Merck & Co. is the third-largest pharmaceutical company in the world, according the ranking done by IMS. The company established its presence in the United States as a subsidiary of the original German company in 1891. The company operates in four operating segments namely Consumer Care, Animal Health, Pharmaceutical and Alliances. The largest segment of the company is the Pharmaceutical segment which accounted for 88% of revenues in 2012. Merck has a global presence but the majority of its revenues come from the US with Europe in second and Japan in third place. The Pharmaceutical segment produces products for many therapeutic sections which include cardiovascular, oncology HIV, respiratory etc.