Open XML Incompatible With GPL

The royalty-free license under which Microsoft Corp. plans to make its upcoming Office Open XML Formats widely available is incompatible with the GNU General Public License and will prevent many open-source and free-software projects from using them, advocates say.

In addition, a leading patent official, Dan Ravicher, is questioning the validity and enforceability of Microsofts license and suggests that open-source and free-software developers need not comply with its conditions.

Microsoft, of Redmond, Wash., first made its Office 2003 XML Reference Schemas available in late 2003 under a royalty-free license. Then, earlier this month, Office officials said they not only plan to make the new XML file formats the default in Office 12, due next year, but also to make them available to anyone under that same license.

But Richard Stallman of Boston, president of the Free Software Foundation and the author of the GPL, dismissed any benefit to the open-source and free-software community from the move. The conditions imposed by the current license were "designed to prohibit all free software. It covers only code that implements, precisely, the Microsoft formats, which means that a program under this license does not permit modification," Stallman said.

"The freedom to modify the software for private use and the freedom to publish modified versions are two of the essential components in the definition of free software. If these freedoms are lacking, the program is not free software," he said.

Because the GPL is a "copyleft" license (a license that makes programs free and requires that all the modifications and extensions of the programs also be free), applying Microsofts restrictive license to GPL-covered programs would violate the GPL, Stallman said.

Jean Paoli, senior director of XML architecture for Microsoft, said, "Microsoft is committed to open XML file formats, and this move shows that we have moved away from binary content that no one can access."

However, Microsoft has included a provision that requires developers who use Office Open XML Formats to attribute the use of the file format in their code. This requirement could preclude any technology that uses the file formats from being used in Linux and other open-source technologies licensed under the GPL, Paoli said.

"The GPL may not allow code that is attributable to another company like Microsoft to be included. Our goal was to make it available to anyone who can use it without their having to ask Microsofts permission or return any modifications to us," Paoli said.

Patent specialists, such as Dan Ravicher, executive director of the Public Patent Foundation, in New York, suggest that those in the free-software and open-source development community need not comply with the license because of questions regarding Microsofts licensable rights.

"If [Microsoft has] rights and a license is needed, then the term in the license that requires attribution by the licensee of all of its downstream licenses is, in fact, not compatible with the GPL," Ravicher said. "However, we should not presume Microsoft has any valid rights here."

While Iyer Venkatesan, a product line manager for Sun Microsystems Inc.s client systems group, in Santa Clara, Calif., welcomed Microsofts decision to make its Office Open XML Formats available as a good first move, "Customers and partners may meet the new file formats with resistance or skepticism since Microsofts XML file format is not compliant with the OASIS [Organization for the Advancement of Structured Information Standards] OpenDocument file format," he said.

But the move would make it easier for Suns StarOffice desktop productivity suite to interoperate with Office going forward, Venkatesan said.