diff --git a/Pilz.Net/Api/ApiMessage.cs b/Pilz.Net/Api/ApiMessage.cs
index b60cbc5..5f8059c 100644
--- a/Pilz.Net/Api/ApiMessage.cs
+++ b/Pilz.Net/Api/ApiMessage.cs
@@ -1,4 +1,6 @@
-namespace Pilz.Net.Api;
+using Newtonsoft.Json;
+
+namespace Pilz.Net.Api;
 
 public abstract class ApiMessage
 {
@@ -6,5 +8,6 @@ public abstract class ApiMessage
 
     public static ApiMessage Empty { get; } = new EmptyApiMessage();
 
+    [JsonIgnore]
     public bool IsEmpty => this is EmptyApiMessage;
 }