SCO, The SCO Group, The TSG Group, Caldera Systems, and Caldera International are the various names of an American software company that became known for acquiring the Santa Cruz Operation's Server Software and Services divisions, and UnixWare and OpenServer technologies, and then pursuing a series of legal battles known as the SCO-Linux controversies.The company was part of the Canopy Group, but became independent in March 2005, after the settlement of a lawsuit between the Noorda family and a chairman of the group, Ralph Yarro, also former CEO of the Canopy Group.