Mark Yopp wrote this bylined article analyzing state enactment of broader nexus laws (especially for sales and use taxes) to increase their revenues. As more states expand nexus, Mr. Yopp urged companies to “monitor legislative and litigation developments on nexus to prepare for what is coming” and to “be wary of any state that attempts to use nexus expansion to go after past tax liability, rather than collecting and remitting on a prospective basis.”