One of the quieter Microsoft policies that spurred newfound interest recently is Windows source-code licensing. Despite recent news reports, which at least partially blame the popularity of open-source OS Linux for this development, Microsoft tells me that it has been giving out the Windows source code for years. And although the company has indeed expanded the program in recent months, the move has absolutely nothing to do with Linux or any other open-source project. After speaking with Microsoft about this matter, I have to wonder: Why would a typical customer even want the Windows source code?

Steve Lipner, lead program manager for Microsoft's .NET Server Marketing Group explained the situation. "I'm not sure that everyone knows this, but Microsoft has licensed the Windows source code to large OEMs and academic and research institutions for a number of years, dating back to before the development of Windows NT. OEM licensing lets our partners adapt Windows to their platforms. Microsoft provides research and academic licensing for a variety of research and experimental purposes."

In the enterprise market that Microsoft is now chasing, corporations have been licensing OS source code for some time; companies such as IBM and Digital Equipment Corporation (DEC, now part of Compaq) have always given their largest customers OS source code. The reasons are practical: Large enterprises require OS source code to help them develop and tune applications for particular platforms. As Microsoft's OS products have moved into the higher-end enterprise markets, Microsoft has increasingly heard from customers that Windows source-code access would help them debug their own applications.

"In the interest of meeting this need," Lipner told me, "Microsoft started to explore its options about a year ago. Six months ago, a pilot program, which eventually grew to include about 12 customers in the United States, was begun to provide them with the Windows source code. Because \[the program\] was a success and customers found that access valuable, we are now rolling out the Enterprise Source Licensing Program in the United States. And we're planning to do pilot programs and rollouts in other geographies where we have major customers. The program itself will be open to 1000 major customers. We expect some customers will want it and others won't. When we're done, Microsoft will have hundreds of licensed customers in the United States."

Access to the Windows source code comes at a price, of course. Customers will have to sign extremely restrictive contracts, and they won't be able to modify the source code or create modified versions of Windows. The company says the reason is obvious: Microsoft doesn't want to see multiple versions of Windows out there. "We believe it's in our customer's best interests—and ours—to have a standard, stable platform," Lipner said.

One barrier to the source code is its size. The Enterprise Source Licensing Program provides select customers with the source code to all editions of Windows 2000, all Win2K service packs, and beta versions of Windows XP. Although Microsoft isn't talking, estimates place the amount of code in Win2K at 30 million lines, so the company is unlikely to ever open the source code up to a wider audience because only the largest companies have the facilities and technical staff to use the source code. "One of the biggest benefits is that for debugging, developers can set break points in the OS," Lipner said. Break points will help them determine where problems occur and get applications to market quicker.

One tidbit surprised me: Microsoft isn't setting up a formal bug-reporting process for these companies to use when they find bugs in the OS. Instead, bug reports will go through regular support channels. In fact, it was this decision that led to the publicity about the licensing program: When Microsoft had to alert its distributed support infrastructure to expect bug reports that might relate to Windows source code, the company realized that news of the source-code distribution would get out—and chose to proactively discuss the program with the press.

Finally, Lipner was quick to point out that Linux and other open-source software projects had absolutely nothing to do with the decision to expand Windows source-code licensing. "This program is an attempt to meet the needs of our customers, period," he said. "We're not doing this in reaction to Linux or anything else, any more than DEC's licensing of VMS \[a decade ago\] was in response to Linux. It's just something that our enterprise customers expect."

Although Microsoft isn't revealing the names of the corporations, financial institutions, and educational and research institutions that have licensed the Windows source code, it wouldn't be hard to guess who some of them are. But should Microsoft open up this code to all business customers? And shouldn't formal bug reporting be part of the program? Let me know what you think—and particularly whether having the Windows source code would help you build better applications that take advantage of this platform. Post your thoughts as a Reader Comment.