Shortly after UNIX System V Release 4 was produced AT&T sold all its rights to UNIX to Novell. Dennis Ritchie, one of the creators of UNIX likened this to the Biblical story of Esau selling his birthright for some lentils [1]. Novell developed its own version, UNIXware, merging its Netware with UNIX System V Release 4. Novell tried to use this to battle against Windows NT, but their core markets suffered considerably.

In 1994, Novell decided to split the bundle of UNIX related assests and sell parts of them. The UNIX trademark and the certification rights were sold to the X/Open Consortium, which was an industry group to define a "UNIX Standard". Finally X/OPEN and OSF/1 (a competitor to the SVR4 standardisation) merged, creating the Open Group. Various standards by the Open Group now define what is and what isn't a "UNIX" operating system.

In 1995, the business of administration and support of the existing UNIX licenses plus rights to further develop the SystemV code base were transferred to the Santa Cruz Operation, (SCO). And Novell retained the core copyrights, veto rights over future licensing activities of SCO, and 95% of the licensing revenue.

In 2000, the Santa Cruz Operation sold its entire UNIX business and assets to Caldera Systems, which later on changed its name to The SCO Group. This new player then started a huge legal campaign against various users and vendors of Linux. The SCO Group has offered various legal theories over the course of several cases. Some of these allege that Linux contains copyrighted Unix code now owned by The SCO Group. Others allege trade-secret violations by IBM, or contract violations by former Santa Cruz customers who since converted to Linux. The most far reaching theory is that development work that IBM did for AIX is considered a derivative work and therefore also owned by SCO. If this is upheld it would affect all Unix licensees.

Under a program called SCOsource, the SCO Group is now offering licenses to all companies and individuals wishing to use operating systems with code based on UNIX System V Release 4 (and their own release, UNIX System V, Release 5).

However, Novell dispute the SCO group's claim to hold copyright on the UNIX source base. According to Novell, SCO (and hence the SCO group) are effectively franchise operators for Novell. The SCO Group disagree with this, and the dispute has resulted in the SCO v. Novell lawsuit.

The falseness of SCO/Caldera's allegations is partly cloaked by the fact that their complaint uses the term “Unix” in three different ways.

Among technical people and computer programmers, “Unix” describes a family of computer operating systems with common design elements, all patterned on (but not necessarily derivative works of) the ancestral Unix invented at Bell Labs in 1969. As SCO/Caldera observes in its complaint, Unix operating systems dominate serious computing, and have for more than twenty years. There have been hundreds of different Unixes in this sense, exhibiting variations analogous to dialects within a language. Fortunately, only a handful of the principal dialects are relevant to this lawsuit.

When we wish to be clear that this is the definition we are using, we will refer to “Unix-family” operating systems. Use of the term ‘Unix’ to describe any Unix-family operating system was common before SCO/Caldera's acquisition of the historical Unix codebase in 1995; AT&T's lawyers strove against it in vain as far back as the early 1980s. When we use the term ‘Unix’ without qualification elsewhere in this paper, this is the sense we intend.

The term “Unix” is sometimes also used (primarily by historians of computing) more strictly, to describe only those Unix-family operating systems which are derivative works of the original Bell Labs Unix. To avoid confusion, we shall call any operating system of this kind a “genetic Unix”.

Legally, the term “Unix” has been since 1994 a trademark of The Open Group[2], a technical standards organization, and describes any operating system (whether genetic-Unix or not) that has been verified to conform to the published Unix standard. We will refer to an operating system of this kind as a “trademark Unix”. The required attribution is “UNIX is a registered trademark of The Open Group”. [3] However, The Open Group's strict construction of the term “Unix” is more honored in the breach than the observance.

Neither SCO/Caldera nor old SCO has ever owned the UNIX trademark. IBM neither requested nor required SCO's permission to call their AIX offering a Unix. That decision lies not with the adventitious owner of the historical Bell Labs source code, but with The Open Group.

The Linux operating system is Unix-family and generally referred to as a Unix, but is neither a genetic Unix nor a trademark Unix. Linux was independently created by Linus Torvalds in 1991[4], and most versions have not been put through the rather expensive process required to verify conformance with The Open Group standards.

