Governments around the world are making decisions regarding the procurement and public support of Free/Open Source Software (F/OSS). Government support of F/OSS has become a controversial topic in recent years, and at least two organizations—The Initiative for Software Choice and Sincere Choice—have formed to advocate different points of view.

One source of contention is the question of how governments should license software developed with public funds. There is widespread agreement that the introduction of publicly-funded software into the public domain is generally desirable, except in some special cases—situations where doing so might create a security risk, for example. The nature of the licenses that would govern this process, however, remains in dispute. Some argue that such software should be “copylefted,” that is, the source code of the product and all subsequent products that incorporate that source code should remain in the public domain. (The Gnu General Public License is one example of such a copyleft agreement.) Others, though, believe that public software should not be copylefted.

Philippe Aigrain proposes a framework to analyze this issue. He attempts to examine the various uses of public domain software. His framework aims to develop policies with two goals in mind: to provide the greatest use of public domain software, and to preserve the “commons” of the public domain.

Aigrain begins by pointing out that copyleft licenses may restrict some immediate uses of the software in question. (Others, including David Evans and Bernard Reddy, 2002, have made this same argument.) Public domain software can be improved and adapted to a variety of specific applications. A copyleft license discourages commercial firms from making these kinds of improvements. Under a copyleft license, all adaptations that are incorporated into the software’s source code must also be freely shared. This rule limits a firm’s ability to make profits, and it is conceivable that in some markets, such as small niches, firms might not be inclined to make improvements without a financial incentive. (Of course, a firm may decide to use proprietary software and copylefted software alongside each other. This is permissible as long as the source codes are separate, but such an arrangement often proves impractical.)

But Aigrain argues that there is more at stake here. He points out that most software products are components of more complex systems; for example, browser software used to view web sites inter-operates with the PC operating system, networking software, web server software, etc. When this is the case, a non-copyleft license permits firms to modify component interfaces, and the improved interfaces can then become proprietary. Microsoft’s famous “embrace and extend” strategy is the best example of this practice. With its Internet Explorer and ActiveX software, Microsoft adopted a public standard, added new features, and made their version—a new de facto standard—proprietary. Aigrain argues that with complex systems, non-copyleft licenses allow firms to appropriate standards that were previously in the public domain. This in turn limits the compatibility of public domain software, so that such software will lose much of its usefulness, undermining the value of the commons. Bruce Perens’s organization, Sincere Choice, expresses a similar concern with compatibility.

Aigrain argues that the risk of public-domain software being made proprietary outweighs the limitations on the development of improvements that a copyleft license tends to impose. “What we gain from copylefting,” he writes, “is a much greater degree of safety and sustainability of freedom, continued co-operation, and usability within the full range of activities for which [the software] was intended or later proved useful.” Admittedly, Aigrain does not present a complete argument for this position at this time, nor does he consider other means of preserving software compatibility. His aim in this short document is simply to provide a framework that may prove useful in more thorough policy analysis.

References
Evans, David S. and Bernard Reddy (2002), “Government Preferences for Promoting Open-Source Software: A Solution In Search Of a Problem,” NERA, pp. 74-7.