UK != US jurisdiction (almost perhaps, but not quite)
Worried that the Chinese company would evade the US verdict by moving its assets outside US jurisdiction, Motorola filed in London for a freezing injunction against Hytera and two of its UK subsidiaries, Project Shortway Ltd and Sepura Ltd in April last year.
Whilst UK has a habit of cuddling up to the US, I still think its bit of a stretch to file in UK to enforce verdict in US.
Biting the hand that feeds IT
