diff --git a/src/applications/maniphest/query/ManiphestTaskQuery.php b/src/applications/maniphest/query/ManiphestTaskQuery.php
--- a/src/applications/maniphest/query/ManiphestTaskQuery.php
+++ b/src/applications/maniphest/query/ManiphestTaskQuery.php
@@ -304,6 +304,12 @@
       $projects = mpull($projects, null, 'getPHID');
 
       foreach ($tasks as $key => $task) {
+        if (!$task->getGroupByProjectPHID()) {
+          // This task is either not in any projects, or only in projects
+          // which we're ignoring because they're being queried for explicitly.
+          continue;
+        }
+
         if (empty($projects[$task->getGroupByProjectPHID()])) {
           unset($tasks[$key]);
         }
diff --git a/src/applications/maniphest/view/ManiphestTaskResultListView.php b/src/applications/maniphest/view/ManiphestTaskResultListView.php
--- a/src/applications/maniphest/view/ManiphestTaskResultListView.php
+++ b/src/applications/maniphest/view/ManiphestTaskResultListView.php
@@ -170,7 +170,12 @@
         if ($label_key) {
           return $handles[$label_key]->getFullName();
         } else {
-          return pht('(No Project)');
+          // This may mean "No Projects", or it may mean the query has project
+          // constraints but the task is only in constrained projects (in this
+          // case, we don't show the group because it would always have all
+          // of the tasks). Since distinguishing between these two cases is
+          // messy and the UI is reasonably clear, label generically.
+          return pht('(Ungrouped)');
         }
       default:
         return pht('Tasks');