Бағдарламалық қамтамасыз ету патенттеріне қарсы және ашық лицензиялау туралы

Many people in the free software and open source community feel that software patents are harmful to software, and are particularly harmful to open source software. The OSL attempts to counteract that by creating a pool of software which a user can use if that user does not harm it by attacking it with a patent lawsuit.

Another goal of the OSL is to warrant provenance. blockquote |text=7) Warranty of Provenance and Disclaimer of Warranty. Licensor warrants that the copyright in and to the Original Work and the patent rights granted herein by Licensor are owned by the Licensor or are sublicensed to You under the terms of this License with the permission of the contributor(s) of those copyrights and patent rights. The verbs used in § 1(b) ["translate, adapt, alter, transform, modify, or arrange"] reflect the kinds of activities that we generally do to create derivative literary or other expressive works, and those things—not functional linking—create Derivative Works as defined in this license. As a result, linking an unchanged Original Work with another independently written work does not, absent more, create a Derivative Work subject to § 1(b); such an act is merely the incorporation of a copy of that Original Work into a collective work, authorized by § 1(a).

The OSL is intended to be similar to the LGPL. Note that the definition of Derivative Works in the OSL does not cover linking to OSL software/libraries so software that merely links to OSL software is not subject to the OSL license. The OSL is not compatible with the GPL. It has been claimed that the OSL is intended to be legally stronger than the GPL (with the main difference "making the software available for use over the Internet requires making the source code available" however, unlike the GPL, the OSL has never been tested in court and is not widely used.

If the FSF claim is true then the main difference between the GPL and OSL concerns possible restrictions on redistribution. Both licenses impose a kind of reciprocity condition requiring authors of extensions to the software to license those extensions with the respective license of the original work.

The patent action termination clause, described above, is a further significant difference between the OSL and GPL.

Derivative Works must be distributed under the same license. (§1c)
Covered works that are distributed must be accompanied by the source code, or access to it made available. (§3)
No restrictions on charging money for programs covered by the license, but source code must be included or made available for a reasonable fee. (§3)
Covered works that are distributed must include a verbatim copy of the license. (§16)
Distribution implies (but does not explicitly state) a royalty free license for any patents embodied in the software. (§2)

It is optional, though common for the copyright holder to add “or any later version” to the distribution terms in order to allow distribution under future versions of the license. This term is not directly mentioned in the OSL. However, it would seem to violate section 16, which requires a verbatim copy of the license.

NUnitLite up to 2.0 Alpha, a lightweight version of NUnit, NUnitLite is available under MIT / X / Expat Licence
CodeIgniter v3.0, an open source PHP framework (planned to use OSL, dropped because of GPL incompatibility for MIT License, may have used only for a short time for development release)