@@ -553,6 +553,7 @@ md5 of the content::
 {
 $response = $this->render('MyBundle:Main:index.html.twig');
 $response->setETag(md5($response->getContent()));
+$response->setPublic(); // make sure the response is public/cacheable
 $response->isNotModified($this->getRequest());
 
 return $response;
@@ -604,7 +605,14 @@ header value::
 $date = $authorDate > $articleDate ? $authorDate : $articleDate;
 
 $response->setLastModified($date);
-$response->isNotModified($this->getRequest());
+// Set response as public. Otherwise it will be private by default.
+$response->setPublic();
+
+if ($response->isNotModified($this->getRequest())) {
+return $response;
+}
+
+// do more work to populate the response will the full content
 
 return $response;
 }
@@ -846,6 +854,7 @@ independent of the rest of the page.
 public function indexAction()
 {
 $response = $this->render('MyBundle:MyController:index.html.twig');
+// set the shared max age - the also marks the response as public
 $response->setSharedMaxAge(600);
 
 return $response;