diff --git a/spec.html b/spec.html
index 191761b..2bc01e1 100644
--- a/spec.html
+++ b/spec.html
@@ -403,7 +403,7 @@ <h1>DefineField(_receiver_, _fieldRecord_)</h1>
     1. Else,
       1. NOTE: _fieldName_ is a property key.
       1. Let _desc_ be PropertyDescriptor{
-           [[Configurable]]: *false*,
+           [[Configurable]]: *true*,
            [[Enumerable]]: *true*,
            [[Writable]]: *true*,
            [[Value]]: _initValue_