Guest post by Professor Yeo Tiong Min, SC (honoris causa), Yong Pung How Chair Professor of Law, Yong Pung How School of Law, Singapore Management University
Merck Sharp & Dohme Corp (formerly known as Merck & Co, Inc) v Merck KGaA (formerly known as E Merck)  1 SLR 1102,  SGCA 14 (“Merck”), noted previously, is a landmark case in Singapore private international law, being a decision of a full bench of the Court of Appeal setting out for the first time in Singapore law the limits of transnational issue estoppel. It was also the beginning of the deconstruction of the common law on the legal effect to be given to foreign judgments. Without ruling on the issue, the court was not convinced by the obligation theory as the rationale for the recognition of foreign in personam judgments under the common law, preferring instead to rest the law on the rationales of transnational comity and reciprocal respect among courts of independent jurisdictions. There was no occasion to depart from the traditional rules of recognition of in personam judgments in that case, and the court did not do so. However, the shift in the rationale suggested that changes could be forthcoming. While this sort of underlying movements have generally led to more expansive recognition of foreign judgments (eg, in Canada’s recognition of foreign judgments from courts with real and substantial connection to the underlying dispute), the indications in the case appeared to signal a restrictive direction, with the contemplation of a possible reciprocity requirement as a necessary condition for recognition of a foreign judgment, and a possible defence where the foreign court had made an error of Singapore domestic law.