diff --git a/sharethis.module b/sharethis.module
index cf8f0b3..9e6fa5f 100644
--- a/sharethis.module
+++ b/sharethis.module
@@ -83,7 +83,7 @@ function sharethis_node_view($node, $view_mode, $langcode) {
 
   // Check where we want to display the ShareThis widget.
   $location = variable_get('sharethis_location', array('content'));
-  if (in_array('content', $location)) {
+  if (in_array('content', $location, TRUE)) {
     $enabled_types = $data_options['sharethis_node_types'];
     if (isset($enabled_types[$node->type]) && $enabled_types[$node->type] === $node->type) {
       $display_settings = field_extra_fields_get_display('node', $node->type, $view_mode);
@@ -106,7 +106,7 @@ function sharethis_node_view($node, $view_mode, $langcode) {
     }
   }
 
-  if (in_array('links', $location)) {
+  if (in_array('links', $location, TRUE)) {
     $enabled_view_modes = variable_get('sharethis_' . $node->type . '_options', array());
     if (isset($enabled_view_modes[$view_mode]) && $enabled_view_modes[$view_mode]) {
       $links['sharethis'] = array(
@@ -145,7 +145,7 @@ function sharethis_field_extra_fields() {
   $extra = array();
   // Only add extra fields if the location is the node content.
   $location = variable_get('sharethis_location', array('content'));
-  if (in_array('content', $location)) {
+  if (in_array('content', $location, TRUE)) {
     $entity_info = entity_get_info('node');
     foreach ($entity_info['bundles'] as $bundle => $bundle_info) {
       $extra['node'][$bundle]['display'] = array(
@@ -452,7 +452,7 @@ function sharethis_block_view($delta = '') {
  */
 function sharethis_block_contents() {
   $location = variable_get('sharethis_location', array('content'));
-  if (in_array('block', $location)) {
+  if (in_array('block', $location, TRUE)) {
     // Output the embedded JavaScript.
     sharethis_include_js();
     $cache_name = 'sharethis:sharethis_block:' . current_path();