Pfizer-Allergan Acquisition

Pfizer announced that it would buy rival pharmaceutical company Allergan for about $160 billion. The new company will be based in Ireland, a tax inversion deal that will lower Pfizer's tax rate from 25 percent to 15 percent. The deal makes 2015 a record breaking year for mergers and acquisitions. For example, healthcare M&A deals have topped $600 billion, shattering the previous high of $362 billion in 2014. Energy and power M&A currently stands at $572 billion, while high technology M&A has reached $514 billion. And, worldwide, total M&A activity has reached $4.2 trillion, topping the previous high of $4.1 trillion set in 2007.