The subclassSharedTransientAllowed class option enables you to set the sharedTransientAllowed and subclassSharedTransientAllowed class option values for all subclasses of this class.
When the subclassSharedTransientAllowed option is set to false on a superclass by unchecking the Allow Shared Transient Subclass Instances check box on the Lifetime sheet of the Define Class dialog, the Allow Shared Transient Instances and Allow Shared Transient Subclass Instances check boxes are disabled on the Lifetime sheet of the Define Class dialog for all subclasses of the current class so that you cannot change these values. (For details, see "Adding Classes to Your Schema", in Chapter 3.)