diff --git a/pre-upload.py b/pre-upload.py
index b8ed460..789e53a 100755
--- a/pre-upload.py
+++ b/pre-upload.py
@@ -645,7 +645,7 @@
   if project.name not in ALLOWLIST:
     return None
 
-  TAGS = (
+  TAGS = {
       'Reviewed-on',
       'Reviewed-by',
       'Signed-off-by',
@@ -659,15 +659,14 @@
       'Suggested-by',
       'Reported-by',
       'Acked-for-chrome-by',
-  )
+  }
 
   # Ignore tags, which could reasonably contain OEM names
   # (e.g. Reviewed-by: foo@oem.corp-partner.google.com).
-  def tag_filter(x):
-    return not any(x.lower().startswith(h.lower()) for h in TAGS)
-
   commit_message = ' '.join(
-      filter(tag_filter, _get_commit_desc(commit).splitlines()))
+      x for x in _get_commit_desc(commit).splitlines()
+      if ':' not in x or x.split(':', 1)[0] not in TAGS)
+
   commit_message = re.sub(r'[\s_-]+', ' ', commit_message)
 
   # Exercise caution when expanding these lists. Adding a name
diff --git a/pre-upload_unittest.py b/pre-upload_unittest.py
index c553651..5fadf24 100755
--- a/pre-upload_unittest.py
+++ b/pre-upload_unittest.py
@@ -1279,6 +1279,9 @@
     self.assertMessageRejected(
         'Asus project\n'
         'Reviewed-by: partner@asus.corp-partner.google.com')
+    self.assertMessageRejected(
+        'my project\n'
+        'Bad-tag: partner@asus.corp-partner.google.com')
 
 
 class CheckCommitMessageStyle(CommitMessageTestCase):