diff --git a/actions/apitimelinegroup.php b/actions/apitimelinegroup.php
index a85da4b0f3..e1bc102e45 100644
--- a/actions/apitimelinegroup.php
+++ b/actions/apitimelinegroup.php
@@ -125,10 +125,6 @@ class ApiTimelineGroupAction extends ApiPrivateAuthAction
             header('Content-Type: application/atom+xml; charset=utf-8');
 
             try {
-                $atom->addAuthorRaw($this->group->asAtomAuthor());
-                $atom->setActivitySubject($this->group->asActivitySubject());
-                $atom->setId($self);
-                $atom->setSelfLink($self);
                 $atom->addEntryFromNotices($this->notices);
                 $this->raw($atom->getString());
             } catch (Atom10FeedException $e) {
diff --git a/lib/atom10feed.php b/lib/atom10feed.php
index 3ae9dc81be..881df6605f 100644
--- a/lib/atom10feed.php
+++ b/lib/atom10feed.php
@@ -146,15 +146,16 @@ class Atom10Feed extends XMLStringer
     }
 
     /**
-     * Add a activity feed subject via raw XML string
+     * Deprecated <activity:subject>; ignored
      *
      * @param string $xmlSubject An XML string representation of the subject
      *
      * @return void
      */
+
     function setActivitySubject($xmlSubject)
     {
-        $this->subject = $xmlSubject;
+        throw new ServerException(_('Don\'t use this method!'));
     }
 
     function getNamespaces()
diff --git a/lib/atomgroupnoticefeed.php b/lib/atomgroupnoticefeed.php
index 39a1fd456e..5b6fcf4295 100644
--- a/lib/atomgroupnoticefeed.php
+++ b/lib/atomgroupnoticefeed.php
@@ -85,8 +85,9 @@ class AtomGroupNoticeFeed extends AtomNoticeFeed
         $this->setId($self);
         $this->setSelfLink($self);
 
-        $this->addAuthorRaw($group->asAtomAuthor());
-        $this->setActivitySubject($group->asActivitySubject());
+        $ao = ActivityObject::fromGroup($group);
+
+        $this->addAuthorRaw($ao->asString('author'));
 
         $this->addLink($group->homeUrl());
     }
diff --git a/lib/atomusernoticefeed.php b/lib/atomusernoticefeed.php
index ec368f5ca1..5ca089b859 100644
--- a/lib/atomusernoticefeed.php
+++ b/lib/atomusernoticefeed.php
@@ -60,8 +60,8 @@ class AtomUserNoticeFeed extends AtomNoticeFeed
         $this->user = $user;
         if (!empty($user)) {
             $profile = $user->getProfile();
-            $this->addAuthor($profile->nickname, $user->uri);
-            $this->setActivitySubject($profile->asActivityNoun('subject'));
+            $ao = ActivityObject::fromProfile($profile);
+            $this->addAuthorRaw($ao->asString('author'));
         }
 
         // TRANS: Title in atom user notice feed. %s is a user name.
diff --git a/plugins/OStatus/OStatusPlugin.php b/plugins/OStatus/OStatusPlugin.php
index d0b64e8769..86bd15e0b7 100644
--- a/plugins/OStatus/OStatusPlugin.php
+++ b/plugins/OStatus/OStatusPlugin.php
@@ -145,12 +145,10 @@ class OStatusPlugin extends Plugin
             $user = $feed->getUser();
             $id   = $user->id;
             $profile = $user->getProfile();
-            $feed->setActivitySubject($profile->asActivityNoun('subject'));
         } else if ($feed instanceof AtomGroupNoticeFeed) {
             $salmonAction = 'groupsalmon';
             $group = $feed->getGroup();
             $id = $group->id;
-            $feed->setActivitySubject($group->asActivitySubject());
         } else {
             return true;
         }