Microsoft licenses Office 2007 interface to third-party developers.

Microsoft has opened to the public the licensing documentation for the famous Office 2007 user interface. From now on, third-party manufacturers will be able to use some interface elements of the fresh Office, such as ribbons, in their products.

There are several limitations in the licensing program: you can’t get a free license for applications that directly compete with Word, Excel, PowerPoint, Outlook or Access. In open-source projects, you can use a license if the licenses are compatible. There are no restrictions on the platforms.


Interface license and FAQ
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MSDN section on interface licensing

Licensing the 2007 Microsoft Office User Interface, blog post by Jensen Harris, Office User Experience Software Manager

Preliminary version of Microsoft Office System UI Design Guidelines.pdf

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