In P & O Nedlloyd BV v Arab Metals Co & Anor [2006] EWCA Civ 1717 [2007] 1 WLR 2288 the Court of Appeal held that where an appeal set aside an order below the judgment appealed from was a nullity and the findings on which it was based could not found an estoppel as between the parties. Thus said More-Bick LJ:
29 ... Issue estoppel is a form of estoppel by record and depends ... on a decision of the court disposing of a substantive dispute between the parties. On a purely formal level it may be said that the setting aside of the order below expunges the only record from which an estoppel was capable of deriving its force. At a substantive level the setting aside of the order means that there is no longer any disposal to which the decision on the issue in question...
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