diff --git a/phpBB/includes/db/migration/migration.php b/phpBB/includes/db/migration/migration.php
index 61fbf04320..4271751362 100644
--- a/phpBB/includes/db/migration/migration.php
+++ b/phpBB/includes/db/migration/migration.php
@@ -78,7 +78,7 @@ abstract class phpbb_db_migration
 	*
 	* @return array An array of migration class names
 	*/
-	public function depends_on()
+	static public function depends_on()
 	{
 		return array();
 	}