diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Report/ModuleInventory.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Report/ModuleInventory.pm
index e37c2a6a..c31ee518 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Report/ModuleInventory.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Report/ModuleInventory.pm
@@ -88,7 +88,7 @@ get '/ajax/content/report/moduleinventory' => require_login sub {
    }
     else {
         @results = $rs->search(
-            {},
+            {class => { '!=', undef }},
             {   select   => [ 'class', { count => 'class' } ],
                 as       => [qw/ class count /],
                 group_by => [qw/ class /]
diff --git a/Netdisco/share/views/ajax/report/moduleinventory.tt b/Netdisco/share/views/ajax/report/moduleinventory.tt
index 333b0044..a5453ff3 100644
--- a/Netdisco/share/views/ajax/report/moduleinventory.tt
+++ b/Netdisco/share/views/ajax/report/moduleinventory.tt
@@ -65,7 +65,7 @@ $(document).ready(function() {
       }, {
         "data": 'class',
         "render": function(data, type, row, meta) {
-          return '<a href="[% uri_for('/report/moduleinventory') %]?class=' + encodeURIComponent(data) + '">' + he.encode(capitalizeFirstLetter(data)) + '</a>';
+          return '<a href="[% uri_for('/report/moduleinventory') %]?class=' + encodeURIComponent(data) + '">' + he.encode(capitalizeFirstLetter(data + '')) + '</a>';
         }
       }, {
         "data": 'type',
@@ -101,7 +101,7 @@ $(document).ready(function() {
       [% ELSE %] {
         "data": 'class',
         "render": function(data, type, row, meta) {
-          return '<a href="[% uri_for('/report/moduleinventory') %]?class=' + encodeURIComponent(data) + '">' + he.encode(capitalizeFirstLetter(data)) + '</a>';
+          return '<a href="[% uri_for('/report/moduleinventory') %]?class=' + encodeURIComponent(data) + '">' + he.encode(capitalizeFirstLetter(data + '')) + '</a>';
         }
       }, {
         "data": 'count',