diff --git a/src/applications/project/query/PhabricatorProjectQuery.php b/src/applications/project/query/PhabricatorProjectQuery.php
--- a/src/applications/project/query/PhabricatorProjectQuery.php
+++ b/src/applications/project/query/PhabricatorProjectQuery.php
@@ -260,14 +260,14 @@
 
     $all_graph = $this->getAllReachableAncestors($projects);
 
-    if ($this->needAncestorMembers || $this->needWatchers) {
-      $src_projects = $all_graph;
-    } else {
-      $src_projects = $projects;
-    }
+    // NOTE: Although we may not need much information about ancestors, we
+    // always need to test if the viewer is a member, because we will return
+    // ancestor projects to the policy filter via ExtendedPolicy calls. If
+    // we skip populating membership data on a parent, the policy framework
+    // will think the user is not a member of the parent project.
 
     $all_sources = array();
-    foreach ($src_projects as $project) {
+    foreach ($all_graph as $project) {
       // For milestones, we need parent members.
       if ($project->isMilestone()) {
         $parent_phid = $project->getParentProjectPHID();
@@ -306,7 +306,7 @@
     }
 
     $membership_projects = array();
-    foreach ($src_projects as $project) {
+    foreach ($all_graph as $project) {
       $project_phid = $project->getPHID();
 
       if ($project->isMilestone()) {