On January 22, 2007, Global pharmaceutical firm Pfizer Inc. anounced it was closing three research sites in the United States — Ann Arbor, MI, Esperion (also in Ann Arbor) and Kalamazoo, MI, displacing 2100 workers. The University of Michigan would eventually purchase the Ann Arbor Campus, creating a North Campus Research Complex and promising to hire 2-3000 employees over the next ten years.
Source : Nathan Bomey, “5th anniversary of Pfizer gut punch: Ann Arbor leaders recall ‘rallying cry'”, Ann Arbor News, January 22, 2012.