diff --git a/files/helpers/actions.py b/files/helpers/actions.py
index 0cd7f10e1..b159b5449 100644
--- a/files/helpers/actions.py
+++ b/files/helpers/actions.py
@@ -3,7 +3,9 @@ from files.classes.badges import Badge
 from files.helpers.alerts import send_repeatable_notification
 
 def badge_grant(user, badge_id, description=None, url=None):
-	if not user or user.has_badge(badge_id):
+	if not user:
+		raise ValueError('badge_grant: expected user, not None')
+	if user.has_badge(badge_id):
 		return
 
 	badge = Badge(
diff --git a/files/routes/comments.py b/files/routes/comments.py
index 3d6d05493..82ab29cb5 100644
--- a/files/routes/comments.py
+++ b/files/routes/comments.py
@@ -279,7 +279,8 @@ def api_comment(v):
 
 							all_by_author = g.db.query(Marsey).filter_by(author_id=user.id).count()
 
-							if all_by_author >= 10:
+							# off-by-one: newly added marsey isn't counted
+							if all_by_author >= 9:
 								badge_grant(badge_id=16, user=user)
 							else:
 								badge_grant(badge_id=17, user=user)
diff --git a/files/routes/login.py b/files/routes/login.py
index 03c12c2a9..e69c63cbd 100644
--- a/files/routes/login.py
+++ b/files/routes/login.py
@@ -338,9 +338,10 @@ def sign_up_post(v):
 
 		if ref_user:
 			badge_grant(user=ref_user, badge_id=10)
-			if ref_user.referral_count >= 10:
+			# off-by-one: newly referred user isn't counted
+			if ref_user.referral_count >= 9:
 				badge_grant(user=ref_user, badge_id=11)
-			if ref_user.referral_count >= 100:
+			if ref_user.referral_count >= 99:
 				badge_grant(user=ref_user, badge_id=12)
 
 	if email: