Software copyright is a complex issue, but an important one for the entire IT industry. The SCO–Linux disputes became one of the major milestones that helped define how software copyright and open-source software are treated.
In 2003, The SCO Group, which claimed to own the rights to UNIX, filed a lawsuit against IBM seeking $1 billion in damages over IBM’s commercial use of Linux. In the late 1990s and early 2000s, IBM openly stated that it was moving its businesses to Linux distributions wherever possible, while also investing heavily in the development of the open-source Linux kernel and Linux distributions. SCO claimed that it owned the rights to UNIX and that Linux contained code taken from UNIX, which it argued was a violation of the company’s copyrights. On that basis, SCO demanded $1 billion in damages.
The SCO Group obtained its UNIX rights after they passed through a series of companies. Bell Labs developed UNIX during the 1960s and 1970s and sold commercial licenses for it. For the next two decades, UNIX remained within AT&T, which owned Bell Labs. In 1993, Novell acquired the UNIX business from AT&T. The assets later passed to the Santa Cruz Operation and then to Caldera, which eventually renamed itself The SCO Group.
In 2003, SCO launched a public campaign to support its position, claiming that it owned the rights to UNIX and that parts of UNIX could be found in Linux. The company sent letters containing these claims to commercial organizations under the title “Letter to Linux Customers.” This campaign led to an unusual situation. Novell, which we mentioned earlier, received one of these letters and publicly stated that it had sold the Santa Cruz Operation only its UNIX business, not the copyrights to UNIX. In his letter, Jack Messman explained this and added that Novell had repeatedly pointed SCO to their contract, which concerned the sale of the UNIX business rather than the intellectual property rights to the operating system itself. Novell filed a lawsuit against SCO. Novell also stated directly that, as the company that owned the rights to UNIX, it had no claims against Linux or companies using Linux-based solutions.
This is only a small part of the story. There were several other related cases involving companies such as Red Hat, AutoZone, and others.
On August 10, 2007, a U.S. federal court ruled that the rights to UNIX did indeed belong to Novell, not SCO. The court also explicitly ruled that SCO had no right to pursue claims against Linux users. This decision is considered the main turning point in the various SCO–Linux disputes.
Nevertheless, litigation across several related cases continued for many more years. The SCO–Linux legal battles finally came to an end in 2021.
Sources
History of UNIX and Bell Labs
The Open Group — History of UNIX
Bell Labs — Dennis Ritchie: The Development of UNIX at Bell Labs
Sale of Novell’s UNIX Business to the Santa Cruz Operation
Novell, December 6, 1995 — Novell Completes Sale of UnixWare Business to The Santa Cruz Operation
SCO’s Lawsuit Against IBM
SCO and Novell Correspondence in 2003
August 10, 2007 Court Ruling
See also The Legal Battle That Changed OS History: AT&T Sues BSD in 1991 and How the Open Source Movement Began on February 3, 1998.