diff --git a/types/kendo-ui/index.d.ts b/types/kendo-ui/index.d.ts
index 327a2c6077..4ecb8e0ab0 100644
--- a/types/kendo-ui/index.d.ts
+++ b/types/kendo-ui/index.d.ts
@@ -997,6 +997,7 @@ declare namespace kendo.data {
         max?: any;
         minLength?: any;
         maxLength?: any;
+        [rule: string]: any;
     }
 
     class ObservableArray extends Observable {