>March 2001

Open Source Licensing

>by Nicholas Studt

The "Open Source" label has become so common that users rarely consider all the implications of the term. In fact, there is no universal definition of "Open Source." If you are working at home on a personal workstation with standard product distributions, you may never need to explore the subtle differences between Open Source variants. But if you write your own software, or if you dabble in the distribution of software, youýll need a clear understanding of the various license options.

In this article, I will discuss some of the prominent interpretations of the term "Open Source." For the terminology - minded, I will use the term "open source" when referring to free software and "Open Source" when referring to the abstract concept. There has been, and will be for the foreseeable future, debate over the correct use of each wording.

What Makes a License Open Source?

The first important task when evaluating Open Source licenses is to define them. Two of the standards organizations overseeing the open source world are the Open Source Initiative (OSI), a non-profit corporation that stemmed from the same roots as Debian, and the Free Software Foundation (FSF). Both OSI and FSF have established guidelines for what they consider "Open Source."

OSI lists nine guidelines(http://www.opensource.org/docs/definition.html) for determining whether a license can be declared Open Source. The OSI guidelines are slightly at odds with the Free Software Foundation's definition of what constitutes Open Source. The FSF takes a more holistic view of the license, specifying four freedoms that should be considered, along with the spirit of the license itself, when deciding whether a license is truly Open Source.