diff --git a/mocha-dotnet/src/lib/Mocha.Core/Modeling/OmsInstanceList.cs b/mocha-dotnet/src/lib/Mocha.Core/Modeling/OmsInstanceList.cs
index 6495436..08c4381 100644
--- a/mocha-dotnet/src/lib/Mocha.Core/Modeling/OmsInstanceList.cs
+++ b/mocha-dotnet/src/lib/Mocha.Core/Modeling/OmsInstanceList.cs
@@ -87,6 +87,7 @@ public class OmsInstanceList<T> : OmsInstanceList, IList<T> where T : OmsClass
 		{
 			Guid localClassGuid = OmsDatabase.GetGlobalIdentifierForClass(item.GetType());
 			Guid localInstanceGuid = Guid.NewGuid();
+			item.GlobalIdentifier = localInstanceGuid;
 
 			omsdb.CreateClass(item, localClassGuid, localInstanceGuid);
 		}