Origins of open source licensing

Origins of open source licensing

Unix Operating system

  • The two models for software licensing (open source and proprietary) trace their origins from a common source: the Unix operating system.

  • Unix was developed by AT&T Bell Laboratories in the late 1960s and early 1970s and was the first general-purpose operating system.

  • At that time, AT&T’s market position was so dominant that the US Justice Department issued a consent decree barring AT&T from engaging in commercial activities outside the field of its telephone service, which was AT&T’s primary business.

  • Because of the consent decree, AT&T could not exploit Unix as a commercial product, so Bell Labs gave Unix away in source code form under terms that allowed its modification and redistribution.

  • This led to Unix’s widespread use and popularity among computer scientists in the 1970s and 1980s.

Proprietary licensing

  • After the US Justice Department lifted the consent decree in 1983, AT&T pivoted to commercialize Unix as a proprietary product and adopted more restrictive licensing terms that allowed Unix to be redistributed only in object code format.

  • Meanwhile, the 1980s saw the advent of microcomputers (PCs), which led to the standardization of software.

  • This standardization, in turn, encouraged companies to distribute their software in binary-only form because there was less need for users to investigate or troubleshoot source code.

  • And so proprietary licensing became the dominant model for licensing software.


  • Interest in open source licensing reemerged in the 1990s with the development of the Linux operating system.

  • Since the privatization of UNIX, the demand had swelled for an operating system that would be a free alternative to UNIX.

  • To be useful, operating system needed both an operating system kernel and the tools necessary to install, run and develop programs for it.

  • Linus Torvalds, a teenager in Finland, developed the first Linux kernel as a school project. Meanwhile, the GNU Project has been formed to develop those tools, and when those two parts were combined, a free alternative to UNIX was available.

  • The combined operating system, most commonly called Linux, was released under the GNU General Public License (GPL), a licensing model that was created by Richard Stallman of the GNU Project.

  • The GPL granted recipients unfettered rights to redistribute software with the condition that the source code could not be kept secret.

  • As Linux grew in popularity, with thousands of contributors and billions of users, the industry learned to follow and adopt GPL’s terms.

  • By the late 1990s, GPL and the open source licensing paradigm more broadly gained traction and industry-wide acceptance. In the 2010s, it has nearly eclipsed proprietary license in importance to the technology industry.”