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Patent Pledge for Open Source Developers

Microsoft irrevocably promises not to assert any Microsoft Necessary Claims against you as an open source software developer ("You") for making, using, importing, or distributing any implementation of a Covered Specification ("Covered Implementation"), subject to the following. This is a personal promise directly from Microsoft to You, and You acknowledge it is a condition of benefiting from it that no Microsoft rights are received from suppliers, distributors, or otherwise by any other person in connection with this promise. To benefit from this promise, You must be a natural or legal person participating in the creation of software code for an open source project. An "open source project" is a software development project the resulting source code of which is freely distributed, modified, or copied pursuant to an open source license. If You engage in the commercial distribution or importation of software derived from an open source project or if You make or use such software outside the scope of creating such software code, You do not benefit from this promise for such distribution or for these other activities.

To clarify, "Microsoft Necessary Claims" are those claims of Microsoft-owned or Microsoft-controlled patents that are necessary to implement the Covered Specification. "Covered Specifications" are listed below. Where a software development project has in all other respects the characteristics of an open source project, distribution among the participants of that project of source code developed by natural persons under an employment contract or by natural or legal persons under a contract to develop is not considered to be commercial distribution, and that software development project does not lose its character as an open source project merely because such distribution takes place among participants. Software is deemed to be commercially distributed within the meaning of this promise when the distributor derives revenues in connection with the distribution, such as from subscriptions, updates, or user-based connection fees or from services that are contractually required for a customer to obtain the current version and/or updates of the software product in question.

This promise is not an assurance either (i) that any of the Microsoft-issued patent claims cover a Covered Implementation or are enforceable or (ii) that a Covered Implementation would not infringe on patents or other intellectual property rights of any third party. No other rights except those expressly stated in this promise shall be deemed granted, waived, or received by implication, exhaustion, estoppel, or otherwise.

Covered Specifications (the promise applies individually to each of these specifications):

"Open Specifications" (as published at http://msdn.microsoft.com/en-us/library/dd208104(v=prot.10).aspx or its successor site) for the protocols implemented in the current and future versions of Windows Vista including the .NET Framework, Windows Server 2008, SQL Server 2008, Office 2007, Exchange 2007, and Office SharePoint Server 2007, that are used by any other Microsoft product to connect with these products.