Microsoft defines GPLv3 licenses as including "GNU General Public License version 3, the GNU Affero General Public License version 3, the GNU Lesser General Public License version 3, and any equivalents to the foregoing," and also appears to ban further open source licenses, including any one that allows software to be redistributed for free. Excluded licenses include anything "disclosed or distributed in source code form; licensed for the purpose of making derivative works; or redistributable at no charge," Microsoft says.
Microsoft itself maintains two open source licenses: the Microsoft Public License and the Microsoft Reciprocal License.
Apple has also been criticized for its approach toward open source in the App Store for the iPhone and iPad. Last May, Free Software Foundation operations manager John Sullivan said Apple's developer license agreement is "incompatible" with GPLv3.
Microsoft's position toward open source software has evolved over the years, from CEO Steve Ballmer calling Linux a "cancer" to Microsoft official Jean Paoli saying "We love open source." Microsoft uses the Apache License for open source Outlook tools and funded the CodePlex foundation to host open source projects.
An open source database was ported to Windows Phone 7 last year by a third-party developer, but the database is not available on the Windows Phone Marketplace.
Microsoft has not yet responded to an inquiry from Network World today.
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