Merck & Co., Inc. is an American multinational pharmaceutical company headquartered in Rahway, New Jersey. The company does business as Merck Sharp & Dohme or MSD outside the United States and Canada. It is one of the largest pharmaceutical companies in the world, generally ranking in the global top five by revenue. Merck & Co. was originally established as the American affiliate of Merck Group in 1891. Merck develops and produces medicines, vaccines, biologic therapies and animal health products. It has several blockbuster products, including cancer immunotherapy, anti-diabetic medications, and vaccines for HPV and chickenpox, each generating significant revenue as of 2020. The company is ranked 71st on the 2022 Fortune 500 and 87th on the 2022 Forbes Global 2000, both based on 2021 revenues. In 2023, the company’s seat in the Forbes Global 2000 was 73. Wikipedia