The name is spelled either as ‘Unix’ or ’UNIX’; its inventors prefer the former.

In paragraph 85 of the old complaint, SCO/Caldera claimed: “For example, Linux is currently capable of coordinating the simultaneous performance of 4 computer processors. UNIX, on the other hand, commonly links 16 processors and can successfully link up to 32 processors for simultaneous operation.”

Neither this claim or anything resembling it is in the amended complaint. This is because both halves are readily falsified from public information; Linux scales readily to 32 processors, and SCO's version of Unix does not.

32-processor SMP was already implemented under Linux in 2000.[47] 24-processor operation, three times the 8-processor limit of UnixWare, was demonstrated in 2000 on a Sun E10000[48].

Today, SGI is shipping Altix 3000 cluster computers that run Linux on over 64 processors[49].

In paragraph 84, SCO alleges: “To make Linux of necessary quality for use by enterprise customers, it needed to be re-designed and upgraded to accommodate complex multi-processor functionality that has taken UNIX nearly 20 years to achieve. This re-design is not technologically feasible or even possible at the enterprise level without (a) a high degree of design coordination, (b) access to expensive and sophisticated design and testing equipment; (c) access to UNIX code and development methods; (d) UNIX architectural experience; and (e) a very significant financial investment.”

Most of SCO/Caldera's complaint (as exemplified in paragraph 84) turns on (a) representing pre-IBM Linux as a primitive makeshift being slapped together by garage-band amateurs. Their implied narrative is that (b) only the corporate intervention of IBM made Linux a competitive product, and that (c) IBM's intervention was in turn only efficacious due to the ineffable superiority of the primal Bell Labs code base.

All three of these assertions are not merely false, they are profoundly disrespectful to the many, many developers worldwide who labored with sweat and brilliance to craft Linux into a world-class operating system for eight years before IBM came on the scene.

[...]

SCO's original claim read “access to UNIX code, methods and concepts”. They have backed away from this, quite possibly because they learned from the first version of this response that access to Unix “methods and concepts” is general in the community from which Linux development springs, and that said access is through codebases not subject to SCO's proprietary control or IP rights. For more than thirty years there has been a flourishing technical literature describing Unix operating system architecture and concepts. UNIX system internals and architecture are routinely taught in university computer science courses. Indeed, old SCO's and SCO/Caldera's own free publication of the Version 7 source code gave many programmers licit access to the ancestral Unix code, methods, and concepts.

To copy Unix source code would not be ethically wrong, but it is illegal; our work would fail to give users lawful freedom to cooperate if it were not done lawfully. To make sure we would not copy Unix source code or write anything similar, we told GNU contributors not even to look at Unix source code while developing code for GNU. We also suggested design approaches that differ from typical Unix design approaches, to ensure our code would not resemble Unix code. We did our best to avoid ever copying Unix code, despite our basic premise that to prohibit copying of software is morally wrong.

Another SCO tool of obfuscation is the term "intellectual property." This fashionable but foolish term carries an evident bias: that the right way to treat works, ideas, and names is as a kind of property. Less evident is the harm it does by inciting simplistic thinking: it lumps together diverse laws--copyright law, patent law, trademark law and others--which really have little in common. This leads people to suppose those laws are one single issue, the "intellectual property issue," and think about "it"--which means, to think at such a broad abstract level that the specific social issues raised by these various laws are not even visible. Any "opinion about intellectual property" is thus bound to be foolish. (See http://www.gnu.org/philosophy/words-to-avoid.html.)

In the hands of a propagandist for increased copyright or patent powers, the term is a way to prevent clear thinking. In the hands of someone making threats, the term is a tool for obfuscation: "We claim we can sue you over something, but we won't say what it is."

[...]

However, I can address the broader issue of such situations. In a community of over half a million developers, we can hardly expect that there will never be plagiarism. But it is no disaster; we discard that material and move on. If there is material in Linux that was contributed without legal authorization, the Linux developers will learn what it is and replace it. SCO cannot use its copyrights, or its contracts with specific parties, to suppress the lawful contributions of thousands of others. Linux itself is no longer essential: the GNU system became popular in conjunction with Linux, but today it also runs with two BSD kernels and the GNU kernel. Our community cannot be defeated by this.