  Typed feature structures are used extensively for the specification of
linguistic information in many formalisms. The subsumption relation orders TFSs
by their information content. We prove that subsumption of acyclic TFSs is
well-founded, whereas in the presence of cycles general TFS subsumption is not
well-founded. We show an application of this result for parsing, where the
well-foundedness of subsumption is used to guarantee termination for grammars
that are off-line parsable. We define a new version of off-line parsability
that is less strict than the existing one; thus termination is guaranteed for
parsing with a larger set of grammars.
