Short cycle'),
     (CYCLE_DIRECT_REC, 'Direct editorial recommendation'),
 )
+
+EVENT_GENERAL = 'gen'
+EVENT_FOR_EIC = 'eic'
+EVENT_FOR_AUTHOR = 'auth'
+EVENT_TYPES = (
+    (EVENT_GENERAL, 'General comment'),
+    (EVENT_FOR_EIC, 'Comment for Editor-in-charge'),
+    (EVENT_FOR_AUTHOR, 'Comment for author'),
+)
diff --git a/submissions/managers.py b/submissions/managers.py
index 4af4e221c2c9c30bbc3a861bdf5b166c1538aa39..878269b0fa6c2f035ee41b3e7e24658f75625f2f 100644
--- a/submissions/managers.py
+++ b/submissions/managers.py
@@ -82,6 +82,10 @@ class SubmissionManager(models.Manager):
         return self.exclude(status__in=SUBMISSION_EXCLUDE_FROM_REPORTING)
 
 
+class SubmissionEventQuerySet(models.QuerySet):
+    pass
+
+
 class EditorialAssignmentManager(models.Manager):
     def get_for_user_in_pool(self, user):
         return self.exclude(submission__authors=user.contributor)\