diff --git a/typings/vss.d.ts b/typings/vss.d.ts
index 7c1faf8..497cac7 100644
--- a/typings/vss.d.ts
+++ b/typings/vss.d.ts
@@ -3064,7 +3064,7 @@ interface WebPageGlobalizationContext {
 
 interface EventTarget {
     checked: boolean;
-    nodeType: number;
+    readonly nodeType: number;
 }
 
 interface Date {