Modern Software Experience


Office File Format documentation

1.0 documentation

As you may recall, Microsoft already posted Office file format documentation, but that was far from complete. Today’s release extends and improves the available documentation, but does not complete the documentation set.
Preliminary versions of the documents announced today were available since April, so the announcement Microsoft makes today is really about the availability of the 1.0 version.


Microsoft has now documented "protocols built into Microsoft Office 2007, Microsoft Office SharePoint Server 2007 and Microsoft Exchange Server 2007" and posted "nearly 5,000 pages of new technical documentation for the Microsoft Office binary file formats for Word, Excel and PowerPoint (.doc, .xls, .xlsb and .ppt)".

The documentation is not still complete. Check my Office File Formats resource to get an idea of much documentation is still missing.


Microsoft has to publish a lot of documentation to be in full compliance with European court decisions and to stave off yet another investigation into its anti-competitive business practices, yet is again trying to spin the publication of these documents are part of their Interoperability Principles.

I am not sure whether they need to publish older Office formats for full compliance, but they probably do because newer formats are an evolution of the older ones - and Microsoft is wise to err on the safe side.


The release of this information now is not related to Bill Gates having left the company. Preparing these documents from what used to pass for internal documentation probably took months.

It has to do with the public pressure from governments, companies and individuals to documents the formats. Microsoft has learned to respect the European Court and is not happy that my Office File Formats resource collects links to third-party descriptions of their file formats.

protocol patents license

Microsoft claims various patents related to file formats and protocols. The Microsoft press release once notes that open source developers need not obtain a license for any patents covering the file formats, not for development or implementation, and not for non-commercial distribution either - so Microsoft still wants all commercial vendors, including open source vendors, to license their protocol.


The MSDN page does not provide all documents as a single package. It does not even offer direct download links for the individual documents. You can only download these by following a link to a page for the individual document, and clicking the direct download link there. However, you do not need to download them one by one. Once you are on any of these pages, you’ll find a link titled "Click here to download a zip file with all of the PDF files", to start the download of the current version of