The Pfizer-Allergan Tax Inversion

In November 2015, U.S.-based biopharmaceuticals company Pfizer [NYSE: PFE] and Ireland-based pharmaceutical company Allergan [NYSE: AGN] announced a $160 billion merger to move Pfizer’s domicile out of the United States to Ireland in the largest inversion deal ever. The announcement came just days after the U.S. Treasury Department laid out a set of restrictions on tax inversions; however, the deal was structured to avoid those restrictions.

According to the U.S. Department of the Treasury, “By undertaking an inversion transaction, companies move their tax residence overseas to avoid U.S. taxes without making significant changes in their business operations.” Two primary benefits provided by inversions were: (1) the removal of a company’s foreign operations and income from the U.S. taxing jurisdiction to achieve pure “territorial” tax treatment (in which income was taxed only in the country where it was earned); and (2) the reduction of U.S. taxes on income from U.S. operations through the use of various “earnings stripping strategies” (e.g., making payments of deductible interest or royalties from the U.S. entity to a new foreign parent). According to Reed College economist Kim Clausing, inversions and other income-shifting techniques reduced Treasury revenues by as much as $111 billion in 2012.

This case examines the tax and financial statement impacts of proposed tax inversions. It is designed to introduce tax inversions, and help students walk through an assessment of how a tax inversion might impact a company like Pfizer.