List groups own content and all non-group content on groups page
Solved! I used hook_views_query_alter().

function MY_MODULE_views_query_alter(&amp;$view, &amp;$query) {
  if($view-&gt;name == 'VIEW_NAME') {
    foreach ($query-&gt;where as &amp;$condition_group) {
      foreach ($condition_group['conditions'] as &amp;$condition) {
        if (strpos($condition['field'], 'og_membership_node.gid') === 0) {
          $condition_group['conditions'][] = array(
            'field' =&gt; 'og_membership_node.gid',
            'value' =&gt; NULL,
            'operator' =&gt; 'is'
          );
          $condition_group['type'] = 'OR';
        }
      }
    }
  }
}