diff --git a/src/controllers/WorkflowController.ts b/src/controllers/WorkflowController.ts
index 502f96bb..ec31c40d 100644
--- a/src/controllers/WorkflowController.ts
+++ b/src/controllers/WorkflowController.ts
@@ -299,6 +299,7 @@ export class WorkflowController extends Controller {
         can_change_state: false,
         can_delete: false,
         can_cancel: false,
+        can_sign: false,
       });
     }
     return new HttpSuccess({
@@ -312,6 +313,7 @@ export class WorkflowController extends Controller {
       can_change_state: operator.canChangeState,
       can_delete: operator.canDelete,
       can_cancel: operator.canCancel,
+      can_sign: operator.canSign,
     });
   }