There are four main companies in the history of GSK: Burroughs Wellcome & Company, Glaxo Laboratories, Beecham, and SmithKline and French.
In 1880, Burroughs Wellcome & Company was founded. Wellcome Tropical Researches Laboratories was opened in 1902. McDougall & Robertson Inc. was bought by the Wellcome Company to be more active in animal health.
Glaxo was founded in Bunnythorpe, New Zealand. Originally a baby food manufacturer processing local milk into an early baby food by the same name, which was sold in the 1930s under the slogan Glaxo builds bonny babies. Glaxo became Glaxo Laboratories, and opened new units in London in 1935. Glaxo Laboratories bought two companies called Joseph Nathan and Allen & Hanburys in 1947 and 1958. After it bought Meyer Laboratories, it started to play an important role in US market. To be stronger force in the medicine market, Burroughs Wellcome and Glaxo merged in 1995. The new name of the company was GlaxoWellcome.
In 1830, John K. Smith opened its first pharmacy in Philadelphia. The company also wanted to spread all over the world to capture shares in various medicine markets, and to accomplish this they bought 7 more laboratories in Canada and US and changed its name to SmithKline Beckman.
In 1988, SmithKline Beckman bought its biggest competitor, International Clinical Laboratories, and enlarged by 50%. The next year, Beecham and SmithKline Beckman became one and changed the name of the company to SmithKline Beecham plc. The headquarters of the company were then moved to England.
The latest merge occurred in 2000 with GlaxoWellcome. Since 2000, the name of the company has been GlaxoSmithKline.