Microsoft is offering protection against patent claims for Office binary formats under its Open Specification Promise.

Microsoft on Friday said it has added Office binary formats to a list of technologies that are protected against patent-violation claims, answering criticism from some involved in the Office Open XML (OOXML) file-format standards process.

The OOXML format is being considered as an international standard by the ISO (International Organization for Standardization), but translation between the original Office binaries and OOXML is necessary for there to be seamless document exchange between older versions of Office and Office 2007. Corporate developers and makers of other office productivity products need access to the formats in order to write converters between Microsoft's format and the possible standard.

Microsoft has listed binary file format specifications for Word, Excel and PowerPoint -- that is, .doc, .xls and .ppt -- under the Open Specification Promise (OSP). These file formats are the defaults in pre-Office 2007 versions of Office; Office 2007 was the first version to use OOXML as its default file format.

Microsoft published the OSP in September 2006 as a promise that it would not take any patent-enforcement action against people who want access to the specs for technologies it has developed. Since then Microsoft has been periodically adding to the list of OSP-protected specs, which can be found on the company's Web site. In a press statement, Microsoft said that adding the Office binaries to the list is to "promote interoperability between the binaries and Open XML, and make Office Open XML accessible to an ever-wider group of users and developers."

The move came out of discussion in the ISO around OOXML, as national standards bodies requested more open access to the Office binaries, said Brian Jones, an Office program manager, in a posting on a company blog last month.

According to Jones, the specs for the binaries already had been available royalty-free via e-mail to anyone who requested them, as outlined in an article in Microsoft's Knowledge Base. But since the national bodies were concerned with the steps someone had to take to get access to the binary formats, Microsoft -- working with an Ecma International technical committee, Ecma TC45 -- decided to make it easier for people to get them, he said.

Microsoft has been working to fast-track OOXML through the ISO approval process through Ecma, another international standards body, since November 2005. Ecma approved OOXML in December 2006, but approval by the ISO has been more problematic. A final vote on ISO is expected in March after an ISO ballot resolution meeting for the OOXML format, scheduled for Feb. 25-29.

To help companies build connectors between the binaries and OOXML, Microsoft on Friday also went live with an open-source project on SourceForge to create software tools, guidance and show how a document written using the binary formats can be translated to the current ISO spec for OOXML, ISO/IEC DIS 29500. The resulting translators will be available under the open-source Berkeley Software Distribution (BSD) license, and members of the community are free to use the translators, submit bugs and feedback, or contribute to the project as they wish, Microsoft said.

Translators already exist between the Office binary formats and OOXML's rival file format, Open Document Format (ODF), which already is an approved ISO standard. For example, the Sun ODF Plug-in for Microsoft Office enables conversion between Microsoft Office documents to and from ODF.