diff --git a/auth/common.hh b/auth/common.hh
index 976085c690..071112cc08 100644
--- a/auth/common.hh
+++ b/auth/common.hh
@@ -30,8 +30,6 @@ namespace replica {
 class database;
 }
 
-class timeout_config;
-
 namespace service {
 class migration_manager;
 }