diff --git a/Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Runtime/HideInTypeMenuAttribute.cs b/Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Runtime/HideInTypeMenuAttribute.cs
new file mode 100644
index 0000000..716aaac
--- /dev/null
+++ b/Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Runtime/HideInTypeMenuAttribute.cs
@@ -0,0 +1,11 @@
+#if UNITY_2019_3_OR_NEWER
+using System;
+
+/// <summary>
+/// An attribute that hides the type in the SubclassSelector.
+/// </summary>
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct | AttributeTargets.Enum | AttributeTargets.Interface, AllowMultiple = false, Inherited = false)]
+public sealed class HideInTypeMenuAttribute : Attribute {
+
+}
+#endif
\ No newline at end of file
diff --git a/Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Runtime/HideInTypeMenuAttribute.cs.meta b/Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Runtime/HideInTypeMenuAttribute.cs.meta
new file mode 100644
index 0000000..dd44d0d
--- /dev/null
+++ b/Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Runtime/HideInTypeMenuAttribute.cs.meta
@@ -0,0 +1,11 @@
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