The US corporate tax regime can put US-based multinationals at a competitive disadvantage, leading them to migrate. US anti-inversion rules have ceased to halt the trend. Changes made a year ago point towards migration through mergers with sizeable non-US corporations, which can reduce the impact of the anti-inversion rules. Such mergers are likely to involve a US forward or reverse triangular merger coupled, in the case of the UK, with a court scheme of arrangement which can reduce the tax costs of the combination to an acceptable level.