diff --git a/lib/Alchemy/Phrasea/Collection/Reference/ArrayCacheCollectionReferenceRepository.php b/lib/Alchemy/Phrasea/Collection/Reference/ArrayCacheCollectionReferenceRepository.php
index 7351351e93..64c80ae955 100644
--- a/lib/Alchemy/Phrasea/Collection/Reference/ArrayCacheCollectionReferenceRepository.php
+++ b/lib/Alchemy/Phrasea/Collection/Reference/ArrayCacheCollectionReferenceRepository.php
@@ -72,6 +72,25 @@ class ArrayCacheCollectionReferenceRepository implements CollectionReferenceRepo
         return null;
     }
 
+    /**
+     * @param array $baseIds
+     * @return CollectionReference[]
+     */
+    public function findMany(array $baseIds)
+    {
+        $references = $this->findAll();
+
+        $requested = [];
+
+        foreach ($baseIds as $baseId) {
+            if (isset($references[$baseId])) {
+                $requested[] = $references[$baseId];
+            }
+        }
+
+        return $requested;
+    }
+
     /**
      * @param int $databoxId
      * @param int $collectionId
@@ -90,6 +109,10 @@ class ArrayCacheCollectionReferenceRepository implements CollectionReferenceRepo
         return null;
     }
 
+    /**
+     * @param array|null $baseIdsSubset
+     * @return CollectionReference[]
+     */
     public function findHavingOrderMaster(array $baseIdsSubset = null)
     {
         return $this->repository->findHavingOrderMaster($baseIdsSubset);
diff --git a/lib/Alchemy/Phrasea/Collection/Reference/CollectionReferenceRepository.php b/lib/Alchemy/Phrasea/Collection/Reference/CollectionReferenceRepository.php
index fdbf7289d1..7740f8ddc9 100644
--- a/lib/Alchemy/Phrasea/Collection/Reference/CollectionReferenceRepository.php
+++ b/lib/Alchemy/Phrasea/Collection/Reference/CollectionReferenceRepository.php
@@ -29,6 +29,12 @@ interface CollectionReferenceRepository
      */
     public function find($baseId);
 
+    /**
+     * @param int[] $baseIds
+     * @return CollectionReference[]
+     */
+    public function findMany(array $baseIds);
+
     /**
      * @param int $databoxId
      * @param int $collectionId
diff --git a/lib/Alchemy/Phrasea/Collection/Reference/DbalCollectionReferenceRepository.php b/lib/Alchemy/Phrasea/Collection/Reference/DbalCollectionReferenceRepository.php
index a67f8cad3d..00c8101259 100644
--- a/lib/Alchemy/Phrasea/Collection/Reference/DbalCollectionReferenceRepository.php
+++ b/lib/Alchemy/Phrasea/Collection/Reference/DbalCollectionReferenceRepository.php
@@ -95,6 +95,25 @@ WHERE base_id = :baseId';
         return null;
     }
 
+    /**
+     * @param array $basesId
+     * @return CollectionReference[]
+     */
+    public function findMany(array $basesId)
+    {
+        if (empty($basesId)) {
+            return [];
+        }
+
+        $rows = $this->connection->fetchAll(
+            self::$selectQuery . ' WHERE base_id IN (:baseIds)',
+            ['baseIds' => $basesId],
+            ['baseIds' => Connection::PARAM_INT_ARRAY]
+        );
+
+        return $this->createManyReferences($rows);
+    }
+
     /**
      * @param int $databoxId
      * @param int $collectionId
diff --git a/lib/classes/ACL.php b/lib/classes/ACL.php
index b28c134af6..7bb0766e61 100644
--- a/lib/classes/ACL.php
+++ b/lib/classes/ACL.php
@@ -1763,20 +1763,39 @@ class ACL implements cache_cacheableInterface
     /**
      * Returns an array of collections on which the user is 'order master'
      *
-     * @return array
+     * @return collection[]
      */
     public function get_order_master_collections()
     {
         $sql = 'SELECT base_id FROM basusr WHERE order_master="1" AND usr_id= :usr_id';
-        $stmt = $this->app->getApplicationBox()->get_connection()->prepare($sql);
-        $stmt->execute([':usr_id' => $this->user->getId()]);
-        $rs = $stmt->fetchAll(\PDO::FETCH_ASSOC);
-        $stmt->closeCursor();
+        $result = $this->app->getApplicationBox()
+            ->get_connection()
+            ->executeQuery($sql, [':usr_id' => $this->user->getId()])
+            ->fetchAll(\PDO::FETCH_ASSOC);
+
+
+        $baseIds = [];
+
+        foreach ($result as $item) {
+            $baseIds[] = $item['base_id'];
+        }
+
+        $groups = [];
+
+        foreach ($this->app['repo.collection-references']->findHavingOrderMaster($baseIds) as $index => $reference) {
+            $databoxId = $reference->getDataboxId();
+            $group = isset($groups[$databoxId]) ? $groups[$databoxId] : [];
+
+            $group[$reference->getCollectionId()] = $index;
+            $groups[$databoxId] = $group;
+        }
 
         $collections = [];
 
-        foreach ($rs as $row) {
-            $collections[] = \collection::getByBaseId($this->app, $row['base_id']);
+        foreach ($groups as $databoxId => $group) {
+            foreach ($group as $collectionId => $index) {
+                $collections[$index] = \collection::getByCollectionId($this->app, $databoxId, $collectionId);
+            }
         }
 
         return $collections;
diff --git a/lib/classes/collection.php b/lib/classes/collection.php
index 7ac76177bb..9c56620c05 100644
--- a/lib/classes/collection.php
+++ b/lib/classes/collection.php
@@ -192,16 +192,17 @@ class collection implements ThumbnailedElement, cache_cacheableInterface
     }
 
     /**
-     * @param  Application $app
-     * @param  databox $databox
-     * @param  int $collectionId
+     * @param Application $app
+     * @param databox|int $databox
+     * @param int $collectionId
      * @return collection
      */
-    public static function getByCollectionId(Application $app, databox $databox, $collectionId)
+    public static function getByCollectionId(Application $app, $databox, $collectionId)
     {
         assert(is_int($collectionId));
+        $databoxId = $databox instanceof databox ? $databox->get_sbas_id() : (int)$databox;
 
-        return self::getAvailableCollection($app, $databox->get_sbas_id(), $collectionId);
+        return self::getAvailableCollection($app, $databoxId, $collectionId);
     }
 
     /**