diff --git a/static/js/compose_fade.js b/static/js/compose_fade.js
index 5f1377b883..a9cc6912af 100644
--- a/static/js/compose_fade.js
+++ b/static/js/compose_fade.js
@@ -121,8 +121,7 @@ exports.would_receive_message = function (email) {
     }
 
     // PM, so check if the given email is in the recipients list.
-    var recipients = focused_recipient.reply_to.toLowerCase().split(',');
-    return recipients.indexOf(email.toLowerCase()) !== -1;
+    return util.is_pm_recipient(email, focused_recipient);
 };
 
 function _fade_users() {
diff --git a/static/js/util.js b/static/js/util.js
index 8b515dad1c..473aaf8fcb 100644
--- a/static/js/util.js
+++ b/static/js/util.js
@@ -65,6 +65,11 @@ exports.is_current_user = function (email) {
     return email.toLowerCase() === page_params.email.toLowerCase();
 };
 
+exports.is_pm_recipient = function (email, message) {
+    var recipients = message.reply_to.toLowerCase().split(',');
+    return recipients.indexOf(email.toLowerCase()) !== -1;
+};
+
 exports.same_major_recipient = function (a, b) {
     // Same behavior as same_recipient, except that it returns true for messages
     // on different topics but the same stream.