Microsoft consolidates Shared Source licenses

Microsoft said on Wednesday that it plans to consolidate the licensing terms for its Shared Source initiative under three license templates in an effort to simplify the program for developers.

The new licenses aim to reduce complexity and provide developers with more predictable terms for viewing Microsoft's code, according to Jason Matusow, director of the company's Shared Source Initiative. The initiative provides a select group of partners and customers with limited access to Microsoft's source code.

As with the broader open-source community, Microsoft has seen the number of licenses it uses increase. Microsoft currently has between 10 licenses and 12 licenses, Matusow said. It will not be completely retiring those as it moves toward the three-license structure, he said.

Matusow made the announcement in a session perhaps ironically titled "Sharing the Love" at the O'Reilly European Open Source Convention in Amsterdam. Microsoft is frequently assailed by open-source advocates for being overly protective of its source code.

The three new licenses are called the Microsoft Permissive License (Ms-PL), the Community License (Ms-CL) and the Reference License (Ms-RL). There will also be limited versions of the Permissive and Community licenses (Ms-LPL and Ms-LCL), Microsoft said. The company also released eight new Starter Kits for Visual Studio 2005, aimed at developers, under the new Permissive License.

As the open-source model becomes more commercialized it becomes more closed through licenses designed to create value, Matusow said, adding that that's not necessarily a bad thing.

"So a service contract that says you can't modify source code isn't about being against open source," Matusow said. "It's about saying 'Hey, I want to be able to deliver to you additional value, and if I send you a patch automatically and you change the source code, it may blow up your computer.'"

"On the other hand, companies like Microsoft need to learn that openness can create commercial value," he said.

The Permissive License is the least restrictive, allowing developers to view, modify and redistribute source code for either commercial or noncommercial purposes. Source code can be changed and then relicensed before sharing it with others, according to the company,.

The Community License will be based on the Mozilla Public License, a file-by-file arrangement on reciprocal terms. If developers take a piece of code, manipulate and then redistribute it, they only have to contribute back material contained in that file, Matusow said.

"To us, that is a more commercially reasonable approach to the mechanism of reciprocal licensing," Matusow said.

The most restrictive, the Reference License, will allow people to view code only and not to modify it. Explanations of the three licenses can be found at www.microsoft.com/sharedsource.

While some observers said Microsoft's announcement was broadly a positive one, what code the company will release under which license remains to be seen, they said.