Daiichi Sankyo Co., Ltd. engages in the research, development, manufacture, and sale of pharmaceutical products. It operates through the following segments: Daiichi Sankyo Group and Ranbaxy Group. The Daiichi Sankyo Group segment comprises of Daiichi Sankyo Co., Ltd. and its subsidiaries. The Ranbaxy Group segment includes its core company, Ranbaxy Laboratories Ltd. Both group segments deal with business activities in prescription drugs and general pharmaceutical products. The company was founded on September 28, 2005 and is headquartered in Tokyo, Japan.