The announced changes to the US inversion rules will not turn one of the insurance industry's most high-profile mergers on its head, the firm involved announced late last week.
Willis Towers Watson, which was formed out of the successful merger of Towers Watson and Willis Group Holdings in January, issued a statement remarking that it did not believe the rule change would cause its merger to be treated as an inversion.
As a result, Willis Towers Watson also does not believe that the rule change will have an effect on any of its intercompany debt, including debt which had been created because of the merger, and it still predicts the joining of the two firms will create at least $75m (£53.1m) in tax synergies.
Last week, the US Treasury announced proposals to changes to the country's inversion rules, which essentially allowed US companies to switch their country of domicile for tax purposes when they merged with another company.
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The announcement led US-based Pfizer to scrap its plans to merge with Ireland's Allergan last week, which, at $160bn, would have been a record-breaking deal for the pharmaceuticals industry.
However, Shire has said that it does not believe that its planned $32bn merger with Baxalta will be caught by the change in rules.