diff --git a/src/applications/phame/editor/PhamePostEditor.php b/src/applications/phame/editor/PhamePostEditor.php
index e3cd1a4417..c816ecfed6 100644
--- a/src/applications/phame/editor/PhamePostEditor.php
+++ b/src/applications/phame/editor/PhamePostEditor.php
@@ -237,6 +237,8 @@ final class PhamePostEditor
     return array(
       PhamePostTransaction::MAILTAG_CONTENT =>
         pht("A post's content changes."),
+      PhamePostTransaction::MAILTAG_SUBSCRIBERS =>
+        pht("A post's subscribers change."),
       PhamePostTransaction::MAILTAG_COMMENT =>
         pht('Someone comments on a post.'),
       PhamePostTransaction::MAILTAG_OTHER =>
diff --git a/src/applications/phame/storage/PhamePostTransaction.php b/src/applications/phame/storage/PhamePostTransaction.php
index 5e28b87198..063bc4ad66 100644
--- a/src/applications/phame/storage/PhamePostTransaction.php
+++ b/src/applications/phame/storage/PhamePostTransaction.php
@@ -9,6 +9,7 @@ final class PhamePostTransaction
   const TYPE_VISIBILITY       = 'phame.post.visibility';
 
   const MAILTAG_CONTENT       = 'phame-post-content';
+  const MAILTAG_SUBSCRIBERS   = 'phame-post-subscribers';
   const MAILTAG_COMMENT       = 'phame-post-comment';
   const MAILTAG_OTHER         = 'phame-post-other';
 
@@ -72,6 +73,9 @@ final class PhamePostTransaction
       case PhabricatorTransactions::TYPE_COMMENT:
         $tags[] = self::MAILTAG_COMMENT;
         break;
+      case PhabricatorTransactions::TYPE_SUBSCRIBERS:
+        $tags[] = self::MAILTAG_SUBSCRIBERS;
+        break;
       case self::TYPE_TITLE:
       case self::TYPE_PHAME_TITLE:
       case self::TYPE_BODY: