I just upgraded to DraftSight 2019 Standard after using DraftSight, free edition, for many years. Anytime I try and open these drawings with a viewer, other than DraftSight, i receive a message that it was Produced by an Autodesk Student version. It adds this to any printed copies as well. It doesn't do this with 2018, 2017, etc. Do I need to purchase the Professional Edition?