Alongside the more typical summer fare, such as coverage of the best beach reading and the latest action movie blockbuster, this summer the media have been abuzz with seemingly daily reports on the latest so-called “inversion” transactions shifting a U.S.-based multinational corporation’s tax residence offshore. Recently announced transactions include the Medtronic acquisition of Irish-listed Covidien (which itself had previously inverted); Mylan’s acquisition of the Abbott Laboratories non-U.S. specialty and branded generics businesses for $5.3 billion in stock; and AbbVie’s $54 billion acquisition of Shire, a London-listed, Jersey incorporated, Irish tax resident corporation. Other transactions remain in the planning stages (Walgreens-Boots), and the largest such transaction proposed to date (Pfizer’s $100 billion-plus bid for UK-based AstraZeneca) has been shelved, at least temporarily, but remains very much in the media and political spotlight.

The pace at which inversion transactions are being announced shows no sign of slowing, and could even accelerate further if companies begin to make use of a variant which has been referred to as a “spinversion.” A spinversion would allow a larger conglomerate to spin-off one line of business to its shareholders using a separate entity that would then move offshore via a merger with a non-U.S. partner. Because this type of transaction would involve only one business line rather than the whole company, it could make inversion a possibility for companies for which a whole-company transaction would not be commercially viable (either because of sheer size or commercial constraints).