The Article 25 appeal arbitral award in the WTO dispute DS583: Turkey – Certain Measures concerning the Production, Importation and Marketing of Pharmaceutical Products has several distinctions. It emerges in the backdrop of the Covid-19 pandemic and at a time when the WTO continues to look for a solution to the ongoing Appellate Body impasse. On the substantive side, the dispute examines whether procurement by private entities towards public healthcare mandate could fall within the ‘government procurement’ derogation of the GATT 1994. In addition, the excessive focus on the ‘design test’ at the provisional stage in the invocation of general exceptions under GATT Article XX has key implications for future disputes. The dispute is also historic as it is the first time that parties to a WTO dispute took recourse to Article 25 of the WTO DSU, considered as an alternative form of dispute settlement, apparently to mimic the appellate review process which the Appellate Body used to perform. The article focuses on the substantive and procedural issues discussed in the dispute, and how the WTO Panel, and subsequently, an Article 25 arbitration addressed a number of such novel issues. In this exercise, the article also comments on the unique modus operandi of the Article 25 ad hoc arbitration mechanism.