"GlaxoSmithKline plc (GSK) is a British multinational pharmaceutical company headquartered in London, England. Established in 2000 by a merger of Glaxo Wellcome and SmithKline Beecham, GSK was the world's sixth largest pharmaceutical company according to Forbes as of 2019, after Pfizer, Novartis, Roche, Sanofi, and Merck & Co.[n 1] GSK is the tenth largest pharmaceutical company and #296 on the 2019 Fortune 500, ranked behind other pharmaceutical companies including China Resources, Johnson & Johnson, Roche, Sinopharm, Pfizer, Novartis, Bayer, Merck, and Sanofi.
The company has a primary listing on the London Stock Exchange and is a constituent of the FTSE 100 Index. As of August 2016[update], it had a market capitalisation of £81 billion (about US$107 billion), the fourth largest on the London Stock Exchange. It has a secondary listing on the New York Stock Exchange." - (en.wikipedia.org 20.08.2021)
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