If the parties . . . have agreed that a court or the courts of a part of the United Kingdom are to have jurisdiction to settle any disputes which have arisen or which may arise in connection with a particular legal relationship, and, apart from this Schedule, the agreement would be effective to confer jurisdiction under the law of that part, that court or those courts shall have . . . jurisdiction . . .

The court or courts of a part of the United Kingdom on which a trust instrument has conferred jurisdiction shall have . . . jurisdiction in any proceedings brought against a settlor, trustee or beneficiary, if relations between these persons or their rights or obligations under the trust are involved.

Agreements or provisions of a trust instrument conferring jurisdiction shall have no legal force if they are contrary to the provisions of Article ... 15, or if the courts whose jurisdiction they purport to exclude have exclusive jurisdiction by virtue of Article 16.

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