The World Trade Organization (WTO) Appellate Body issued a decision today rejecting claims by Panama that a set of defensive tax measures maintained by Argentina are inconsistent with the obligations of most-favored nation and national treatment under the General Agreement on Trade in Services (GATS).  The ruling effectively ensures that WTO members may continue to maintain laws and regulations that protect national tax revenues against the consequences of taxpayers engaging in transactions with non-transparent jurisdictions.  Steptoe represented the Government of Argentina in this dispute.