OStatic

The difference between proprietary and open-source software all boils down to the license: If you release your program to the public with an open-source license, then it is open-source software. The same program, released under a restrictive proprietary license, is proprietary software.

As I have discussed in previous postings, the choice of a license is thus of great importance when releasing a program into the open-source world. BSD- and MIT-style licenses are fairly unrestrictive, allowing the software to be used, modified, and redistributed under almost any terms. The GNU Public License (GPL), by contrast, requires that any future, modified versions will also be licensed under the GPL. Once a program is released under the GPL, all future versions and modified versions become open source software.

So let's say that you write a program, and release it under the BSD license. You then discover, five years later, that your program has been incorporated into a wildly successful, closed-source commercial software product. While you might regret your decision, there's really very little that you can do: The BSD license allows your code to be used in whatever way other people see fit.

You might be upset that you haven't gained anything financially, and you might be even more upset that these people are ignoring their program's open-source origins. But you have no legal or financial recourse. To which BSD- and MIT-license fans say, "Good, because open-source software should be usable by anyone, for any purposes. And besides, the strength of the community makes it worthwhile for people to work with us, rather than trying to compete with us."

By contrast, if you release your program under the GPL, it can never be put into a closed-source program. The GPL stipulates that when someone distributes a binary, or executable, version of a GPL-licened program, that same person must also make available the source code to the program. So if Microsoft wants to include GNU Emacs in their next version of Word, they may do so -- but they are then obligated to provide every Word customer with the source code to Word. And yes, they must provide the source to all of Word, not just to the part that was derived by GNU Emacs.

But what happens if a company decides to use a GPL-licensed program in their proprietary product, and then refuses to provide the source code? You could sue them, of course, but open-source programmers typically don't have high-powered lawyers on their payroll. And while you might be able to find a lawyer willing to take the case on a pro-bono basis, they are unlikely to know much about the software industry, let alone the GPL.

It was for this purpose that the Software Freedom Law Center was established in 2005 -- to help open-source developers, and particularly those who use the GPL, to defend themselves when their software is used inappropriately by large organizations. And while they might not have a high profile, the SFLC announced earlier this week that they had won their fourth victory -- out of a total of four cases, giving them a 100% success rate so far.

Note that this doesn't mean that the SFLC has won in court; all four cases so far have been settled privately. And while the specifics of the settlements have not been made public, they have generally involved a financial payment, as well as the appointment of an "open source compliance officer" in each company. It is not clear from news reports whether the payment went to the SFLC, the original developer, or another party.

In this particular case, the SFLC had sued Verizon, which distributed a wireless router made by a comopany called Actiontec. Actiontec's system was apparently based in part on an open-source program called BusyBox, which has been used on Unix-type systems for years. BusyBox was released under the GPL, which means that Actiontec and Verizon were required to release any BusyBox-related source code they distributed. Neither Actiontec nor Verizon did this, which led to the lawsuit.

This is not the first time that a company has been contacted, or even sued, for violating the GPL. However, the GPL has rarely been tested in court, with the best-known (and perhaps only) actual court hearing being one between NuSphere/Progress and MySQL, back in 2002. Even then, the case was settled between the parties, so there isn't any precedent. But the day will undoubtedly come, and the SFLC is readying not just itself, but the many lawyers who pass through its doors.

• license
• gpl
• lawsuit