By opening its .NET Framework libraries Microsoft is again responding to the leadership of the open source community, according to industry consultants and developers, but remaining on the back foot.

The software giant last week released its .NET framework library under a Microsoft Reference License, which means the code can be viewed but not modified or redistributed.

Open source consultant and developer Jeff Waugh believes the market is beginning to recognise Microsoft's behaviour when it's on the back foot. This move, he says, is just another sign.

"Instead of building great, market-building products, Microsoft is turning to legal threats, branch stacking (in the case of the standards battle around OOXML), and almost laughable attempts to embrace and extend its competitor's models (which we see with Google and Open Source)," he said.

"The sheen is gone, Vista is a wreck, and the market no longer believes that Microsoft is unstoppable."

Waugh said that the code won't even be useful for open source developers contributing to the Mono project, as they do not want their work contaminated by Intellectual Property (from Microsoft or elsewhere).

Waugh does not believe Microsoft's move in any way signifies a shift by the company towards open source methodologies.

"If the industry conversation wasn't dominated by open source, this code release would not rate a mention. They've made code available under similar terms in the past," he said.

"It is hard to see beyond the manipulation and cynicism in all of Microsoft's open source related moves to date."

Mono Project founder Miguel de Icaza is a little more hopeful, writing in his blog that even though the Microsoft Reference License for the code is not open source, it is an important step.

"Sun had done something similar with Java in the past and over time they moved towards opening more and more of it. I am still in hope that one day Microsoft will open pieces of this under more liberal licenses that would allow those pieces to be used for any purposes, including Mono."

Mono, an open source, Ecma compliant set of .NET compatible tools, including a C# compiler, continues to have the policy that any developer that has viewed .NET source code in any way is unable to contribute to the project.

Although Mono will not benefit from the .NET framework library, it does benefit from some of the code that Microsoft releases under the MS-PL license (Microsoft Permissive License, soon to be re-named the Microsoft Open License). Some of this code is redistributed in The Dynamic Language Runtime, IronPython, IronRuby and the ASP.NET AJAX Javascript client-side library.