To get this ball rolling, Microsoft Thursday will publish on its Microsoft Developer Network Web site more than 30,000 pages of documentation for Windows client and server protocols that were previously available only under a trade-secret license through the Microsoft Work Group Server Protocol Program and the Microsoft Communication Protocol Program. Microsoft will publish protocol documentation for the other high-volume products in upcoming months, the company said.

Microsoft also is providing a covenant not to sue open-source developers for development or non-commercial distribution of implementations of these protocols -- a huge move for any Linux or open-source developers that may have feared litigation from Microsoft. The company said Thursday that developers will be able to use the documentation for free to develop products. However, companies that want to commercially distribute implementations of the protocols still must obtain a patent license from Microsoft, it said.

On the OOXML front, Microsoft promised Thursday to design new APIs for its Word, Excel and PowerPoint applications so developers can plug in additional document formats and enable users to set these formats as their default for saving documents. While there are add-on technologies that can translate between OOXML -- the default file format in Office 2007 -- and other file formats, Microsoft has not included the ability to set other file formats as default in the product suite.

Microsoft said Thursday it will use a new Open Source Interoperability Initiative to provide resources, facilities and events to the community, including labs, technical content and opportunities for ongoing cooperative development. Microsoft also is seeking an ongoing dialogue with customers, developers and open-source communities through an online Interoperability Forum. And Microsoft will launch a Document Interoperability Initiative to address the issue of data exchange between widely deployed formats, the company said.

The announcement reflects a change in the market in the past couple of decades, said Ray Ozzie, Microsoft's chief software architect, during a question and answer session at the press conference. "When Microsoft entered the game in the mid-1980s, people focused on using the PC. They tended to use a small number of programs," he said. Today, people use many more applications, and they expect data from one program to be available in other products, he said. The changes Microsoft is making adapt to that change in the market, he said.

Still, Ballmer cautioned that end-users shouldn't expect to see much change for some time. "Any opening up doesn't happen overnight," he said during the Q&A session. "I think it will be more like years than days" before end-users notice the effects of Thursday's announcements, he said.

Microsoft finds it hard to predict what kinds of new products might become available to users because of this change. "One thing the Net has shown is that sometimes, constraints around standards can be quite liberating to developers," said Ozzie. "Many times, new services pop out of nowhere once a standard is there and once interoperability principles are established because we can't think of the different potential uses of customer data and how to interface with products."

Ballmer said he doesn't expect the licensing changes to affect Microsoft's bottom line. "The amount of trade secrets licensing fees we forgo will be minimal," he said. The licensing changes are risky, he acknowledged, but the potential benefit for third parties to add value around Microsoft offerings balances the risk, he said.

While Thursday's announcements are related to Microsoft's legal problems in Europe, Ballmer argued that the changes were more driven by the market. "The announcement today is driven by what we're hearing from industry participants," he said.

Microsoft's Interoperability Executive Customer (IEC) Council will oversee the new principles and initiatives to help keep the company honest. The IEC is an advisory board established in 2006 and comprised mainly of chief information and technology officers from more than 40 companies and government institutions worldwide.

More information about the news can be found on Microsoft interoperability Web site.

This story was update on February 21, 2008