Adding options to View filter settings
1) Add new custom views filter handler that extends views_handler_filter_in_operator

class MY_MODULE_own_company_filter_handler extends views_handler_filter_in_operator {

  public function get_value_options() {
    $options = parent::get_value_options();
    $options['own'] = 'Own Company';
    $this-&gt;value_options = $options;

    return $this-&gt;value_options;
  }

  /**
   * Replaces "Own Company" value with real value. 
   * Do query alter here or in query() function.
   */
  function pre_query() {
    parent::pre_query();

    // Check if "Own Company" was chosen.
    if (!empty($this-&gt;value['own'])) {

      // Unset "Own Company" 'own' value.
      unset($this-&gt;value['own']);

      // Get current "Own Company" value the way you like.
      $company_id = 100500; // Example value.

      // Set current "Own Company" value.
      $this-&gt;value[$company_id] = $company_id;
    }
  }

}


2) Implement hook_views_data_alter() and add custom handler to all entityreference field filters

/**
 * Implements hook_views_data_alter().
 */
function MY_MODULE_views_data_alter(&amp;$data) {
  // Loop all field filters.
  foreach ($data as $data_key =&gt; $data_field) {
    if (strpos($data_key, 'field_data_') !== FALSE) {

      // Get field name
      $field_name = str_replace('field_data_', '', $data_key);

      // Check if field filter is entity reference 
      if (isset($data_field[$field_name . '_target_id']['filter']['handler'])) {
        if ($data_field[$field_name . '_target_id']['filter']['handler'] == 'views_handler_filter_in_operator') {

          // Name of custom handler class
          $custom = 'MY_MODULE_own_company_filter_handler';
          // Add custom handler
          $data[$data_key][$field_name . '_target_id']['filter']['handler'] = $custom;

        }
      }
    }
  }
}