I reviewed  EWCA Civ 1609 Koza v Akcil in my post here. The case concerns the application of Article 24(2) of the Brussels I Recast Regulation, which assigns exclusive jurisdiction to the Courts of the Member State of the seat in matters relating to the life and death of companies and of the validity of decisions made by their organs:
in proceedings which have as their object the validity of the constitution, the nullity or the dissolution of companies or other legal persons or associations of natural or legal persons, or of the validity of the decisions of their organs, the courts of the Member State in which the company, legal person or association has its seat. In order to determine that seat, the court shall apply its rules of private international law;
Referring particularly to C-144/10 BVG and to C-372/07 Hassett, the Court of Appeal found that the case as a whole fundamentally concerns one and the same issue of the validity of decisions of the organs of the company, Koza Ltd, an English subsidiary of a Turkish company.
Now the Supreme Court has disagreed. At 33, Lord Sales writes for the consensus opinion:
the Court of Appeal held that article 24(2) of the Recast Regulation required the court to “form an overall evaluative judgment as to what the proceedings are principally concerned with” (para 46). But this approach had the effect of expanding the application of article 24(2) (ex article 22(2) of Regulation No 44/2001), contrary to the guidance in the Hassett case and the BVG case, rather than narrowing its application, as the Court of Justice had been at pains to do in its judgments in those cases.
it is the guidance in paras 22-25 of the Hassett judgment which is relevant, to the effect that a mere link between a claim which engages article 24(2) and one which does not is not sufficient to bring the latter within the scope of that provision
Further authority was sought in particular from Schmidt v Schmidt (C-417/15) which I reviewed here, and EON Czech Holding AG v Dědouch (C-560/16), my review here. Acte clair – no reference to the CJEU required. Conclusion, at 43: ‘the English courts cannot assert jurisdiction over Koza Altin [Turkey] and the trustees in relation to that claim in the present proceedings on the basis of [A24(2)], and their appeal in that regard should be allowed.’ However: at 44: given that Turkey is not an EU Member State, the English courts may be able to assert jurisdiction over them by means of a provision in residual English PIL.
(Handbook of) EU Private International Law, 2nd ed. 2016, Chapter 2, Heading 2.2.6, Heading 18.104.22.168.