1862 Dr Samule Duffield opened a drug store in 1866 in Detrioit, United States and began manufacturing; 1866 took C Parke into business became Duffield Parke and Co.; 1867 George S Davies taken into partnership; 1869 Duffield left the business and replaced by Jennings and became Parke, Jennings and Co.; 1871 Jennings left the business and it became Parke, Davis and Co.; 1874 became incorporated Parke, Davis and Co. Inc.; 1891 encorporated first overseas subsidary Parke Davies and Co. Ltd at 43 Holborn Viaduct, London; 1970 acquired as a whole by Walnut Lambert Inc