1960s, the prevailing business model around software was changing. A growing and evolving software industry was competing with the hardware manufacturer's bundled software products; rather than funding software development from hardware revenue, these new companies were selling software directly. Leased machines required software support while providing no revenue for software, and some customers who were able to better meet their own needs did not want the costs of software bundled with hardware product costs. In United States vs. IBM, filed January 17, 1969, the government charged that bundled software was anticompetitive. While some software was still being provided without monetary cost and license restriction, there was a growing amount of software that was only at a monetary cost with restricted licensing. In the 1970s and early 1980s, some parts of the software industry began using technical measures (such as distributing only binary copies of computer programs) to prevent computer users from being able to use reverse engineering techniques to study and customize software they had paid for. In 1980, the copyright law was extended to computer programs in the United States—previously, computer programs could be considered ideas, procedures, methods, systems, and processes, which are not copyrightable. Early on, closed-source software was uncommon until the mid-1970s to the 1980s, when IBM implemented in 1983 an "object code only" policy, no longer distributing source code. In 1983, Richard Stallman, longtime member of the hacker community at the MIT Artificial Intelligence Laboratory, announced the GNU project, saying that he had become frustrated with the effects of the change in culture of the computer industry and its users. Software development for the GNU operating system began in January 1984, and the Free Software Foundation (FSF) was founded in October 1985. An article outlining the project and its goals was published in March 1985 titled the GNU Manifesto. The manifesto included significant explanation of the GNU philosophy, Free Software Definition and "copyleft" ideas. The FSF takes the position that the fundamental issue Free software addresses is an ethical one—to ensure software users can exercise what it calls "The Four Essential Freedoms". The Linux kernel, created by Linus Torvalds, was released as freely modifiable source code in 1991. Initially, Linux was not released under either a Free software or an Open-source software license. However, with version 0.12 in February 1992, he relicensed the project under the GNU General Public License. FreeBSD and NetBSD (both derived from