Santa Cruz Operation, a company founded in 1979, which sold a major division and its namesake trademark in 2001, and has since renamed itself Tarantella. It was acquired by Sun Microsystems in 2005.
SCO Group, a company originally known as "Caldera Systems", which acquired several assets from Santa Cruz Operation in 2001: a UNIX licensing business, two divisions of the former Santa Cruz Operation, and the "SCO" trademark. Caldera later changed its name to "SCO Group".