Arbitration analysis: This case dealt with an appeal filed by the Republic of India (‘India’) seeking to set aside an order permitting Deutsche Telekom AG (‘Deutsche Telekom’) to enforce a foreign arbitral award rendered against India. The appeal stemmed from proceedings before the Permanent Court of Arbitration (‘PCA’) governed by the United Nations Commission on International Trade Law (‘UNCITRAL’) Arbitration Rules, 1976 (‘UNCITRAL Rules’) and seated in Geneva, Switzerland, following Deutsche Telekom’s claim for the violation of the Agreement between the Federal Republic of Germany and the Republic of India for the Promotion and Protection of Investments (‘India-Germany BIT’). Following an arbitral award in Deutsche Telekom’s favour, the parties engaged in a series of proceedings for setting aside and subsequent enforcement proceedings. While dealing with India’s appeal, the Singapore Court of Appeal (‘SGCA’) examined the issue of transnational res judicata/issue estoppel to determine whether India would be precluded from re-litigating issues surrounding the validity of the arbitral award, which have previously been raised and have already been decided by the seat court. The decision delves into the question of how an enforcement court ought to treat earlier decisions rendered by the seat court and whether such enforcement court should grant primacy to the seat court’s decision. Answering in the affirmative and dismissing India’s appeal, SGCA held that the seat court’s decision would have a preclusive effect and transnational res judicata/issue estoppel would be applicable. While arriving at this conclusion, the SGCA noted that although the governing Convention on the Recognition and Enforcement of Foreign Arbitral Awards, 1958 (‘New York Convention’) did not expressly mention transnational res judicata/issue estoppel as a ground for refusing enforcement of an arbitral award, the principle could (and should) be invoked by an enforcement court in order to give effect to a prior decision rendered by the seat court (on the same issues). By settling the question of whether transnational res judicata//issue estoppel applies to international arbitration in Singapore, this decision serves to provide greater certainty to enforcement proceedings brought forth in Singapore under the aegis of the New York Convention and reduces avenues for parties to engage in refractory tactics to avoid the consequences of arbitral awards. Further, the court’s acknowledgement of the ‘primacy principle’ accords due regard to the decisions rendered by the seat court and serves to promote effectiveness as well as efficiency to the arbitration process as a whole, with-(a) parties having greater certainty on the applicability of their chosen governing systems of law; and (b) arbitration proceedings attaining finality expeditiously. Written by Ila Kapoor, partner at Shardul Amarchand Mangaldas & Co, New Delhi; Kshipra Pyare & Rachit Bansal, associates at Shardul Amarchand Mangaldas & Co, New Delhi.