2 different stories there, yellow bought Preston which owned Saia and West ex . They spun Preston off on their own and eventually they went Under. Yellow then bought Jevic, suppose to have a full non union cross country LTL. The merged Westex and Saia then ended up spinning them off and selling Jevic to Jeffries and that led to their demise. Saia has been the only company that Yellow bought and spun off that has survived.