Call RemoveObjectToDestroy to remove an object instance from the list of temporary objects that TDataContext maintains. This prevents TDataContext from freeing the object when it is itself freed. 

For example, TRemotable descendants that are created by a Web Service application when it executes an invokable interface call are automatically added to a data context that persists for the length of the method call. When an application changes the remotable object's DataContext property, it automatically calls RemoveObjectToDestroy so that the object is not automatically freed when the method call is complete. 

DataContext 

AddObjectToDestroy