In October 2010, Henri Termeer, the chairman and CEO of Genzyme, received a letter from the CEO of Sanofi-Aventis announcing its intention to commence a tender offer for Genzyme. Termeer thought the offer undervalued Genzyme, given the number of promising new drugs in the company’s pipeline and the success of its current drug portfolio. The case focuses on the strategic and financial considerations of a large corporate acquisition. To estimate Genzyme’s fundamental value, students must conduct a discounted cash flow and other valuation analyses. This case is designed to be part of a firm-valuation module within either a first-year MBA principles course or a second-year MBA elective; it can also be taught to executives who have M&A experience and can bring extra insights regarding the strategic fit and leadership issues.