Open Software License

I wrote one of those licenses, the Open Software License. The third version of this license, OSL 3.0, was approved by Open Source Initiative in 2005. This article explains why it is a better license for software than the GPL. Consistent with open source principles, nothing in OSL 3.0 prevents anyone from selling or giving away OSL-licensed software or making a profitable business from it. Furthermore, once a licensee receives an authorized copy of OSL-licensed software, that person can make and distribute free copies and derivative works—but only under OSL 3.0, because OSL 3.0 is a reciprocal open source license. OSL 3.0 is a reciprocal (or "copyleft") license. It imposes a reciprocal source code disclosure obligation similar to (but narrower than) that of the GPL: Under OSL 3.0, Derivative Works of OSL 3.0-licensed Original Works must themselves be licensed under OSL 3.0, and therefore the Source Code of those Derivative Works must be disclosed. [The capitalized phrases throughout this article are defined terms in OSL 3.0.] The key reciprocity concept is stated in the underlined portion of § 1(c), which authorizes distribution "with the proviso that copies of Original Work or Derivative Works that You distribute or communicate shall be licensed under this Open Software License." This simple statement of reciprocity, coupled with the definition of Derivative Works in § 1(b), has important effects on the use and re-distribution of OSL-based derivative works. I will explain this more fully at IV below, but in overview, OSL 3.0 is less onerous in this respect than the GPL. Indeed, OSL 3.0 functions more like the LGPL than the GPL in that it doesn't attempt to force the disclosure of the source code of independently-written software. Licensees under OSL 3.0 can be more certain when they must disclose source code and when they may keep their source code secret. This ambiguity of the GPL is eliminated from OSL 3.0. By way of contrast, many early open source licenses, including GPL version 2, hardly mention patents. The scope of the patent grants and the patent defense provisions are uncertain in those licenses. GPLv3 went in the other direction and overreacted to certain patent issues involving Microsoft by reaching beyond simple defensive termination to impose other complex patent license conditions. Compare the patent provisions of OSL 3.0 to the patent provisions of the GPL variants; OSL 3.0 uses simpler and more precise language and reflects no political, anti-patent agenda. Further, it recognizes and respects patents and licenses them appropriately for open source purposes. The GPL has long confused lawyers about the scope of licensees' obligations to disclose source code. Debates rage to this day about how the GPL deals with static and dynamic linking and other esoteric techniques for making software work with other software. As a result, there isn't one GPL; there are GPL licenses with exceptions (such as for Linux, where dynamic linking to the Linux kernel is allowed), and even other versions such as the LGPL, which distinguishes "libraries" from other types of linked works. Even GPLv3 hasn't resolved that confusion; its authors see value in retaining the same fundamental bargain of GPLv2, namely that the source code of derivative works (defined broadly) must be published under the GPL. They did not want any clarification in GPLv3 that might narrow that copyleft obligation. The reciprocity and source code obligations of GPLv3 are still many paragraphs long, leading to continued confusion about the reach of its source code disclosure requirement. Then § 1(c) requires any copies of that Original Work and any Derivative Works that are distributed to be distributed under OSL 3.0 and, for those works, the Licensor promises to provide Source Code [§ 3]. In this way, the OSL 3.0 license remains with the work and all its subsequent versions, and that software always remains open source. That's reciprocity. Notice that the Sou