Microsoft’s source program director, Jon Rosenberg, submitted both the Microsoft Permissive License (Ms-PL) and Microsoft Community License (Ms-CL) for consideration as OSI-approved licenses on Friday.
According to the terms of the approval process, submitters must identify which existing open source licenses are most similar to the license being submitted, as well as compatibilities and incompatibilities with existing licenses.
Rosenberg duly noted that the Ms-PL has similarities to terms in both the New BSD license and Apache 2.0 license. However, the new BSD license does not contain an explicit patent grant and only implicitly refers to trademark issues.
The Ms-CL, meanwhile, was described as most like the Mozilla Public License, with the differentiation that it is shorter and easier to understand. In particular, the Mozilla
Public License’s definitions of original code, covered code, and modifications can be difficult to apply in practice, given the many ways in which software can be distributed and linked together, Rosenberg wrote.
The MS-CL provides a clear objective test of whether or not derivative work constitutes a modification of the original code, he added.
As for in/compatibilities, Rosenberg noted that, like the Mozilla licenses, both Ms-PL and Ms-CL prohibit original code being re-licensed, or modifications being licensed, under a different license. A developer could not, therefore, take Ms-PL licensed code and re-license it under the GNU GPL, for example.
Additionally, Rosenberg noted that as long as the original license is maintained, there is no reason why Ms-PL and Ms-CL code should not be redistributed in combination with code under another license.
Both licenses have been in use since late 2005, when the Free Software Foundation Europe noted that they appeared to satisfy the four freedoms that define Free Software.
In order to be approved by the OSI the licenses will not only have to be fulfill the 10-point Open Source Definition but also be sufficiently different from existing OSI-approved licenses to avoid license proliferation.
While the approvals process is still in the initial stages, early feedback to both licenses on the OSI’s license discuss mailing list over the weekend was overwhelmingly positive.
