In the biggest deal of 2014 so far, Allergan has agreed to be acquired by Actavis for US$66 B after staving off the hostile advances of Valeant Pharmaceuticals International and activist investor Pershing Square.The deal will launch Actavis into the ranks of the top 10 pharmaceutical companies by sales, with the combined company forecast to generate sales in excess of US$23 B in 2015. It also offers the opportunity for significant tax savings given Actavis’ Irish tax domicile.