diff --git a/application/library/View/Helper/BulletinEntryDiff.php b/application/library/View/Helper/BulletinEntryDiff.php
index 2feda079c3795690692afe8507885030fa09ceba..8b600b663e381508ef00ed1b1a4bf9733ac8eedd 100644
--- a/application/library/View/Helper/BulletinEntryDiff.php
+++ b/application/library/View/Helper/BulletinEntryDiff.php
@@ -30,7 +30,7 @@ class Application_View_Helper_BulletinEntryDiff
                 if($crosslisting->type == 'home listing') {
                     continue;
                 }
-                if($crosslisting->subject == $course->subject) {
+                if($crosslisting->subject == $currentCourse->subject) {
                     $currentCourseId .= '/' . $crosslisting->courseNumber . $crosslisting->courseLetter;
                 }
             }
@@ -44,7 +44,7 @@ class Application_View_Helper_BulletinEntryDiff
                 if($crosslisting->type == 'home listing') {
                     continue;
                 }
-                if($crosslisting->subject == $course->subject) {
+                if($crosslisting->subject == $proposedCourse->subject) {
                     $proposedCourseId .= '/' . $crosslisting->courseNumber . $crosslisting->courseLetter;
                 }
             }
@@ -59,7 +59,7 @@ class Application_View_Helper_BulletinEntryDiff
                 if ($crosslisting->type == 'home listing') {
                     continue;
                 }
-                if($crosslisting->subject == $course->subject) {
+                if($crosslisting->subject == $currentCourse->subject) {
                     $currentCorrespondence .= '/' . $crosslisting->courseNumber . $crosslisting->courseLetter . 'x';
                 }
             }
@@ -71,7 +71,7 @@ class Application_View_Helper_BulletinEntryDiff
                 if ($crosslisting->type == 'home listing') {
                     continue;
                 }
-                if($crosslisting->subject == $course->subject) {
+                if($crosslisting->subject == $proposedCourse->subject) {
                     $proposedCorrespondence .= '/' . $crosslisting->courseNumber . $crosslisting->courseLetter . 'x';
                 }
             }