The English courts have a discretionary power to issue anti-suit injunctions restraining foreign court or arbitral proceedings, except in respect of cases before the courts of other EU or EFTA states (see Case 159/02, Turner v Grovit and Case C-185/07, Allianz SpA v West Tankers Inc).
The essential requirement for the exercise of that power is that the courts must have personal jurisdiction over the defendant. This means that there must be a basis upon which to serve a claim form on the defendant.
In cases that fall outside the Brussels and Lugano regimes, the courts will need to be satisfied that the criteria for service out of the jurisdiction are met, as set out above (see further CPR rr. 6.36-6.37 and PD 6B para, 3.1). One of the key criteria – and thus one of the key bases of challenge to jurisdiction by way of a CPR Part 11 application – is that England is the appropriate forum for the claim (i.e., it is not a forum non conveniens).
Once personal jurisdiction is established, the remaining basic conditions for the grant of an anti-suit injunction are that (i) the relevant English court is the appropriate forum for the resolution of the dispute and (ii) the foreign proceedings are vexatious or oppressive.
Once the applicant has established a prima facie case that the foreign proceedings are vexatious or oppressive, the respondent is entitled to show why an anti-suit injunction would nonetheless be unjust. This may be because, for example, there are substantive or procedural advantages available to him only in the foreign court.
While EU law prevents the issue of anti-suit injunctions to restrain proceedings in other EU or EFTA courts, the same does not apply to orders issued by arbitration tribunals (see Case C-536/13, Gazprom). This means that arbitrators can grant anti-suit injunctions affecting proceedings in member state courts, but the extent to which their awards are enforceable will depend on the laws of the country in question.