In 1834 John May, Joseph L. Pickett and Thomas S. Grimwade started a business for manufacturing chemicals for pharmaceuticals products known as Grimwade, May & Pickett at Battersea. Pickett died a year later and in 1839 when Grimwade left the partnership. May was joined by another chemist, William Garrard Baker. The new partnership was then called May and Baker. In December 1890, May & Baker was registered as a limited liability company, May & Baker Ltd. May & Baker Limited became the subsidiary of a French company, Poulenc Freres, in the early years of the 20th century. Following the company’s acquisition by the French company May & Baker moved to Dagenham in April 1934.