diff --git a/Lib9c.MessagePack/Action/NCActionEvaluation.cs b/Lib9c.MessagePack/Action/NCActionEvaluation.cs
index 35f2b94a68..f977a3489d 100644
--- a/Lib9c.MessagePack/Action/NCActionEvaluation.cs
+++ b/Lib9c.MessagePack/Action/NCActionEvaluation.cs
@@ -49,7 +49,9 @@ public struct NCActionEvaluation
 
         [Key(8)]
         [MessagePackFormatter(typeof(TxIdFormatter))]
+ #pragma warning disable MsgPack003
         public TxId? TxId { get; set; }
+ #pragma warning restore MsgPack003
 
         [SerializationConstructor]
         public NCActionEvaluation(